Brochure2010 en l

PD • Power Diagnostix Systems GmbH

Partial Discharge Measurement

High-Voltage Test Equipment

Instruments and Service

DiagnosisMonitoringQuality ControlResearch andDevelopment

Power Diagnostix ⋅ Vaalser Strasse 250 ⋅ 52074 Aachen ⋅ Tel +49 241 74927 ⋅ FAX +49 241 79521

PD •

Power Diagnostix Systems GmbH provides quality instruments and engineer-ing services for high-voltage diagnostic applications. Power Diagnostix has builta solid reputation since market introduction of our partial discharge detec-

tors in early 1993. Our ICMseries ofdigital partial discharge detectors isused for evaluation of electrical in-sulation by electric utilities, manufac-turers, and research institutes world-wide.In addition to digital partial dischargedetectors, Power Diagnostix pro-duces instruments for commissioningtests of GIS systems, automatedcontrol of high-voltage tests, fiberoptic connections for analog signal

transmission between instruments and sensors, and for other applications inhigh voltage. All of our instruments and specialized software products aredeveloped in Aachen, Germany.

Agents worldwide work in direct con-tact with us and our customers to findoptimized solutions for their applica-tions. The company's principal en-gineers are active in several scien-tific committees.

Company Profile

PD •

1

Power Diagnostix Systems GmbH

Ove

rvie

w

Mea

sure

men

t Sys

tem

s an

d In

stru

men

ts

Power Diagnostix Systems GmbH produces versatile, top-quality instruments forhigh-voltage diagnostic applications. Power Diagnostix ICMseries of partial dis-charge (PD) detectors is used worldwide for evaluation of electrical insulationused in electricity generation, transmission and distribution, in manufacturing, inresearch, and in industry. In addition to partial discharge detection equipment,Power Diagnostix produces instruments for fiber optic transmission, GIS faultlocation, tan δ measurements, and high-voltage test control.

Instruments

ICMsystem 5

The ICMsystem is a digital partial discharge detectionsystem. The instrument is completely controlled bysoftware using a GPIB, USB, TCP/IP, GSM Modem,fiber optic or direct serial link.

ICMsys8 7

The ICMsys8 is a true-parallel 8-channel acquisitionsystem, while offering all features of the single chan-nel ICMsystem. It is designed for acceptance testson large power transformers and other applicationrequiring parallel acquisition.

ICMcompact 9

The ICMcompact is a stand-alone partial discharge de-tector often used for quality assurance. Among otheroptions, the ICMcompact can be equipped with circuitsto perform partial discharge location in power cables.

SPECcompact 11

The SPECcompact is a narrow- and broad-band par-tial discharge detector with selectable center fre-quency. The unit offers as well spectrum analysis upto 10 MHz and a selectable bandwidth of 9 kHz or270 kHz.

ICMmonitor 13

The ICMmonitor is an instrument for continuous on-line monitoring of partial discharge activity in high volt-age equipment. The instrument tracks changes in keydischarge quantities for storage in trending diagramsand for triggering user-settable alarms. TCP/IP, Modem,fiber optic or direct serial links enable remote accessand full remote control.

PD •

Power Diagnostix Systems GmbHVaalser Strasse 25052074 AachenGermany

Email: [email protected] site: www.pdix.comTel: + 49 241 74927Fax: + 49 241 79521

Power Diagnostix 2010

2

HVcompact 25

The HVcompact is a high voltage meter with anauto-ranging oscilloscope display of the voltagewaveform. The unit displays Û, Û/√2, Urms, fre-quency, and crest factor.

The SPECmonitor is a partial discharge analyzercomprising a spectrum analyzer, an acoustic de-tector, and a conventional partial discharge moni-tor in one instrument.

The AIAcompact is a portable unit for acousticpartial discharge measurement on GIS, transform-ers, and cable accessories. Optionally, the unit canbe equipped with circuits for UHF measurements.

AIAcompact 17

SPECmonitor 15

The RIVmeter is an instrument for the measure-ment of 'Radio Influence Voltage' according toNEMA 107-1987 and other relevant standards.

The ICMflex instrument family, introduced in 2008,bases on the latest concept where the entire acqui-sition hardware is placed on high voltage potential.The instruments are fully remote controlled via highspeed Bluetooth or fiber optic communication.

The TDAcompact is a loss factor meter. The ca-pacitance Cx, the tanδ, and the voltage are derivedby digitally processing the currents of the test ca-pacitor and a reference capacitor.

TDAcompact 23

ICMflex 21

RIVmeter 19

PD •

3


Ove

rvie

w

Mea

sure

men

t Sys

tem

s an

d In

stru

men

ts

The STEPcompact allows running high voltage testsequences. The instrument controls via fiber opticcable the 'UP' and 'DOWN' contact of the motor drivenvoltage regulator (VARIAC). The instrument detectsincipient breakdown.

STEPcompact 27

The HVcontrol offers all features that are required tomanually control any high voltage test set. Currentlimits that trip the main circuit breaker can be set for Iprimand Isec.

HVcontrol 29

The FOsystem is a complete set of instruments for fi-ber optic transmission of analog signals from differentsensors (e. g. temperature, pressure, acoustic, voltage,current). The signal bandwidth covers DC up to 10 MHz.

FOsystem 31

The GISmonitor offers parallel, real-time acquisitionof UHF PD signals captured by any embedded or ex-ternal sensors permanently installed on gas-insulatedswitch gear (GIS). The system builds on compact8-channel sub-modules to allow flexible configuration.

GISmonitor 37

When a quadrupole and a coupling capacitor are usedtogether as the coupling device, high voltage is appliedboth to a test object and to the coupling capacitor in par-allel with the test object. A quadrupole (sometimes calleda measuring impedance) can then be placed in serieswith either the coupling capacitor or in series with thetest object. Preamplifiers serve to condition, filter, andamplify the PD signal to be measured.

Preamplifiers & Measuring Impedance 39

The ATTanalyzer supports commissioning of gas-in-sulated switchgear yards. Signals of up to 16 acous-tic sensors can be connected. Precise localization ofbreakdown within the GIS is provided by comparingthe travel-time of the breakdown sound to the varioussensors.

ATTanalyzer 35

PD •




4

We offer a variety of calibrators ranging from 1pC to50 nC. Due to their high bandwidth the calibratorsare suitable for impulse reflectometry on cable sys-tems and for GIS testing. New charge calibratorsare shipped with the DKD calibration certificate toensure the traceability to international standards.

Calibrators (CAL) 49

Typical PD Pattern 63

With the PD pattern (ϕ-q-n pattern), each acquiredimpulse is sorted and counted with respect to itsphase angle and acquired amplitude. The patterncontains information of various properties of thedefect causing the discharge.

Coupling capacitors with built-in quadrupoles areused to capture the PD signals and to synchronizethe measurement to the test frequency. Addition-ally, rugged coupling capacitors are used for per-manent installation for monitoring purpose.

Coupling Devices & Filters 43

We offer various sensors for temporary or perma-nent installation with gas-insulated switchgear (GIS),cable accessories, and power transformer. For ex-isting measurement taps of transformer bushings aseries of bushing adapters is offered.

Sensors and Miscellaneous 45

We offer on- and off-line PD analysis on rotatingmachines, transformers, cables, etc. Instruments canbe provided temporarily on a rental base. Further-more, an on-site DKD-calibration of HVAC measure-ment systems up to 100 kV can be performed.

Services 61

Using the range of instruments with the different ap-plications, such as rotating machines, power trans-formers, cable systems, or GIS and GIL, requiresconsidering the special conditions of each field.

Applications 51

PD •

5


Inst

rum

ents

The ICMsystem is part of the Power Diagnostix ICMseries of digital partial dis-charge detectors. The ICMsystem is a powerful, versatile instrument for evaluat-ing the condition of medium and high voltage insulation. The ICMsystem is us-able over a range of frequencies of applied voltage, including power systemfrequency (50/60 Hz) and VLF (0.1 Hz).

Partial discharge (PD) measurementsare a proven method for effective, non-destructive evaluation of electrical insu-lation. The Power Diagnostix ICMsystemprovides high-resolution digital PD pat-terns for characterization of defects inhigh voltage insulation systems.

VersatilityThe key to the versatil ity of theICMsystem is its modular design. TheICMsystem can be matched up with avariety of special accessories that adaptit to virtually any high-voltage testing en-vironment. A wide range of externalpreamplifiers provides control of the fre-quency range in which PD activity is de-tected, from 40 kHz up to 2 GHz.

Phase-Resolved PD Pattern

ICMsystemIC

Msy

stem

- D

igita

l Par

tial D

isch

arge

Det

ecto

r

The key to the versatility ofthe ICMsystem is its

modular design.

Assorted coupling devices, includingquadrupoles, coupling capacitors, andcurrent transformers, are available tosense the PD signal in the object un-der test. Like the other instruments in

the ICMseries, the ICMsystem provideseffective noise gating that blocksphase-stable noise as well as noise in-dependent of the applied voltage cycle,allowing the ICMsystem to be used innoisy environments without losing sig-nificant PD data. Appropriate selectionof a preamplifier can assist further inachieving a high signal-to-noise ratio.

PC SoftwareThe operating parameters of theICMsystem are fully computer con-trolled, making it simple to use withstandard Power Diagnostix software.The actual recording of PD patterns isindependent of the PC, so the perfor-mance of the ICMsystem is unaffectedby speed limitations of the PC or com-munications.

PD •




6

Giving users complete access to detailed control parameters and the abilityto download and analyze PD patterns on a PC makes the ICMsystem theideal instrument for advanced analysis of phase-resolved partial dischargepatterns, whether in research, utility, or industrial applications.

The ICMsystem’s PC software in-cludes convenient options for in-depthanalysis and printing of stored PD pat-terns.

Special Applications and OptionsFor applications such as DC testingor stepped high-voltage testing, theICMsystem allows recording PD ac-tivity versus time (sequentially) in-stead of versus phase angle. Optionssuch as a multiplexer module, fiberoptic bus, and built-in modem furtherextend the capabilities of the ICMsys-tem. The multiplexer module, workingwith ICMmux software, allows easyselection among eight channels forPD measurement. The fiber optic busprovides enhanced protection in haz-ardous measurement conditions and

can link widely separated compo-nents of a test setup. The modem op-tion permits remote access to dataand control of the ICMsystem. Thefull command set of the ICMsystemis provided with the device also, sousers may create custom programsto control the ICMsystem for highlyspecialized applications or for inte-gration into an overall high-voltagetest control program.

Options:• Multiplexer• Built-in spectrum analyzer• RIV measurement• Cable fault location• Acoustic PD location

PD •

7


Inst

rum

ents

ICMsys8IC

Msy

s8 -

True

Eig

ht-C

hann

el D

igita

l PD

Det

ecto

r The ICMsys8 is specifically designed to meet the requirements of partial dis-charge acceptance tests on large power transformers. The instrument builds onthe acquisition core of the standard ICMsystem. However, by introducing an indi-vidual amplifier plug-in for each channel, true parallel acquisition of the dischargemagnitude of eight channels is achieved. The instrument can be equipped withoptional features like RIV or acoustic PD measurement.

Using the eight-channel ICMsys8 greatlysimplifies partial discharge acceptancetests on large power transformers. Withthe true parallel acquisition of the par-tial discharge activity on eight channels,the overall testing period is substantiallyshortened.

Independent ChannelsFor each of the eight partial dischargemeasurement channels an independentquadrupole, pre-amplifier, and amplifierplug-in is provided. Internally, the sys-tem controller processes the dischargereadings acquired for each channel ina true bipolar peak amplitude acquisi-tion. Optionally, the PD readings can beweighted according to IEC60270-2000.Besides the eight partial dischargechannels, the instrument offers eight

independent channels for the measure-ment and sampling of the AC voltagesignal provided by the quadrupole.

Pattern AcquisitionIn addition to the parallel acquisition ofthe PD activity for the meter and strip-chart displays, the pattern acquisitioncore known from the standardICMsystem offers the defect identifica-tion capabilities of the phase-resolvedpartial discharge analysis. The influ-ence of power frequency harmonics onthe PD pattern, often found with powertransformers, can be clearly identified,as the waveform of the AC voltage isavailable for each channel.

SoftwareThe control software to run the eight-channel ICMsys8 offers manual andautomatic modes for the acceptance test.

Voltage

1.1

1.5

1.7

5min 60min

* : Manual Triggered^ : Auto Triggered

****

****

*

* *

*

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

*

Time

Typical test sequence for HV transformer

True eight-channel partialdischarge acquisition

PD •




8

ICMsys8 installed in a control room

The ICMsys8 for power transformer acceptance testing is the first commerciallyavailable partial discharge detector with true parallel acquisition on eight chan-nels. The ICMsys8 and its software greatly simplify the testing procedures and,thus, reduce the time the transformer needs to stay in the acceptance test lab.

CC

GND U

PD

CIL4M/V5

RPA1C1 C2

BushingTap

SYNC AMP IN

100 pC

HV off

Reporting is simplified with MS Wordand plain text output formats. The re-ports are based on user-selectabletemplates.In acceptance test mode, the softwareshows eight meter displays, each in-dicating PD level, voltage, and fre-quency of the specific channel. Withthe center display, the automaticallyor manually triggered values are pre-sented in list mode or as a strip-chart.Further, during calibration, the cross-coupling matrix between the channelsis built up, which eventually can helplocating the source of PD activity. Ad-ditionally, the ICMsys8 software pro-vides the user with all the featuresknown from the standard ICMsystem,

such as multi-channel consecutivepattern acquisition, movie-like replay,or statistical evaluation, for instance.

PD •

9


Inst

rum

ents

ICM

com

pact

- D

igita

l Par

tial D

isch

arge

Det

ecto

r

The ICMcompact is part of the Power Diagnostix ICMseries of digital partial dis-charge detectors. The ICMcompact is a compact, stand-alone instrument forevaluating the condition of medium and high voltage insulation. It is often usedin quality assurance and quality control tests in manufacturing.

Stand-Alone InstrumentPartial discharge (PD) measurementsare a proven method for effective, non-destructive evaluation of electrical in-sulation. The Power Diagnostix ICM-compact provides a simple push-buttoninterface and on-screen menus in anembedded LCD panel. The LCD displaymodes include a simple PD chargemeter with adjustable “needle” sensitiv-ity, monochrome phase-resolved PDpatterns for characterization of defects,and a scope-like display showingphase-summed charge pulses superim-posed with the applied voltage wave.

Phase-resolved PD pattern

ICMcompact

Although the ICMcompact is an autono-mous unit, it can be connected to acomputer installed with PowerDiagnostix software to capturescreenshots or to implement remotecontrol of the unit.

ApplicationsInstantly displaying information in an in-tuitive interface, the ICMcompact is agood choice for applications such asquality control tests in manufacture ofelectrical products, and for quality as-surance of industrial and utility equip-ment from capacitors and bushings togas-insulated switchgear and others. Awide range of accessories adapts theICMcompact to specific testing applica-tions and noise conditions.The ICMcompact equipped with an op-tional DSO board can be used to lo-cate partial discharge defects in powercable. Using time domain reflectometry,in which the PD and its “echoes” travelthe length of the cable under test, theICMcompact provides the proportionaldistance of the PD fault along the cable.

PD •




10

The easy portability, simple operation, and flexibility of the Power DiagnostixICMcompact make it a good choice for routine PD testing in a variety of utilityand industrial applications.

The ICMcompact offers convenienton-site testing of equipment such ascable accessories or sensors installedwith gas insulated switchgear, for in-stance. Generally, this unit can beused with the full range of theICMseries preamplifiers, covering theIEC60270 standard and ultrasonicfrequencies up to the UHF range(20 kHz - 2 GHz).

To adapt the basic ICMcompact unitto suit special measurement require-ments, it can be equipped with vari-ous options:

• Voltage measurement. Adds theHVM oscilloscopic display showingthe waveform of the high voltage andcalculates Û, Û/√2, Urms, etc.• Cable PD location. An additionalDSO board samples the PD signal at100 Msample.

• Analog gating to cancel external distur-bance. This option offers sensitive mea-surements even in noisy environments.• TTL-Gating. Unconditioned gatingon an external TTL signal to combinethe ICMcompact with IGBT drivenresonant high voltage test sets.• UHF measurements on GIS. Comeswith a logarithmic display for the UHFpreamplifier RPA6C• MUX4. Four-channel multiplexer fortesting three-phase equipment, suchas power transformers. For eachchannel the unit maintains an indi-vidual setup and calibration.• MUX12. With this option a remote12-channel switching box offers cost-efficient acceptance testing on largepower transformers.• AUX8. For long-term testing up toeight additional parameters can becaptured as 0(4)-20 mA or 0-10 V sig-nals.

PD •

11


Inst

rum

ents

SPECcompact

The SPECcompact comprises a spectrum analyzer, a partial discharge (PD) de-tector and an RIV meter in one instrument. This combination enables PD mea-surements even with a large background noise e.g. in non-shielded test areas.

Measuring partial dischargewithin noisy environment

Observing the frequency spectrum of aharshly disturbed PD signal allows se-lecting frequency bands with less dis-turbances. Using this selected fre-quency for a PD acquisition gives alargely improved signal-to-noise ratioresulting in a clear pattern acquisition.The combination of spectrum analyzerand PD detector within one instrumentopens a broad field of new possibilitieswhen analyzing isolation defects evenwith large noise.

There are three main display modesand a high voltage meter (HVM) as op-tional function:

SPEC ModeThe SPEC mode shows the frequencyspectrum of the input signal with a se-lectable span of up to 10 MHz. Threespectrum traces of the current inputchannel can be stored, compared andanalyzed. A variable cursor serves toset the center frequency for the PDpattern acquisition.

The SPECcompact comes with one,three or eleven channels. A multiplexerallows to directly select the input signal.SP

ECco

mpa

ct -

PD D

etec

tor w

ith S

elec

tabl

e Fr

eque

ncy

Spectrum scan displayFrequency spectrum

SCOPE ModeThe SCOPE mode displays the PD pat-tern versus phase as known from theICMseries. The SYNC f requencyranges from 10 to 500 Hz. The PD ac-tivity can be shown as vertical bars oras dots to get a so called PD pattern.

PD •




12

tion or power frequency harmonics,for instance, are clearly identified withthis display. The screen is automati-cally synchronized with the measuredvoltage and the amplitude deflectionis controlled by an auto-range function.

SCOPE mode (NORM) METER mode (RIV & HVM)

HVM mode

The SPECcompact comprises a spectrum analyzer, a partial discharge (PD)detector and an RIV meter in one instrument. This combination enables PDmeasurements even with a large background noise e.g. in non-shielded testareas.

METER ModeThe METER mode can be chosen tovisualize the PD activity like older ana-log meters. Three modes are availablefor the charge value in ‘pC’ (FAST,NORM, IEC270) and one for the volt-age value in ‘µV’ (RIV).

HVM ModeThe high voltage meter (HVM) is anoptional function to observe the mea-sured voltage waveform. The HVMshows the voltage supplied at theSYNC input. The input voltage issampled in high resolution and onecycle is displayed as an oscilloscopictrace. Any distortion of the high volt-age due to transformer core satura-

SCOPE mode (HOLD)

Accessories for RIV measurement

PD •

13


Inst

rum

ents

ICMmonitor

The ICMmonitor is part of the Power Diagnostix ICMseries of digital partial dis-charge detectors. The ICMmonitor is a compact, stand-alone instrument for evalu-ating the condition of medium and high voltage insulation. A built-in four-, or eight-channel multiplexer offers scanning of three-phase systems or multiple sensors. Itis used principally for permanent, continuous on-line monitoring of rotating ma-chines, cable systems, power transformers, and gas-insulated switch gear (GIS).

Partial discharge (PD) measurementsare a proven method for effective, non-destructive evaluation of electrical insu-lation, preventing expensive unplannedoutages by detecting insulation problemsbefore they can cause breakdowns. ThePower Diagnostix ICMmonitor is a non-invasive digital PD detector for perma-nent installation and continuous moni-toring of medium and high-voltage in-sulation.

play for characterization of defects, ascope-like display showing phase-summed charge pulses superimposedwith the applied voltage wave, a timetrending display, and a monitoring dis-play showing bar graphs of two key par-tial discharge quantities (Qp and NQS).Qp is the apparent charge value of thePD activity, and NQS is the absolutedischarge current obtained by integrat-ing the discharge values (summing upthe total charge moved and dividing bythe time interval, Q/t = [As]/[s]).

Noise RejectionThe ICMmonitor features various noisehandling techniques. The noise gatingmodule can be connected to an antennaor a current transformer to sense andremove noise without losing significantPD data. Another method available issimple windowing, that supressesphase-stable noise for certain portionsof each applied high voltage wave. Ad-ditionally, appropriate choice of the ex-ternal preamplifier can limit noise by de-tecting PD in a frequency band outsidethe range of the noise.

Monochrome PD pattern display

ICM

mon

itor -

Dig

ital P

artia

l Dis

char

ge D

etec

tor

Embedded DisplayThe ICMmonitor has a simple push-but-ton interface to navigate on-screenmenus in an embedded LCD panel. TheLCD display modes include a mono-chrome phase-resolved PD pattern dis-

PD •




14

The multifunctional ICMmonitor, with its embedded display, convenient trend-ing, and settable alarms, is an ideal solution for continuous on-line monitor-ing of rotating machines and other electric devices in industrial and utilityapplications.

Alarms and TrendingUsers can set alarm levels of NQS orQp that will trigger when those valuesare exceeded. A triggered alarm willsound, appear on the LCD display, andactivate an output on the ICMmonitorthat can be used to drive a relay forinterfacing with a local alarm system.The ICMmonitor also collects and dis-plays PD data over a specified time in-terval for easy trending and observa-tions of changes in the Qp and NQSlevels in the monitored system. Option-ally, up to eight DC signals such astemperature or load can be added tothis trending.TelemonitoringAlthough the ICMmonitor is an autono-mous unit, it can be connected todownload data or to implement remotecontrol of the unit. With its built-in TCP/IP interface or analog modem, theICMmonitor can be controlled and ob-

served remotely over a telephone orInternet connection anywhere in theworld. Optionally, if a monitored sys-tem exceeds an alarm level set by theuser, the ICMmonitor can place a callto a user-selected number. TheICMmonitor software automaticallymaintains the trending information aswell as the phase-resolved pattern ofa multitude of ICMmonitor units.

Portable ICMmonitor with modem

PD •

15


Inst

rum

ents

The SPECmonitor is a partial discharge (PD) measurement device comprising aspectrum analyzer, an acoustic detector, and a conventional PD monitor in oneinstrument. This combination enables PD measurements even with high levelsof background noise e.g. on power transformer within substations or power plants.

Observing the frequency spectrum of a harshly disturbed PD signal allows toselect frequency bands with less disturbances. Using this center frequency for aPD acquisition, gives a largely improved signal-to-noise ratio resulting in a clearpattern acquisition. The combination of spectrum analyzer and PD detector withinone instrument greatly expands the measurement possibilities when analyzingthe insulation systems in a noisy environment.

SPEC

mon

itor -

PD

Mon

itor w

ith S

elec

tabl

e Fr

eque

ncy

In the standard version, theSPECmonitor comes with an eight or fourchannel multiplexer to directly select theinput signal. The instrument provides fivedifferent display modes and several in-terfaces like e.g. TCP/IP or modem forremote control and diagnosis.SPEC Mode

SPEC ModeThe SPEC mode shows the frequencyspectrum of the input signal up to10MHz. Three traces for the current in-put channel allow storing, comparingand processing of this spectrum. Thebandwidth of the demodulated signalcan be set to 9 kHz or 270 kHz,respectively.SCOPE Mode

SCOPE ModeThe SCOPE mode displays the PD pat-tern versus phase as known from theICMseries. Hereby, the selected cen-ter frequency and bandwidth of theSPEC mode is used, in order to disre-gard frequency ranges occupied withdisturbances. The SCOPE mode offersviewing an oscilloscopic display (below)as well as a pattern display.

SPECmonitor

Measuring partial dischargewithin noisy environment

Scope display

PD •




16

Monitoring display

Spectrum display

Trending display

SPECmonitor in a full 19'' rack

Combining a spectrum analyzer and the multifunctional ICMmonitor greatlyexpands the measurement possibilities of the SPECmonitor. This combina-tion allows PD monitoring even with a large background noise and with dif-ferent sensors connected.

Acoustic sensor withmagnetic holder

Bushing adapterand coupling unit

MON ModeThe monitoring display allows to setalarm levels of NQS or Qp that will trig-ger when those values are exceeded.

TIME ModeAdditionally, the SPECmonitor collectsand displays PD data over a specifiedtime interval for easy trending and ob-servations of changes in the Qp andNQS levels of the monitored system.

SoftwareBesides this autonomous functions,the instrument can be connected to acomputer via serial interface, modem,or TCP/IP. A special software allowsthe remote control of the instrumentand the download of the stored data.An autoscan function takes the trend-ing information as well as the phase-resolved pattern of one or multipleunits.

AccessoriesIt is possible to connect acoustic sen-sors (AS), UHF sensors, or the stan-dard coupling unit from the bushingtest tap to the SPECmonitor.

SPECmonitor software

Different preamplifiers like RPA1F,RPA1L or RPA6C can be used incase of weak signals or to drive longcable lengths.

AS

PD

UHF RPA6C

AMP

SPEC

A

LCD

PC

40-800kHz

10KHz-10MHzBW: 9 / 270kHz

SPECmonitor

preamplifiersensor 8x MUX

µCD

AD

optional

RPA1L

optional

RPA1F

IPUoptional

Principle connection diagram

PD •

17


Inst

rum

ents

AIAcompact

The AIAcompact is a portable unit for in-service acoustic partial discharge mea-surements on gas-insulated switchgear (GIS), transformers, and cable accesso-ries. The instrument adapts to a variety of piezo-electric acoustic sensors and issupplied with a versatile sensor fixture. Additionally, the AIAcompact allows par-tial discharge measurements on embedded or external UHF sensors.

AIAc

ompa

ct -

Acou

stic

Insu

latio

n An

alyz

er

Acoustic partial discharge measure-ments can be easily applied on gas-in-sulated switchgear and other high volt-age equipment without the need of in-terrupting the operation. Such in-servicemeasurements help to identify internalimperfections of the insulation system,which may lead to breakdown and sys-tem failure in the future.

Acoustic partial discharge measure-ments rely on the close acoustic con-tact of the area producing the dischargeto the point of access, where the sen-sor is placed. Most of the partial dis-charge activity in GIS offer such a goodcontact and, hence, can be detected ata good sensitivity.Therefore, discharges from sharp pointsor cones as well as discharge activity

from delaminations can be identified ata sensitivity, which is mostly compa-rable to the conventional electrical de-tection according to the IEC60270.For some defect types, such as the so-called hopping or bouncing particles,the acoustic detection is by far supe-rior to the electrical detection. Such freeparticles can cause flashover and se-vere breakdown especially in the initialphase after erection or maintenance ofgas-insulated switchgear.Based on the proven hardware core ofthe ICMcompact, the AIAcompact offersautomatic detection of the sensor orpreamplifier used. Normally, the instru-ment is operated with acoustic sensorswith remote supplied embedded pre-amplifiers directly connected to the sig-nal input. Alternatively, the RPA1D,known from the ICMsystem, can be in-serted close to the sensor to boost thesignal, which can be mandatory, in caselonger signal cables are used or in caseof low-level measurements.

Easy-to-apply substationcondition assessment

PD •




18

Offering easy-to-use acoustic partial discharge analysis of gas-insulatedswitchgear (GIS) and other high voltage equipment plus the optional analysis onembedded or external UHF sensors makes the AIAcompact the ideal solutionfor convenient in-service substation condition assessment.

UHF measurements on embed-ded or external sensors are pos-sible with the use of the RPA6C,a logarithmic preamplifier, whichcovers 300 MHz - 2 GHz. Aswith the other preamplifiers, theAIAcompact automatically detects theRPA6C and changes into the logarith-mic display for the UHF detection.Generally, the instrument offers threemain display modes, which are se-lected using dedicated control but-tons: Scope, Meter, and Time.

ScopeIn Scope mode, the AIAcompactshows the phase-resolved partial dis-charge signal or pattern as the stan-dard ICMcompact. Here, the 'Freeze'function allows keeping a capturedphase-resolved partial discharge pat-tern for further evaluation or for tak-ing screenshots.

MeterThe Meter mode offers four bar graphdisplays showing derived quantitiesof the captured activity. The graphsdisplay the RMS and the peak PDlevel, as well as their 50 Hz (60 Hz)and 100 Hz (120 Hz) content. The in-strument automatically synchronizesto the line frequency.

TimeWithin the time mode, the AIAcompactdisplays five or ten AC cycles triggeredby a partial discharge event. Thus, thisdisplay shows the pattern of consecu-tive partial discharge events and,hence, offers a clear identification ofbouncing particles and the severity oftheir activity.All captured pattern and displays canbe transferred to a notebook via anRS232 interface using the optionalAIAcompact software.

PD •

19


Inst

rum

ents

RIVmeter

The RIVmeter is an instrument for the measurement of ‘Radio Influence Voltage’according to the relevant standards (NEMA 107-1987, ANSI 63-2-1996, VDE876, DIN EN 55016-1-1). The instrument has a bandwidth of 9 kHz and a tun-able center frequency of 10 kHz - 10 MHz. Technically, the RIVmeter is a selec-tive µV-meter. However, the meter reading is weighted according to the CISPRweighting curve, whereas the repetition rate has a strong impact on the reading.The RIVmeter is an ideal instrument to replace outdated RIV measurement in-struments in a transformer testing lab, for instance.

Some routine PD measurements are stilldone according IEEE Standards requir-ing the measurement of ‘RIV’ (RIV =Radio Influence Voltage). The RIV valueis given in µV (interference voltage). A‘narrow band’ filter performs a quasi-in-tegration of the PD pulses with a quasi-peak detection at the center frequency.This center frequency can be adjustedbetween 10 kHz and 10 MHz. The nar-row-band pass filter allows to suppressexternal noise e.g. in non-shielded labo-ratories by varying the center frequencyof the filter.

Two factors determine the RIV in µV:The transferred charge and the repeti-tion rate of the PD impulse (number ofPD pulses per second). Because of this

proceeding, a direct translation of themeasured RIV values (µV) into valuesof apparent charge in pC is not pos-sible.

Historically, the RIV technique is basedon measurement receivers to estimatethe disturbance of communication lines.Thus, properties of those instrumentsthen available became part of theNEMA standards. However, both the9 kHz bandwidth and the CISPRweighting curve put emphasis on somepartial discharge activity, while theytend hiding others.R

IVm

eter

- R

adio

Influ

ence

Vol

tage

Met

er

New RIVmetersupporting old standards

PD •




20

Old SiemensB83600-B40

1.00mV

HV off

CC

GND U

PD

CIL4M/V2µ0

C1

C2 BushingTap

CAL3A

connected forcalibration

disconnected during adjustment

REMOTE

Power DiagnostixBruesseler Ring 95a D-52074 Aachen +49 241 74927

S/N:000

The calibration of the RIV measure-ment is done using an RIV calibrator,injecting a sine wave of typically100 µV into the bushing. The multi-plexer of the RIVmeter is used to con-veniently determine the correction fac-tor according to NEMA 107-1987 andother standards. Here, the unit com-pares the voltage injected, i.e., loadedby the bushing’s impedance, with thevoltage detected at the bushing tap

RIVmeter rear panelCAL3A for RIV calibration

The RIVmeter is an instrument for the measurement of ‘Radio Influence Volt-age’ according to NEMA 107-1987 and other relevant standards. It is theideal instrument to replace outdated RIV measurement instruments in a trans-former testing lab.

Old Stoddart NM-25T

to automatically determine the k-fac-tor. This correction factor is thenstored independently for each chan-nel during calibration. The standardcalibrator for RIV calibration, CAL3A,offers a selectable frequency range of600-1350 kHz in steps of 50 kHz. Theoutput voltage covers 10 µV to 10 mVin 1-2-5 steps. The CAL3B calibratoroffers a frequency range of 400 kHzto 1.9 MHz with the same output volt-age but in steps of 100 kHz.

PD •

21


Inst

rum

ents

ICMflex

The ICMflex high voltage instrument family offers inherent operator safety andgreatly simplifies distribution class cable testing and other field tasks involvingpartial discharge and tanδ testing. With the unique concept of the ICMflex instru-ments, the entire acquisition hardware is placed on high voltage potential right atthe position where the signals are. Thus, no signal cables are needed, as theinstrument is fully self-contained and battery operated. The instruments are fullyremote controlled via high speed Bluetooth or fiber optic communication.

Unique ConceptThe ICMflex instrument family is avail-able with different options and for dif-ferent voltage levels. Additionally, theself-contained ICMflex acquisition unitcan be placed on top of any third-partycoupling or reference capacitor. Theoption TD offers tanδ and power factor(PF) measurements. The option PD pro-vides partial discharge measurementsaccording to the IEC60270, whereas theoption PDL includes partial discharge lo-cation for power cables.

Finally, the option TF covers a high volt-age T-filter to sufficiently de-noise a highvoltage supply for sensitive partial dis-charge measurements. The detachableLi-MH battery provides 10 hours of con-tinuous operation, while a second bat-tery is charged. Any high voltage AC

source can be used including resonanttest sets and VLF high voltage sources.

Testing distribution-class cables in afield environment becomes an easyand inherently safe task. The ICMflexunit is simply placed between high volt-age source and the cable to be tested– no further leads required. The ICMflexunit can be equipped with a high volt-age filter to accommodate noisy highvoltage sources. Thus, with one unitrequiring only high voltage and groundconnection all essential measurementson laid power cable are performed inone step: tanδ, partial discharge, andpartial discharge location.

Off-line testing of generator and motorstator coils is simplified in the same way.Using any high voltage source, the criti-cal AC measurements on the stator coilare done simultaneously: tanδ, PF, andpartial discharge.

ICM

flex

- Par

tial D

isch

arge

& ta

nδ M

easu

ring

Inst

rum

ent

Wireless signal transmissionvia Bluetooth communication

PD •




22

Using wireless Bluetooth or fiber optic technology the ICMflex tanδ and par-tial discharge analyzer family increases operator’s safety and greatly simpli-fies off-line testing and analysis of distribution class cables and rotating ma-chine stator windings.

Option TDThe tan delta analyzer uses an un-balanced bridge formed by internalshunt capacitors, the reference ca-pacitor and the device under test.Here, the ICMflex software showstanδ, PF, capacitance, voltage, andfrequency.

Option PDWith the option PD the ICMflex soft-ware offers a meter display accord-ing to IEC60270 and an oscilloscopicdisplay of the partial discharge activ-ity as well as a colored ϕ-q-n pattern

(above) based on the data receivedvia Bluetooth. Placing the quadru-pole and acquisition unit on high volt-age potential greatly improves thesensitivity and avoids any noisepickup on signal cables.

Option PDLThe partial discharge location optionuses high speed (100 Msample)sampling of the PD pulses travelingthe cable. Along with the analogbandwidth of 20 MHz this enablesprecise location and mapping of thedischarge activity along the cable.

ICMflex software with TD Option

ICMflex & HV filter

On-site cable testing

TD measurement onmotor bars

PD •

23


Inst

rum

ents

TDAcompact

The TDAcompact is a portable capacitance and tanδ analyzer. The focus of theinstrument's application is on the analysis of the epoxy-mica insulation of rotat-ing machines. Besides this, the unit is applicable for oil-paper insulation systemsand especially for mass-impregnated cables.

Analyzing the dissipation factor (tanδ)is a traditional method to assess thecondition of an insulation system. Withthe analysis of the dissipation factor, em-phasis is more put on the overall healthof the insulation system, whereas withpartial discharge analysis, the focus ison individual defects producing dis-charge activity. Therefore, the applica-tion of tanδ measurements concentrateson insulation systems, which are rela-tively stable against partial discharge.

Most prominently, the health of an ep-oxy-mica insulation of a rotating ma-chine can be assessed using a tanδanalyzer. Especially, the presence ofhumidity within the winding, the surfacecontamination of field grading ele-ments, or the polarization losses of im-properly cured resin, can be detected.Thus, the tanδ analysis is still a goodcomplement to the partial dischargetesting.

Dissipation Factor

Principle of OperationThe TDAcompact simultaneouslysamples the ac current drawn by thedevice under test and the current drawnby a reference capacitor. Subsequently,the two current traces are evaluatedand the capacitance, the tanδ, and thelevel of the high voltage are calculated.The unit continuously displays and re-freshes these results.TD

Acom

pact

- Au

tom

atic

C /

tanδ

Mea

surin

g In

stru

men

t

Portable and accuratetanδ analysis

PD •




24

Offering adequate resolution and accuracy as well as an unmatched port-ability, the TDAcompact is an excellent choice for field-type dissipation factormeasurements. Additionally, the TDAcompact can be used as a module of aflexible automated test system.

Therefore, the instrument does notrequire any user interaction as withthe traditional Schering Bridge, nordoes the refresh of the display takethat long as with automatic adjustingbridge-type analyzers. The basicresolution of the tanδ measurementis 10-4, which fulfills the requirementsfor rotating machine testing as wellas for testing on mass-impregnatedcables.

Stand-alone InstrumentThe TDAcompact is designed as astand-alone instrument. In its basicconfiguration, it comes with precisionshunts to measure the two currents.Optionally, the unit can be suppliedwith a normal capacitor.Generally, the TDAcompact is withdigital fiber-optic links to the precision

shunts, which allow operation on anypotential including the high voltageconnection of the device under test.The measuring frequency can varybetween 20 and 500 Hz or is fixed to0.1 Hz (VLF). Upon request, PowerDiagnostix can supply complete por-table tanδ testers including the highvoltage transformer.

Modular ConceptBesides the stand-alone field test ap-plication of the TDAcompact, the in-strument can also become a part ofa larger and automated test system.Using the software HVpilot, the instru-ment will be read according to a pre-programmed test sequence. Besidestanδ measurements, such automatedtest systems further include partialdischarge measurements and so-called step tests.

PD •

25


Inst

rum

ents

The HVcompact is a high voltage meter with an auto-ranging oscilloscope dis-play of the voltage waveform. The unit displays Û, Û/√2, Urms, frequency, and thecrest factor. To improve the readability, one selected measurement is displayedusing larger characters. To protect test specimens, the unit offers a pre-settablevoltage limit, which trips a relay output. The divider ratio is widely adjustable andis kept with a non-volatile memory.

HVcompact

saturation or power frequency harmon-ics, for instance, are clearly identifiedwith this display. The screen is automati-cally synchronized with the measuredvoltage and the amplitude deflection iscontrolled by an auto-range function.

Mostly, the HVcompact is used in caseof modernization or upgrade of high volt-age test sets. With conventional ana-log or digital panel meters, usually,solely the voltage is displayed. TheHVcompact adds several helpful func-tions.

Oscilloscopic DisplayThe input voltage is sampled in highresolution and one cycle is displayed asan oscilloscopic trace. Any distortion ofthe high voltage due to transformer core Measurements

Usually, the instrument connects to ca-pacitive or resistive divider. With largerhigh voltage transformers, the capaci-tance of the condenser bushing can beused. Within the menu of theHVcompact the divider ratio can be ad-justed. It is kept with a non-volatilememory. The nominal input range of theHVcompact is 100 Vrms. In order tocover correctly even strong harmonics,peak voltages of up to 200 V are ac-cepted and sampled.

Scope display of the waveformHVc

ompa

ct -

Hig

h Vo

ltage

Met

er

All voltage informationat a glance

PD •




26

Using the sampled voltage, the instru-ment calculates based on the presetdivider ratio the characteristic quanti-ties of the high voltage signal. Withthe upper two lines of the display thepeak voltage Û, the peak voltage di-vided by the square root of two Û/√2,and the effective voltage Urms is shown.Additionally, the crest factor is calcu-lated and displayed. With the bottomline of the display, the frequency ofthe captured voltage signal is shown.This bottom line further shows thescaling of the Y-axis grid of the oscil-loscopic display. One selected valueis displayed using larger characters forimproved readability.

Safety FeaturesA voltage limit can be set with the in-strument in order to avoid that a testspecimen is stressed above its allow-able voltage. In case the voltage thenexceeds this limit, a relay is tripped.This relay can be used to block the'UP' button of the control circuit or todisconnect the main circuit breaker.Additionally, the instrument detects in-cipient breakdown or flashover. There-fore, a maximum permissible voltagechange per second (dU/dt) can be set.

Each individual cycle of the high volt-age signal is analyzed. Especiallywith long-term voltage endurancetests, this feature can minimize thethermal destruction of the breakdownchannel and, thus, improves theanalysis of the defect.

Optional REC OUTThe HVcompact is available with anoptional recorder output. In case, aconnector carries a re-converted ana-log (DC) signal of 0-10 V, which cor-responds to the high voltage signal.This signal can be fed to a paper re-corder, for instance. A screw termi-nal carries the optional relay outputsignals for voltage limit and break-down detection.

Giving an instant display of all relevant parameters of a high voltage signalincluding an oscilloscope trace makes the HVcompact an ideal upgrade forhigh voltage test rooms. Additionally, the HVcompact detects incipient break-down and keeps a record of the voltage history.

By end of 2003, Power Di-agnostix received the ac-creditation as calibration

laboratory within the German Calibra-tion Service (Deutscher Kalibrier-dienst, DKD). The audit was held by'Physikalisch Technische Bundes-anstalt' PTB, the German authority ofstandards. Power Diagnostix accredi-tation is filed under DKD-K-31101.

In 2006, Power Diagnostix extendedthe accreditation by AC high-voltagesup to 100 kV. On order theHVcompact can be calibrated on sitetogether with its divider impedance.

0606000

DKD-K- 3110106-06

0606000

DKD-K- 31101

06-06

Calibration

PD •

27


Inst

rum

ents

STEPcompact

Increasing the high voltage stepwise is a task that is often required during typetesting and production testing of high voltage products. The STEPcompact is aninstrument to automate such step tests. The unit combines the control functionwith the measurement capabilities of a high voltage meter. As a stand-aloneinstrument, the STEPcompact can be easily moved between different high volt-age test sets.

Running step test sequence

The STEPcompact measures the volt-age signal derived from a capacitive orresistive divider. Using a fiber optictransmission, the UP and DOWN relaycontacts of the voltage regulator are ac-tuated to adjust the high voltage accord-ing to the programmed test sequence.

FeaturesSimilar to the HVcompact, the instrumentcalculates and displays the characteris-tics of the captured high voltage signalsuch as Û, Û/√2, Urms, frequency, and thecrest factor. The unit accepts a nominalinput voltage of 100 Vrms. In order to cor-rectly acquire even excessively distortedhigh voltage signals, the STEPcompactsamples up to 200 V peak signals.

Using the five menu-driven controlbuttons, up to 35 different test se-quences can be programmed andstored in a non-volatile memory. A test

sequence consists of steps andramps in any order. Besides the au-tomatic mode, a manual mode can beused to set a specific voltage andkeep it over time. In factory environ-ments with strongly varying load situ-ations, this function can be very help-ful to maintain a stable high voltagelevel with long-term tests.Up to seven configurations can bestored in the non-volatile memory inorder to adapt the instrument to theproperties of different high voltagetest sets. Besides the divider ratio, aconfiguration setup contains settingssuch as the control cycle or the con-trol window to tune the instrument tothe properties of the high voltage testset.ST

EPco

mpa

ct -

Step

Vol

tage

Con

trol

ler

Safety and automation forstep test sequences

PD •




28

HVpilot software

In the standard configuration, theSTEPcompact comes with a self-con-tained relay box that is remotely con-trolled via a fiber optic cable. Alterna-tively, a direct connection to theHVcontrol, Power Diagnostix standardcontrol unit for high voltage test sets,can be provided.To ensure a safe unattended process-ing of a step test, the STEPcompactoffers several safety features. Incipi-ent breakdown is detected by moni-toring the change of the voltage (dU/dt). Further, timeout limits can be set.The instrument keeps a record of therecent test to validate its successfulcompletion or to indicate the point ofbreakdown or cancellation.

HVpilot SoftwareThe HVpilot software allows the com-plete supervision of a high voltagetest sequence. Using a serial inter-face, the software connects to theSTEPcompact for the voltage controland measurement. Further, theHVpilot software offers convenientprogramming and editing of the testsequences. Additionally, this softwarecan connect to the ICMcompact toread the partial discharge level andto the TDAcompact to read the tanδas well as the capacitance of the de-vice under test. An export functionallows to save the acquired data infile formats for MS-Excel and MS-Word.

Offering complete measurement of high voltage signals plus flexible pro-gramming of step test sequences makes the STEPcompact an ideal andcost-effective solution to automate high voltage test sets. The optional soft-ware HVpilot offers convenient programming and reporting.

PD •

29


Inst

rum

ents

HVcontrol

HVcontrol embedded in a control desk

The HVcontrol unit combines all standard functions required to manually operatea high voltage transformer. It includes a safety contact loop, the measurement ofprimary and secondary current, as well as of the primary voltage. User-settablelimits for the primary and secondary current trip the main circuit breaker. Thesafety loop, as well as the emergency stop is hard-wired and equipped withforced contacts.

Due to its flexible design, the HVcontrolcan be used on any high voltage test set.Especially, in case of the modernizationof old test sets, the HVcontrol offers amultitude of improvements if comparedwith conventional relay based controls.

The unit comes with rigid solid-statepiezo push buttons. Each of these con-trol buttons has an illuminated ring toindicate the state of the function con-trolled by this specific button. This allowsan easy and intuitive operation of theHVcontrol.

The HVcontrol comes in a 19"-subrack(3HU). This makes it an easy replace-ment of older controls having the samesize. On its rear panel, the HVcontroloffers conveniently detachable screwterminals for the different controls andoptional instruments.

Modular ConceptBesides a mere drop-in replacement ofan old control, the HVcontrol can becombined with other test instruments ofPower Diagnostix to build a fully auto-mated acceptance test environment.On its rear panel, the HVcontrol is pre-pared to directly connect to theSTEPcompact, Power Diagnostix in-strument for the automation of test se-quences (step test).

HVc

ontr

ol -

Hig

h Vo

ltage

Tes

t Con

trol

Uni

t

Drop-in replacementof old control units

PD •




30

Block diagram for the connection of a HVcontrol

Control and measurement system

Inter-lock

HVcontrol

U

I I

ICMcompact

STEPcompact

IPC

TDAcompact

Isec UsecUprim, Iprim

HornLamps• •

Further, the instrument can be com-bined with the ICMcompact for partialdischarge testing and with theTDAcompact for tanδ and capacitancemeasurements.

programming and editing of the testsequences. Additionally, this softwarecan connect to the ICMcompact toread the partial discharge level and tothe TDAcompact to read the tanδ aswell as the capacitance of the deviceunder test.

Easily replacing out-dated control units of high voltage test sets make theHVcontrol a good choice when modernizing high voltage test labs. Addition-ally, the HVcontrol is prepared to interface with the STEPcompact for auto-mated high voltage tests.

Power Diagnostix also provides indus-trial PC's to control the combinationof instruments. Depending on the ap-plication and its requirements, the in-struments can be mounted in desk-top enclosures, 19" racks, or controldesks fitted with 19" mounts.

HVpilot SoftwareThe HVpilot software allows the com-plete supervision of a high voltage testsequence. Using a serial interface,the software connects to theSTEPcompact for the voltage controland measurement. Further, theHVpilot software offers convenient


Fully automatedtest systems

PD •

31


Inst

rum

ents

FOsystem

The FOsystem is a complete set of instruments for convenient fiber optic trans-mission of different types of analog signals from a variety of sensors. TheFOsystem allows easy implementation of fiber optic transmission to solve noise,safety, and signal quality issues in high-voltage measuring environments andother demanding conditions. The signal bandwidth covers DC up to 10 MHz.

Fiber Optics vs. WiringHarsh electromagnetic conditions preva-lent in high-voltage and high-currentlaboratories seriously interfere with theuse of conventionally wired measuringequipment. Fiber optic cables that arenot prone to electromagnetic interfer-ence can replace even long BNCcables.Applying fiber optic isolation with highimpulse-current applications allows theground potential to have dramaticallytransient changes without affecting theintegrity of the signals captured andtransmitted.

System ComponentsThe Power Diagnostix FOsystemcomes in three basic variations, foreach of three signal types:• FOS1 for analog transmission of ana-

log signals from DC up to 10 MHz• FOS2 for digital transmission of ana-

log signals from DC up to 20 kHz• FOS3 for pulsed digital transmission

of slowly changing signals such astemperatures.

• FOS4 for digital transmission of ana-log signals from DC up to 65 MS/s

All versions consist of transmissionunits, receiver units, and sturdy fiberoptic cable.The fiber optic transmitter modules(FOT) are small individual modules forinstallation at sensors or signal sources.The fiber optic receiver modules (FOR)are mounted side-by-side in a 19-inchor half 19-inch rack.

Fiber Optic Transmitter FOT1/5FOsy

stem

- Fi

ber O

ptic

Sig

nal T

rans

mis

sion

PD •




32

Conveniently providing robust fiber optic transmission of analog signals inhigh-voltage environments, the Power Diagnostix FOsystem solves signalintegrity problems and safety issues found with severe electromagnetic con-ditions and long distances.

OperationThe output signal of the signal sourceor sensor (for example, voltage, dy-namic pressure, current, or partial dis-charge) is fed to the input of the FOT.The transmitter then either modulatesthe infrared light emitted by the trans-mitter diode according to the value ofthe input signal (amplitude modula-tion, FOS1), or digitizes the signal andtransmits a digital telegram. This opti-cal signal is transmitted via the fiber

Acoustic sensor

Transmitter unit

Receiver (3 channels)

Temperaturemeasurement

(including receiver)

to the receiver, which converts it backto voltages for further processing.

The transmitter is installed in a cast-aluminum enclosure. The FOT is fit-ted with a NiMH-battery for a mini-mum operating time of twenty hours(FOT1 and 2), whereas the FOT3 of-fers up to two years of operation whilesending a telegram every five sec-onds.

Type Option FOS1 FOS2 FOS3 FOS4FOT1 Analog transmitter 0.2 Hz - 5 MHz (-3dB) XFOT2 Digital transmitter 0 - 20 kHz (-3dB) XFOT3A Transmitter for temperature measurement XFOT3B Transmitter for voltage and current XFOT4A Digital transmitter up to 65 MS/s, (30 MHz bandwidth) XFOT/S2 Pressure measurement XFOT/S3 Fixed DC coupling X X XFOT/S4 Switched DC coupling X XFOT/S6 Remote activation X XFOT/S7 Special input range X X XFOT/S8 Pressure measurement (Kistler 6203 sensor) XFOT/S9 Displacement measurement XFOT/S10 Bandwidth 10 MHz XFOT/S12 S12, ultrasonic measurement X XDIV10 Pre-divider 1:10 (BNC-BNC) X X XDIV100 Pre-divider 1:100 (BNC-BNC) X X XDIV1000 Pre-divider 1:1000 (BNC-BNC) X X XFOR1 Receiver plugin 0.2 Hz - 5 MHz XFOR2 Receiver plugin 0 - 20 kHz XFOR3 Receiver plugin FOR3 XFOR4 Receiver plugin up to 65 MS/s, (30 MHz bandwidth) XFOR/E2 DC coupling, track/hold switch XFOR/E3 DC coupling, adjust button XFOR/E5 1.2" width, output on rear side X XFOR/E6 Bandwidth 10 MHz XFOR/E7 Bandwidth limit 1 MHz, noise reduction XFOR/E8 1-channel remote transmitter XDR42 Desktop rack ½ 19" X X X XDR84 Desktop rack 19" X X X X

PD •

33


Inst

rum

ents

FOsystem (FOS4)

The latest family member of Power Diagnostix' fiber optic transmission systems,FOS4 offers high speed data acquisition via fiber optic cables on multiple chan-nels in parallel. The scalable system allows the acquisition of acoustic PD sig-nals or other measurement signals under AC, DC, or impulse testing in laborato-ries as well as on site. The modular system accepts up to twelve optical channelsand comes with high-speed controller card to communicate with a notebook.Besides this, the FOS4 system has additional signal output on the rear side andcan be used as a digital isolated amplifier without the use of any software.

Acoustic location of PD on upto 12 channels in parallel

FOS4

- Ac

oust

ic L

ocat

ion

of P

artia

l Dis

char

ge

Application ExamplePD Location by acoustic travel time ana-lysis (ICMacoustic)

The ICMacoustic system comprises ofFOT4 transmitter units and FOR4D re-ceiver units. Each channel acts as anindependent transient recorder with itsown storage and settable acquisitionspeed and storage depth. The samplingrate is 20Msample/sec. and, hence, suf-

ficient to even acquire the pointing vec-tor of the incoming acoustic wave, whenusing a two-dimensional three-sensorconfiguration.

For PD location purposes theICMacoustic software offers full controlof the system.

Features:• Sampling rate: 65 MS/s• Up to 12 receiver units with indepen-

dent optical channels• Remote controlled via high speed

USB port

PD •




34

ICMacoustic system

Measurement panel for horizontal and vertical triangulation

With its versatile front end the FOS4 is a stand-alone fiber optical measure-ment equipment that allows to easily perform electrically isolated measure-ments with a variety of setting options. All parameters can be set either fromthe front side of the FOR4 device or via the ICMacoustic software.

ICMacoustic SoftwareThe ICMacoustic software offers fullcontrol of the FOS4 system includingaveraging and trigger logic. It is de-signed for the acoustic location oftransformer partial discharge with thetriangulation method. The basic ideais to reduce the location to a “flat prob-lem”. I. e., to horizontally position threesensors on a line to firstly get the hori-

zontal position of the layer (see up-per graph of the software’s measure-ment panel, left). Here, the positionof the sensors are entered and as-signed to their channel. In a secondstep the sensors are placed on a ver-tical line at the found vertical position.In the lower graphs the sensor posi-tions are entered accordingly.

PD •

35


Inst

rum

ents

ATTanalyzer

The Power Diagnostix ATTanalyzer is a simple and effective stand-alone tool toaid in commissioning tests of gas-insulated switchgear (GIS) systems and powertransformers. The ATTanalyzer reduces delays in commissioning and mainte-nance by locating flaws in GIS systems and transformers acoustically.

Gas-insulated switchgear systems oc-casionally contain flaws that go unno-ticed during installation or maintenancebut that lead to immediate breakdownwhen high voltage is applied. Theseflaws can include floating particles, gas-eous impurities, faulty insulator discs,sharp metal burrs, or other defects. If agas-insulated switchgear system con-tains such a flaw when brought on-line,sparking and breakdown occurs at theflaw, forcing de-energization and repair.Without diagnostic aids, location of theflaw can lead to costly delays and un-necessary opening of unflawed gaschambers bearing the risk of causingnew imperfections, while searching forthe chamber containing the flaw.Using the ATTanalyzer, the flaw can belocated by mounting acoustic sensorsto the outside of the GIS or transformertank in several locations. When highvoltage is applied to the GIS, if a break-down occurs, the acoustic sensors pickup the disturbance and transmit a cor-responding optical signal to theATTanalyzer acquisition unit. The

ATTanalyzer then compares the rela-tive travel times of the sound signals todetermine which sensor is the closestto the flaw.Following initial location of the break-

down’s origin, the acoustic sensors canoptionally be repositioned closer to theflaw to narrow the location further, towithin a few centimeters. Comparingthe resulting display with the display ofthe breakdown while using a hammerto trigger a similar pattern on theATTanalyzer, further helps to narrowdown the location of the flaw.

Fiber optic connectors of the ATTanalyzer

ATTa

naly

zer -

Aco

ustic

Bre

akdo

wn

Loca

tion

PD •




36

System ComponentsThe ATTanalyzer consists of a com-pact central acquisition unit, acousticsensors, and sturdy fiber optic cableto connect the sensors to the acquisi-tion unit.The stand-alone ATTanalyzer acqui-sition unit, mounted in a half-19-inchrack, receives and internally pro-cesses signals picked up by the sen-sors. The acoustic sensors for exter-nal mounting on the GIS system canbe easily attached and removed forreuse. Up to sixteen sensors can beconnected to the ATTanalyzer.Fiber optic cables, up to 200 metersin length, provide galvanically isolatedconnection of the sensors to theATTanalyzer acquisition unit.

FeaturesThe ATTanalyzer’s embedded LCDpanel displays the relative travel timesfrom the sensors as horizontal bars.Cursors and settings are manipulatedthrough pushbuttons and on-screenmenus.

The display screen also shows rel-evant quantities such as samplingrate, time between cursors, time anddate stamp, etc.Using simple menus, users can ad-just the sampling rate of the acquisi-tion unit appropriately depending onhow widely or closely spaced thesensors are to each another.TheATTanalyzer features storage of upto sixteen GIS fault events with timeand date stamps. Users can chooseone of three operating modes:AUTO This mode considerseach trigger event. Thus, the instru-ment's memory contains the mostrecent 16 events.NORM Using this mode, the unitchanges to the STOP mode after 16events captured. Therefore, thememory contains the first 16 events.SINGLE This mode changes aftereach captured event into STOPmode. Changing manually back intoRUN mode re-enables triggering.

Offering easy implementation and convenient data analysis, the PowerDiagnostix ATTanalyzer aids in cost-efficient location and repair of gas-in-sulated switchgear and transformer defects during commissioning tests.

ATTanalyzer monitors a long-term test on GIS spacers and insulators (SIEMENS)

PD •

37


Inst

rum

ents

GIS

mon

itor -

PD

Mon

itorin

g on

GIS

Sys

tem

s

GISmonitor

The GISmonitor builds on 15 years experience in online PD monitoring on rotatingmachines, transformers, cables, and especially GIS systems. It combines proventechnology of the ICMmonitor with new processor technology and embeddedhardware capabilities. The hardware core of the system has been optimized forparallel, real time PD acquisition on multiple channels. Any UHF signal can bedetected and digitized within micro seconds. A separation of PD events fromexternal disturbances or internal switching pulses is calculated in real time andtherefore an effective PD and alarm detection is given.

Each 8-channel acquisition plug-in ope-rates fully stand alone, but can be com-bined with a virtually unlimited number ofunits, to monitor all PD sensors in one GISPD monitoring system in parallel. A full 19"sub-rack carries 64 channels. A remotecomputer reads all data of the instrumentsvia the high speed Intranet or USB bus.System redundancy is provided due to thelocal memory storage capacity on eachacquisition unit. The GISmonitor indicateswith on-board LED’s internal states andalarm conditions.Two main 19” racks are used to accom-modate all instruments and the industrialPC. Each rack comes with a standard19” frame, non-interruptible power sup-ply, network switch and temperaturecontrolled fans. With each installationmultiple monitoring instruments areplaced in one 19” rack. All cables fromexternal are feed through the rear sideinto the rack. Alternatively a customizedBNC patch board can be ordered.

Features• Parallel UHF PD measurement on all

channels• Parallel reading of PD peak values, PD

scope amplitudes, and PD patterns• Separate gating input channel• Automatic alarm detection system• System redundancy• Suitable for embedded and external

retrofit UHF sensors• Scalable system configuration• Automatic noise suppression mode• Network-based communication

The GISmonitor is designed to suit allcurrently available UHF sensors forGIS PD monitoring. This includesembedded and external retrofit UHFsensors. A special input protection unit(IPU2) blocks strong transients (VFT).The preprocessing unit (FCU orRPA6C) demodulates pulse UHFsignals into a lower frequency band.

PD •




38

The user interface software panel ofthe GISmonitor monitoring system isinstalled on the local industrial PC andcan be installed additionally on anyremote computer for data evaluationand diagnosis. Using an administrativesetup allows configuring the systemand the embedded service program.

Software Features• User friendly software panel includ-

ing a customized GIS overview dia-gram indicating all sensors and itscurrent activities

• Additional analysis and trendingpanel displaying Qp, NQS, scope,and pattern information of eachchannel at every time stamp

• Alarm event list indicating peaklevels, PD patterns and trendinformation

• PD trending and PD patterninformation of the full history

• Typical PD failure database• Automatic data storage• FTP access• Interface to third party control

systems, such as SCADA,DNP 3.0, MODBUS, IEC61850,and others.

This service program takes care ofreading data and alarm conditions fromthe instruments in a predefined timeschedule. The service starts as soonas the computer has been turned onand, hence, a valid login on thismachine is not mandatory to continuethe data acquisition.

The GISmonitor is a scalable monitoring device for continuous monitoring ofgas-insulated switchgear (GIS) using true prarallel, real-time acquisi-tion techniques.

Real time parallel PD acqui-sition on multiple channels

PD •

39


Acc

esso

ries

ICMseries Accessories:Preamplifiers

Preamplifiers serve to condition, filter, and amplify the partial discharge signal tobe measured. Because the frequency range in which PD signals are measuredis strongly dependent on the preamplifier used, proper selection of a preamplifieris an important part of noise mitigation and can have a strong effect on theappearance of the partial discharge pattern itself.

All of the Power Diagnostix external sig-nal conditioning modules and pream-plifiers are remote supplied and remotecontrolled through a simple coaxial sig-nal cable (RG58). This technique allowsplacement of these units close to thesensor or signal source. Furthermore,as these modules act as impedanceconverter and line driver, the weak sig-nal source, such as voltage divider orcoupling impedance, is not loaded bythe cable capacitance or impedance.This technique also provides enhancedover-voltage protection. All preamplifi-ers of the RPA series can drive a 50 Ωcable up to 50 m long.The RPA1 is the standard preamplifierfor measurements in the low frequencyrange according to standards such asthe IEC60270. The RPA1B, RPA1C andRPA1D are variations on the RPA1.RPA1B and RPA1C will put the signalthrough when the supply is turned off.

Power Diagnostix provides a completeline of modular preamplifiers for varioustesting applications. The most significantdifference among the preamplifiers is thefrequency range in which they detect par-tial discharge signals. Other features thatdistinguish one preamplifier from anotherare: options for transparency and on/offswitching, unipolar vs. bipolar charge de-tection, and the possibiltiy of galvanic iso-lation in the test setup.

A few of the RPA series of preamplifiers

The RPA1 preamplifier(size approx 100 mm x 65 mm)

Acc

esso

ries

- Pre

ampl

ifier

s

PD •




The versatility of the Power Diagnostix line of PD detection equipment is duein large part to the range of accessories available for the ICMseries instru-ments. Each ICMseries data acquisition unit can be combined with differentaccessories to suit specific applications.

The RPA1D is suited to connect di-rectly to ultra-sonic acoustic sensors.To simplify connection, the RPA1Dprovides selectable power supply forthe sensor (15 V or 28 V DC).The RPA1L and RPA1H are intendedprimarily for measurements on me-dium and high-voltage power cablesusing the ICMcompact.The RPA2 is primarily for measuringthe PD signal spectra found with ro-tating machines, while the RPA2B isused with capacitive sensors to moni-tor cables and cable accessories at ahigher sensitivity.The RPA3 module is well-suited formeasuring PD signal spectra, detectedby sensors and antennas installedwith gas insulated switchgear (GIS).The RPA4 is a preamplifier set withfiber optic transmission, offering out-standing isolation properties.

The RPA6 allows selecting one ofthree frequency ranges according tothe particular application. The loga-rithmic RPA6 is mainly used withmonitoring applications, and as a ver-satile preamplifier for noise gating.The RPA6C is an ultra-wide bandversion of the RPA6, covering300 MHz to 2 GHz. This preamplifieris mainly used for GIS monitoring withthe ICMmonitor.The UHF1 offers an amplification of27 dB in the range from 200 MHz to1 GHz, and is suitable for boostingweak signals from GIS sensors.The HST1B is an impedance con-verter for the measurement of volt-ages. The input impedance is as highas 10M Ω and ideal to measure thelow-voltage wave from e.g. a voltagedivider. The output is to be connectedto the SYNC IN of the ICMsystem.

Ref

eren

ce ta

ble

for c

omm

only

use

dP

ower

Dia

gnos

tix p

ream

plifi

ers T

ype

Fre

quen

cy ra

nge

Inpu

t im

peda

nce

Inpu

t s

ensi

tivity

Rol

l-off

Bip

olar

Rem

arks

RPA1 40 kHz–800 kHz 10 kΩ/ /50 pF <200 µV 40 dB/dec ü Standard preamplifierRPA1D 40 kHz–800 kHz 10 kΩ/ /50 pF <200 µV 40 dB/dec ü W ith built-in sensor supplyRPA1E 40 kHz–800 kHz 10 kΩ/ /50 pF <200 µV 40 dB/dec ü 0/20 dB attenuationRPA1F 40 kHz–800 kHz 10 kΩ/ /50 pF <200 µV 40 dB/dec ü For the AIAcompac t onlyRPA1G 40 kHz–800 kHz 10 kΩ/ /50 pF <200 µV 40 dB/dec ü Like RPA1D but switchableRPA1H 40 kHz–20 MHz 1 kΩ// 5 0 pF <400 µV 40 dB/dec ü Oil/paper cable, DSORPA1L 40 kHz–20 MHz 1 kΩ// 5 0 pF <200 µV 40 dB/dec ü Cable, DSORPA2 2 MHz–20 MHz 50 Ω/ /5 0 pF <800 µV 40 dB/dec Rotat ing machinesRPA2B 2 MHz–20 MHz 50 Ω/ /5 0 pF <200 µV 40 dB/dec Cable sensorsRPA3 200 MHz–1 GHz 50 Ω/ /5 0 pF <300 µV 40 dB/dec GIS sensorsRPA3D 50 MHz–400 MHz 50 Ω/ /5 0 pF <300 µV 40 dB/dec Nearfield detec tionRPA3E 20 MHz–200 MHz 50 Ω/ /5 0 pF <300 µV 40 dB/dec Nearfield detec tionRPA4 40 kHz–800 kHz 10 kΩ/ /50 pF <200 µV 40 dB/dec ü Fiber opt ic isolationRPA6 40 kHz–800 kHz

2 MHz–20 MHz200 MHz–500 MHz

10 kΩ/ /50 pF50 Ω/ /5 0 pF50 Ω/ /5 0 pF

<200 µV 40 dB/decFor gating, selec table frequency range, logarithm ic output

RPA6C 300 MHz–2 GHz 50 Ω/ /5 0 pF <200 µV 40 dB/dec Logarithm ic outputUHF1 200 MHz–1 GHz 50 Ω/ /5 0 pF -- -- GIS , sensorsUHF2 300 MHz–2 GHz 50 Ω/ /5 0 pF -- -- GIS , sensorsHST1B 20 Hz–400 Hz 10 MΩ/ /2 0 0 pF -- -- ü ICMsys tem , SYNC IN

PD •

41


Acc

esso

ries

ICMseries Accessories:Quadrupoles & Isolation Transformer

CIL/V QuadrupoleThe CIL/V quadrupoles are similar to theCIL quadrupoles but also contain a ca-pacitor acting as a voltage divider to-gether with the high voltage coupling ca-pacitor. This provides a low-voltage copyof the applied high-voltage wave thatcan be used through a HST to synchro-nize the PD detector and monitor thequality of the applied high-voltage wave.

When a quadrupole and a coupling capacitor are used together as the couplingdevice, high voltage is applied both to a test object and to the coupling capacitorin parallel with the test object. A quadrupole (sometimes called a measuring im-pedance) can then be placed in series with either the coupling capacitor or inseries with the test object. Some quadrupoles also output a low-voltage copy ofthe applied high-voltage wave for synchronizing the PD detector. The three basicmodels of available Power Diagnostix quadrupoles are briefly described here.

CIT QuadrupoleThe CIT coupling units are transformertype units, where a preamplifier’s inputresistance functions as the requireddamping resistor. CIT units offer a highersensitivity than the CIL coupling units.Furthermore, CIT units are available forbridged configurations to connect to twosimilar test objects as well.

CIL/V QuadrupoleOptionally, the quadrupoles with built-individer capacitor for voltage measure-ment can be supplied with a rotary switchto select the divider capacitor. Especially,when connected to the measurement tapof transformer bushings, the selectablecapacitors expand the applicable voltagerange.

CIL QuadrupoleThe CIL quadrupoles consist of an in-ductor in parallel with a damping resis-tor. The inductor and resistor are calcu-lated to form, together with a high-volt-age coupling capacitor, a second orderhigh pass filter. Therefore, match ingthe range of the CIL with the size of thecoupling capacitor with which it will beused is important.

Acc

esso

ries

- Qua

drup

oles

& Is

olat

ion

Tran

sfor

mer

PD •





Ref

eren

ce ta

ble

of s

tand

ard

Pow

er D

iagn

ostix

qua

drup

oles

IT Isolation TransformerThe IT-series allows the isolation of 250 voltsbetween input and output permanently. Itshigh frequency behavior is optimized for50Ω-systems and the use with a multiplexerand RPA2 or RPA2B type of preamplifier. Anextra voltage output ‘/V’ with the 50/60Hz fun-damental frequency is available on request.

Typ

e

Tran

sfor

mer

Typ

e

Vol

tage

Ran

ge a

t 5

0Hz

and

CC m

ax.

Cou

plin

g C

apac

itor

Ran

ge

AC

Cur

rent

Ran

ge

Isol

ated

Inpu

t

Mea

sure

men

t at

HV

Cab

les

50 O

hm M

atch

ed

Opt

. Bal

ance

d M

ode

(Tw

o Br

idge

d In

puts

)V

olta

ge D

ivid

erC

apac

itor

(to b

e sp

ecifi

ed)

CIL3M 400 kV 200pF – 800pF 100 mACIL4L 125 kV 600pF – 2.5nF 100 mACIL4M 500 kV 600pF – 2.5nF 400 mACIL4 1000 kV 600pF – 3.5nF 1.1 ACIL5L 125 kV 2nF – 9nF 350 mACIL5M 250 kV 2nF – 9nF 700 mACIL5 1000 kV 2nF – 12nF 3.8 ACIL6M 125 kV 6nF – 35nF 1.4 A

CIT4M 1000 kV 600pF – 2.5nF 800 mA

CITS4M 1000 kV 600pF – 2.5nF 800 mA

CIT4 1000 kV 600pF – 3.5nF 1.1 A

CIT5M 500 kV 2nF – 9nF 1.4 A

CITS5M 500 kV 2nF – 9nF 1.4 A

CIT5 1000 kV 2nF – 12nF 3.8 A

CIT6M 180 kV 6nF – 35nF 2.0 A

CITS6M 180 kV 6nF – 35nF 2.0 A

All

CIL

and

CIT

are

ava

ilabl

e w

ith o

ne o

r tw

o(s

witc

habl

e) b

uilt-

in d

ivid

er c

apac

itors

to

prov

ide

avo

ltage

out

put s

igna

l, m

arke

d by

'/ V

'.

Type Max. ACCurrent

Max. Voltage(< 1 minute)

-6dB LFCut-Off

-3dB LFCut-Off

-3dB HFCut-Off

-6dB HFCut-Off

InputConnector

IT2 500mA 10kVAC 200kHz 350kHz >30MHz >50MHz BNCIT3B 1000mA 500VAC 100kHz 200kHz >30MHz >50MHz BNCIT4B 1000mA 500VAC 100kHz 200kHz >30MHz >50MHz Banana

PD •

43


Acc

esso

ries

ICMseries Accessories:Coupling Devices & Filters

The Power Diagnostix line of coupling devicesincludes quadrupoles, current transformers, andcoupling capacitors to adapt Power DiagnostixPD detectors to different measurement tasks.The coupling device in a PD measuring circuitprovides the means of sensing the partial dis-charge pulse and sending it as a voltage signalto a preamplifier for conditioning.

The coupling device can be a capacitor and aquadrupole, a capacitor and a current trans-former, or a current transformer alone. The stan-dard capacitor for tanδ measurements, such asthe SC30, consists of a capacitor and a built-inshunt capacitor, only. Additionally, combinedunits for tanδ and partial discharge measure-ments are available.

Coupling CapacitorsPower Diagnostix standard coupling capacitors are mounted on sturdy cast alu-minum enclosures and can be used for on-line and off-line measurements on

Standard coupling capacitorsand supplementary circuits

rotating machines as well as for a va-riety of smaller test setups. A widerrange of coupling capacitors and ca-pacitor assemblies complete with qua-drupoles and preamplifiers is availableon request. The table below lists somestandard models of coupling capaci-tors provided by Power Diagnostix,along with their built-in circuits, ifpresent.

Coupler termination box

CTB

1

Type channel sparkgap

IN OUT

CTB1A 3x 350V BNC BNCCTB2A 4x 350V BNC BNCCTB2C 4x 350V TNC BNC

Type

Cap

acita

nce

Nom

.Vol

tage

Built

-in Q

uadr

upol

eBu

ilt-in

Vol

tage

Div

ider

Built

-in R

F C

T

max

. Hei

ght [

mm

]

CC14B 220 pF 14 kV ü ü 190CC20A 145 pF 21 kV ü 300CC20B 145 pF 21 kV ü ü 300CC25A 1 nF 25 kV ü 300CC25B 1 nF 25 kV ü ü 300CC25B/V 1 nF 25 kV ü ü 300CC25C/V 1 nF 25 kV ü ü ü 300CC35B 145 pF 35 kV ü 310CC35B/V 145 pF 35 kV ü ü 310CC50B/V 500 pF 50 kV ü ü 500CC50C/V 500 pF 50 kV ü ü ü 500CC100B 1 nF 100 kV ü 695CC100B/V 1 nF 100 kV ü ü 695CC150B/V 1 nF 150 kV ü ü 1210CC200B/V 0.5nF 200 kV ü ü 1300

Acce

ssor

ies

- Cou

plin

g D

evic

es &

Filt

ers

PD •




44


Type Name UN INSize

(WxHxD)cm

PI 1/120 1 kV 120 Aπ-Filter

PI 20/5 20 kV 5 A 50x47x353PI 1.5/50 1.5 kV 50 A 40x17x463PI 1/20 1 kV 20 A 40x17x463x π-Filter3PI 2/20 2.2 kV 20 A 40x17x46T 70/60 70 kV 60 A 50x100x45T 85/60 85 kV 60 A 50x100x45T-FilterT 100/100 100 kV 100 A 50x100x45TCC 30/1 30 kV 1 A 50x67x35TCC 50/1 50 kV 1 A 50x80x35

T-Filterincl. coupling capacitor TCC 65/10 65 kV 10 A 50x100x45

FilterPartial discharge measurements are con-ducted in frequency ranges, which arepartly covered by radio transmission. Fur-ther, impulse noise interference hampersensitive measurements. Besides usingsmall filters in the acquisition chain, powerfilters allow removing such disturbancefrom the high voltage supply. PowerDiagnostix offer a range of different highvoltage filters. Standard filters are availablefor induced voltage testing on large powertransformers. Here, the rated voltage is70 kV at a permanent current of 60 A (shortduration: 100 A).

HV Filter T70/60

TCC50Filter & Coupler

T70/100

3PI 2/20 Filter

PI 20/5 Filter

PD •

45


Acc

esso

ries

ICMseries Accessories:Sensors and Miscellaneous

WS80 / 95 / 140 Window SensorExternal window sensors are used toconveniently equip older GIS with UHFmonitoring. Power Diagnostix offerssuch window sensors of different sizesto fit the inspection windows of olderGIS. Instead of embedded sensors, ad-ditionally, modified earthing switchescan be used. In case of non-shieldedsupport insulator disks a proven methodis to apply ring antennas to capture theUHF signals at the flanges. WS Window sensors in different sizes

EFS1 Sensor

EFS1 sensorThe external flange sensor EFS1 is awide-band UHF antenna for PD detec-tion on GIS and GIL. Since it is wrappedround the unshielded flange connec-tion, the flange dimensions are requiredon order. With the N-connector it canbe directly jointed with a UHF pream-plifier like the UHF1, UHF2 or RPA6C.

AS75ISFX2/50SFX1

Ultrasonic PD SensorsThe AS75I and AS150I are active sensors with very high sensitivity for measure-ments on GIS, transformer tanks, or cable joints. They come with a built-in 40 dBpreamplifier and can be connected to the RPA1D, RPA1F, RPA1G or directly tothe AIAcompact, ICMsystem, ICMcompact or ICMmonitor.

The SFX1 is suited to secure the acoustis sensors on a GIS.The magnetic sen-sor fixtures SFX2 are for temporarily mounting of the acoustic sensors on a trans-former tank.

Acce

ssor

ies

- Sen

sors

& M

isce

llane

ous

PD •





AB1

AB1 Active Bridge AdapterThe active bridge adapter is an op-tional accessory that can be used incertain circumstances to “subtract”noise from the measurement setup.

The active bridge adapter AB1 servesto balance the signal picked up by twopreamplifiers to reduce the commonmode noise or disturbance. Thismethod is applicable when twobranches are available.

A mismatch of the signal strength canbe adjusted with the AB1‘s controlknob. With the preamplifiers of the twobranches connected to the “Pos” and“Neg” input of the AB1, and the out-put connected to the AMP IN of thePD detector, the control knob is usedto minimize the common mode signal.

CTB1 Coupler Termination BoxThe CTB1 provides protective ground-ing of the cabling comming from thecoupling capacitors. An over voltageprotection of the signal path is in-cluded and ensures safe working onlive test specimen.CTB1

Foil sensor DFS

DFS Differential Foil SensorBesides the embedded coaxial sen-sor of cable accessories, external sen-sors can be applied to joints and ter-minations. Especially on cross-bond-ing joints differential foil sensors serveto capture partial discharge signals inelevated frequencies. Such foil sen-sors can be permanently installed formonitoring or temporary applied forsurvey type measurements.

CSC1

IPU1

IPU4

IPU2

CSC1 Signal CombinerThe CSC1 allows to select or com-bine signals from 4 BNC-inputs to oneBNC-output. The input and output im-pedance is thereby kept to 50Ω, evenif one channel is selected or if thesum of all four channels is selected.

IPU1, IPU2 Input Protection UnitThe protection units are designed toavoid damage of spectrum analyzerinput circuits or of preamplifier inputstages under the presence of strongtransient signals.

PD •

47


Acc

esso

ries

CT1 fixed current transformer

The CTs are a low-impact PD sensor option since no interruption of thepower connection is required. Such installation is even possible under on-line conditions, as the CT100 is a clamp-on current transformer that canbe opened and clamped around a connecting cable, a ground lead, oreven a feeding medium-voltage cable with a high-voltage motor in-stallation.

ICMseries Accessories:Sensors and Miscellaneous

Current TransformersWhen a current transformer is used instead of a quadrupole, the current trans-former can be placed around a coupling capacitor terminal or around a part ofthe test object itself. A current transformer has the advantage of providing gal-vanic isolation between the ICMseries PD detector and the high voltage circuit.Power Diagnostix offers current transformers as separate modules or integratedwith a coupling capacitor into a single unit.

CT100 clamp-on current transformer

The disturbance antenna DA1 can be used to pick up noise sig-nals caused by local corona discharge, or AM radio waves forinstance. It's magnetic holder allows a flexible placement on atransformer tank or to other metallic parts close to the objectunder test. The ouput signal can be used to trigger the gateinput circuit of all PD acquisition or monitoring devices. DA1

disturbance antenna

Acce

ssor

ies

- Sen

sors

& M

isce

llane

ous

Type Transfer ratio at 50 Ω Primary window Bandwidth at -3 dB Bandwidth at -6 dBCT1 1 : 10 15 mm 0.5 - 80 MHz 0.3 - 100 MHzCT100 1 : 10 100 mm 2 - 25 MHz 1.2 - 40 MHz

PD •




48

The versatility of the Power Diagnostix line of PD detection equipment is duein large part to the range of accessories available for the ICMseries instru-ments. Each ICMseries data acquisition unit can be combined with differentaccessories to suit specific applications. Power Diagnostix 2010

BCU Bushing Coupler UnitThe Bushing Coupler Units are for per-manent installation on power trans-formers. Together with a matching

bushing adapter they serve to makedifferent signals available for measure-ment and monitoring. The bandwidthof the partial discharge signals extendsto 20 MHz. The voltage signal of thebuilt-in capacitive divider serves to syn-chronize the partial discharge acqui-sition and to measure the voltage.However, the excellent bandwidth ofthe voltage signal allows also transferimpedance measurements and tanδ(power factor) measurements.

Transportation Case for theICMseries InstrumentsAll instruments of the ICMseries canbe delivered with a solid transportcase with cut-out foam to carry oneinstrument and its accessories.

BCU1D

BA Bushing Adapter

Width Hight Depth Weight(empty)

Large 65 cm 27 cm 46 cm 7,5 kgSmall 49 cm 22 cm 38 cm 5,1 kg

Type Thread Size Conne ction Size Suitable forB A2 ins ide G4/4 fe m a le 4 m m Mica fi l, POR IBB A3 ou ts ide M45x2 fe m a le 8 m mB A4a dap te r

flangeins ide

--M76x1 .5 m a le 8 m m

B A5 ins ide M24 m a le 4 m m H S P, ESK TFK 10 50 /245 -AB A6 ou ts ide M38x1 .5 m a le 4 m m Mica fi l, W TF 420 /1800 (1978)B A7 ou ts ide 2¼" - 1 2U N F fe m a le 8 m m Pcore , C S A s tandard , POCB A8 ins ide 5 /8 " - 1 1U N C -- 3 m m ABB , GOBB A9 ou ts ide M30x1 .5 fe m a le 4 m m H S PB A10 ou ts ide M16x1 .5 fe m a le 4 m m Trench , C OT 650 -2500B A11 flange -- fe m a le 8 m m GOA 650 / GOA 105 0B A12 ou ts ide M30x2 fe m a le 6 m m N GK, R -D 53 50D -KEWB A14 ou ts ide 1 1 /16 " - 12U N fe m a le 8 m m TTIB A15 ou ts ide M30x2 fe m a le 9 m m N GK, R -C 62 00V-LNB A17 ou ts ide M30x2 fe m a le 4 m m ABB , GOB 1050-750 -1100-0 ,6 -BB A18 flange -- fe m a le 8 m m Mos izo lya to r, GMTA-90 -110 /200 0B A19 flange -- fe m a le 8 m m Mos izo lya to r, GMTA-45 -330 /250 0B A20 ou ts ide 2¼" - 1 2U N F fe m a le 8 m m Trench

PD •

49


Acc

esso

ries

ICMseries Accessories:Calibrators

CAL1A

Conformity to International StandardsBy end of 2003, Power Diagnostix received the accredita-tion as calibration laboratory within the German Calibra-tion Service (Deutscher Kalibrierdienst, DKD). The auditwas held by 'Physikalisch Technische Bundesanstalt' PTB,the German authority of standards. Power Diagnostix ac-creditation is filed under DKD-K-31101.

New charge calibrators are shipped with the DKD calibra-tion certificate to ensure the traceability to internationalstandards. However, Power Diagnostix still offers the cost-effective factory calibration, if the formal traceability is notrequired.

Simple to UseThe calibrator is switched on with the pushbutton On/Off.Both amplitude (Range) and polarity (Pos/Neg) of thesingle charge pulse per cycle are displayed and can beadjusted by pressing of the two buttons. Each calibrator isalso available supplying two pulses per cycle, as well aswith double impulse output with adjustable interval.

The instrument automatically synchronizes to line frequencyby a photo diode. In case of insufficient pick-up of powerfrequency light, the calibrator automatically selects the in-ternal quartz oscillator (50Hz- and 60Hz-versions available).

Power Diagnostix makes a range of calibration charge injectors suitable for usein calibrating partial discharge measurements. The appropriate choice of acalibration instrument depends on the range of typical charge values of the PDsbeing measured. Calibrators can also be used for time domain reflectometry incables to determine cable length and location of joints.

Acce

ssor

ies

- Cal

ibra

tors

PD •





CAL1B

Available CalibratorsThe standard calibration impulse generator CAL1A offers thecharge range of 1/2/5/10/20/50/100 pC, while the CAL1B, mainlysuitable for rotating machine testing, covers the range of 100/200/500pC/1/2/5/10nC.Special signal sources are available for GIS measurements, suchas the CAL2A: 0.5/1/2/5/10/20/50 pC, tR ≤ 300ps, f3dB ≥ 1 GHz, orwith voltage output, the CAL2B: 0.5/1/2/5/10/20/50 V, ZL=50 Ω,tR ≤ 200ps, tF = 100 ns.The Power Diagnostix line of calibration impulse generators isunique in that the charge pulse is generated by injecting a vari-able voltage step (correlated to an internal reference) via a fixedcapacitor. This injection capacitor is relatively small, as the stepvoltage amounts up to 120 V for full range output. Therefore, thePower Diagnostix calibrators offer excellent impulse properties.Further, calculation of the correction factor is usually not neces-sary (CI<<CS).The standard line of Power Diagnostix calibration instruments islisted in the table below, along with their ranges and key features.

Cal

ibra

tion

Impu

lse

Gen

erat

or

Ran

ge

Inje

ctio

n C

apac

itor (

CI)

50H

z or

60H

z lig

ht s

ync.

IEC

6027

0 co

mpl

iant

2 pu

lses

/ cy

cle

optio

nBN

C c

onne

ctio

n

Usa

ge

CAL1A 1, 2, 5, 10, 20, 50, 100pC <1pF standard, lab useCAL1B 100, 200, 500pC, 1, 2, 5, 10nC <100pF see CAL1E & FCAL1C 1, 2, 5, 10, 20, 50, 100pC* at 100pF V (50Ω) c/w ext. capacitorCAL1D 10, 20, 50, 100, 200, 500, 1000pC <10pF standard, lab useCAL1E 0.5, 1, 2, 5, 10, 20, 50nC <500pF

CAL1F 0.2, 0.5, 1, 2, 5, 10, 20nC <200pF

high level application, e.g. rotatingmachines, cable field tests

CAL1G 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2nC <20pF transformer testCAL1H 0.5, 1, 2, 5, 10, 20, 50pC* at 2pF V (50Ω) GIS, live injection via stray cap.

CAL2A 0.5, 1, 2, 5, 10, 20, 50pC <1pF - N GIS & UHFCAL2B 0.5, 1, 2, 5, 10, 20, 50V (into 50Ω) V (50Ω) -

---

N GIS & UHF

CAL2C 0.2, 0.5, 1, 2, 5, 10, 20V (into 50Ω) V (50Ω) --

--

N GIS & UHF

CAL3A 700kHz to 1.35MHz, 10µV to 10mV V (50Ω) RIV calibration

CAL3B 400kHz to 1.9MHz, 10µV to 10mV V (50Ω) RIV calibration*with external high voltage capacitor

PD •

51


Ap

plic

atio

ns

Applications - Transformer

Partial discharge measurements on power and distribution class transformer area proven tool to identify and locate defects within the insulation system of bush-ings, windings, or accessories. Besides PD acceptance test equipment for thetesting labs in a factory Power Diagnostix offers a wide range of instruments foron-site on- and offline tests, and for monitoring.

The ICMsys8 greatly simplifies the PDacceptance tests on large power trans-former. With its true parallel acquisitionof the PD activity on eight channels, theoverall testing period is substantiallyshortened. E.g. the cross coupling ma-trix for the different phases is done au-tomatically while calibrating the testsetup.

An advanced PD analysis system con-sists of an ICMsystem for PD patternacquisition, a built-in or external spec-trum analyzer for frequency domainanalysis, a standard oscilloscope for theevaluation of the time domain signals,and an acoustic measurement systemincl. triangulation software. TheICMspectrum software was developedto simplify the use of an external spec-trum analyzer in conjunction with thePD measurement. Critical frequenciescan easily be detected and filters canbe set for in-depth analysis. The

110/220 kV transformer, RWE, Germany

ICMacoustic software, analysis panel

ICMsys8

Remote SW with HP spectrum analyzer

ICMacoustic software provides graphi-cal and mathematical evaluation toolsto precisely locate internal PD failures. A

pplic

atio

ns -

Tran

sfor

mer

s

PD •




52

Bushing adapter

Transformermonitoring

HV control room

ICMcompact with multiplexer

In addition to the noise supressionfunctions of the instruments, PowerDiagnostix offers a wide range of highvoltage filters for induced or appliedvoltage testing.

PD MonitoringPartial Discharge Monitoring has be-come increasingly important in thepast few years. Besides other param-eters like gas in oil analysis, tempera-tures, vibrations, or load conditions,etc., the PD trending information com-pletes a full set of monitoring data ofa transformer in the field. A series ofstandard bushing adapter (BA) isavailable to connect the measure-ment system to the test tap of a trans-former bushing. For condition basedmaintenance, a portable instrumentlike the ICMsystem can be used on-site for temporary measurements. Forcontinuous monitoring, an instrumentsuch as the SPECmonitor or the

Partial discharge testing on power transformer is an efficient tool to evalu-ate the condition of the complex insulation system. Power Diagnostix offersvarious optimized instruments and accessories for laboratory tests, fieldmeasurements, and continuous monitoring.

SPECcompact

Typical PackagesSet for Power transformer accep-tance testing in a test bay:- 1 x ICMsys8 (built-in modem opt.)- 1 x GPIB interface- 1 x Software ICMsystem- 1 x Impulse calibrator CAL1D- 9 x Preamplifier RPA1- 8 x Quadrupole CIL4M/V0µ5/2µ0- 3 x Quadrupole CIL5M/V4µ0

Set for distribution transformerAcceptance testing in a test bay:- 1 x ICMsys4 or ICMcompact/MUX4- 1 x GPIB Interface (with ICMsys4)- 1 x Software ICMsystem- 1 x Impulse Calibrator CAL1D- 4 x Preamplifier RPA1- 3 x Coupling Capacitor CC100B/V

Optional items:- RIV measurement- Built in spectrum analyzer- Scope with remote control software- Acoustic Sensors and Preamplifier- CT1 or CT100 for gating purposes- HV Filter- External spectrum analyzer

The SPECcompact comprises a spec-trum analyzer and a partial dischargedetector in one instrument. This allowsPD measurements even in noisy en-vironments like non-shielded test ar-eas. Especially for testing distributionclass transformer the SPECcompactallows measurements with a back-ground noise below the demandedacceptance level.

ICMmonitor can be considered.Acoustic sensors in combination withone of the mentioned PD instrumentscan be used to locate a PD fault moreprecisely.

AdvancedPD test system

PD •

53


Ap

plic

atio

ns

Applications -Rotating Machines

The typical epoxy-mica insulation system of rotating machines is a 'forgiving',i. e. a comparably stable insulation system. Due to this electrical stability, partialdischarge activity acts as an indicator for a variety of defect mechanisms. Be-sides the mere electrical aging, further problems, such as contamination, vibra-tion, or mechanical aging find their expression in the phase-resolved partial dis-charge pattern.

PD activity acquired with the ICMsystemshowing the non-symmetrical dischargepattern of a heavily deteriorated slot-exitfield grading.

Permanently installed partial dischargecouplers greatly simplify on-line testing

PD MeasurementsPower Diagnostix offers various instru-ments for continuous monitoring, sched-ule-based routine testing and in-depthanalysis of rotating machines. The in-struments and their control softwarewere continuously improved, based onmore than ten years of testing numer-ous generators and motors.

using the ICMsystem without any inter-ruption or downtime. Continuous on-line monitoring of the discharge activ-ity with a permanently installedICMmonitor helps optimizing mainte-nance intervals and reducing costs,while improving the level of equipmentdependability.

Tan Delta MeasurementsThe TDAcompact is a digital tan deltaand power factor analyzer for off-linedielectric testing to assess the overallhealth of the insulation system. Its fi-ber optic signal transmission simplifiesconnection even on grounded equip-ment. The unit comes with referencecapacitor and can be combined withany external high voltage source.

TDAcompact App

licat

ions

- R

otat

ing

Mac

hine

s

PD •




54

ICMmonitor on-site

Stator coil

Coupling units CC20

ICMmonitor display

Typical PackagesPortable acquisition unit:- 1x ICMsystem (opt. MUX8)- 1x ICMsystem software- 1x GPIB interface- 2x Preamplifier RPA1- 1x Preamplifier RPA2- 1x Voltage converter HST1B- 1x CT1 or CT100 (optional)- 1x Impulse calibrator CAL1B- Set of cables- Transport case

List of material per machine:- 3x Coupling capacitors, type CC14B or CC20B- 1x Mounting kit, MKB

Partial Discharge MonitoringBased on the stand-alone ICMmonitorunit connected to an individual ma-chine, larger networks supervising amultitude of generators in combined-cycle thermal power plants or pump-storage hydro power plants havebeen realized. Such networks includefull control of the local instrument viaglobal Intranet access as well as vi-sualization of the monitoring data inmonitoring centers. The ICMmonitorsoftware offers automated scanning,pattern acquisition, and analysis ofthe trending data. Additionally, theICMpilot software serves to condensethe information gathered from mul-tiple plants on one overview screen,while having the full data history closeat hand.Large MotorsHigh voltage motors are key-compo-nents in refineries and the productionof technical gasses according to theLinde process. Here, unplanned out-ages can cause immense losses. Fur-ther, such motors serve in thermal andnuclear power plants to run the (emer-

CT100

Couplers CC14B installed on a motorterminal box

ICMmonitor trending display

gency) cooling system, for example.Here, failure of a motor stator wind-ing can cause critical subsequentdamage. Installing specially suitedcoupling capacitors offers schedule-based measurements as well as con-tinuous monitoring for the assess-ment of the insulation condition.

Partial discharge testing and monitoring on generators and large motors of-fers the assessment of the condition of the stator winding. This helps avoid-ing unplanned outages as well as scheduling efficient maintenance outages.

PD •

55


Ap

plic

atio

ns

Applications - GIS / GIL

Besides factory partial discharge testing for quality assurance, field-testing be-comes increasingly important for gas-insulated equipment. For the field applica-tions UHF and acoustic detection methods complement the low frequency de-tection according to the IEC60270.

ATTanalyzerThe portable ATTanalyzer is a simpleand very effective tool to locate break-down during the commissioning of GISand GIL. Battery-operated acousticsensors are externally mounted to theGIS and connected via fiber optic cableto the acquisition unit. In case of break-down, the acoustic sensor transmits anoptical signal to the ATTanalyzer, whenit has detected the sound wave. TheATTanalyzer then displays the signalsreceived from all sensors versus timelike a logic analyzer. Following initial lo-cation of the breakdown’s origin, theacoustic sensors can be repositionedcloser to the flaw to further narrow downthe location.

ICMcompactThe ICMcompact combines perfectlywith small tank-type variable frequencytest sets for the commissioning testingof gas-insulated substation equipment.Besides the flexible analog gating func-tion, the ICMcompact comes with a TTLgating input to effectively suppress theswitching impulses of the resonant testset.

AIAcompactThe main application of the AIAcompactis the acoustical detection of partial dis-charge in gas-insulated equipment. Con-veniently, the unit provides the supplyvoltage of the different pre-amplifiers andthe acoustic sensors. The instrument islightweight and battery operated. More-over, the AIAcompact allows conductingUHF measurements when connected toembedded or external UHF sensors. TheAIAcompact automatically detects thepre-amplifier type and selects the appro-priate operation mode.

For in-depth field analysis of partial dis-charge activity the ICMsystem can becombined with a spectrum analyzer.Power Diagnostix has written the spe-cial software ICMspectrum to utilize andcontrol spectrum analyzers of differentvendors for partial discharge analysis(HP 859xE, Agilent E4000, R&S FSL).

Field measurement set up

ATTanalyzer

App

licat

ions

- G

IS /

GIL

PD •




56

Breakdown sensor

Preamplifier RPA6C

GIS window sensor

Ring sensor on GIS

Partial Discharge MonitoringThe same sensors (external or inter-nal) as used for commissioning canbe used for continuous on-line moni-toring of the partial discharge activity.Here, acquisition units equipped withbuilt-in multiplexer scan the numberof sensors, each directly connectedto a small preprocessing amplifier unit(RPA6C). This preprocessing unit actsas a detector and converts the ultra-wide bandwidth signal into a low-fre-quency envelope signal, which is thenconveniently transmitted via regularRG58 cable. The RG58 cable alsoprovides the DC supply for the pream-plifiers. Embedded modem units orTCP/IP interfaces offer remote accessto a multitude of monitoring units viathe Internet, an Intranet, or the tele-phone network.

Monitoring system

Typical Packages

Instruments for commissioning andservice groups:

- AIAcompact- ATTanalyzer- ICMsystem with spectrum analyzer or ICMcompact- UHF preamplifier- External retrofit UHF sensors- Acoustic sensors- UHF calibrator CAL2B

UHF impulse calibrator CAL2B

Power Diagnostix range of instruments cover the entire needs of partial dis-charge testing on gas-insulated substation equipment from production test-ing and commissioning to maintenance and monitoring.

Example for a PD monitoring systemon a 123 kV substation:

- 1 x Portable ICMmonitor, or 10 x ICMmonitor for permanent installation, 8 channel multiplexed;- Option: built-in modem or TCP/IP- 1 x Software ICMmonitor (GIS vers.)- 1 x Remote computer- 1 x Impulse calibrator CAL2B- 80 x retrofit ring or window sensors- 80 x preamplifier RPA6C- 80 x Set of cables

Accoustic sensor

PD •

57


Ap

plic

atio

ns

Applications - Cables

Extra High Voltage (EHV) CablesCables are generally factory-tested. Theaccessories of high voltage (HV) andextra high voltage (EHV) cables are usu-ally also pre-tested. However, mechani-cal forces during the laying, hidden im-perfections, and flaws caused by im-proper handling, for instance, requirepartial discharge commissioning tests.Ideally, the cable accessories of suchtransmission-class cables are equippedwith embedded sensors. Power Diag-nostix introduced this cost-effective prin-ciple in 1994 and numerous cablemanufacturers have implemented itsince then. The ICMsystem, especiallyif enhanced with the FOsystem for opti-cal isolation, offers powerful tools for the

Polyethylene is a ‘non-forgiving’ insulation system. Thus, close attention must bepaid to partial discharge activity during factory testing, commissioning, and ser-vice. On-site measurement techniques have to cover the needs of an aging poly-meric cable distribution net as well as an increasing application of polyethyleneextra high voltage cables.

analysis of the cable insulation system.Additionally, different pre-amplifiers andembedded or external spectrum analyz-ers complete the instrumentation.

ICMsystem

Medium Voltage CablesAs with HV and EHV cables, theICMcompact is used for shop-floor pro-duction testing on medium voltagecables. During the past decade numer-ous cable manufacturers have changedto this instrument during the modern-ization of their test room.

A large population of service-aged me-dium voltage or distribution-classcables has reached their projected ser-vice live, as polymeric cables were in-creasingly introduced since the1970ies. The ICMcompact is availablein a ready-to-use package for field test-ing and partial discharge location withany external high voltage source. Es-pecially the combination with very lowfrequency (VLF) sources and the com-bination with variable frequency reso-nant test sets provide lightweight andcost-effective solutions to keep the dis-tribution grid reliable. The package in-cludes a combination of T-filter andcoupling unit to de-noise the HV source.

PD fault location display

App

licat

ions

- C

able

s

PD •




58

Cable monitoring

400 kV cable joints

CT100 & RPA1

DFS for cable joints

Cable PD sensor

Special SensorsCoupling capacitors, as used for fac-tory testing and for off-line testing, arenot applicable for on-line testing.Power Diagnostix offers several typesof external sensors for PD measure-ments. The differential foil sensor(DFS) makes use of the stray capaci-tance of cross-bonding joints and of-fers comparable low-noise measure-ments at higher frequencies. TheCT100 is a clamp-on HF current trans-former that can be used to pick uppartial discharge signals on groundleads and on cross-bonding connec-tions. Further sensors includingRogowski coils can be tailor-made forany application. Power Diagnostixalso assist with the design and imple-mentation of embedded sensors.

Monitoring system in a cable tunnel withWLAN interconnection

Combining the lightweight ICMcompact for partial discharge location withportable VLF high voltage sources or variable frequency resonant test setsoffers cost-effective survey testing of a distribution grid.

PD MonitoringGenerally, partial discharge monitor-ing can take care of any high voltageinsulation system to detect incipientbreakdown and on-going degrada-tion. The defect mechanisms for cableaccessories and for the cable itself dif-fer due to different material proper-ties, for example. When monitoring

EHV cables systems, a comparablelong pre-warning time applies to EPRand EPDM accessories, while thecable insulation of a 400 kV XLPEcable, for instance, has a muchshorter pre-warning time.

Further, an installed monitoring sys-tem can be used of course also forthe commissioning testing of thecable system. Besides using fiberoptic TCP/IP interconnection, access-ing the instruments via WLAN offersan effortless installation.

Typical PackagesMobile PD fault location systemconsisting of:

- 1x Portable ICMcompact with built-in DSO board- 1x Software ICMcompact with fault PD fault location- 1x Coupling capacitor CC25D/V- 1x Impulse calibrator CAL1B- 1x Preamplifier RPA1H- 1x Preamplifier RPA1- 1x Set of cables

S

Silicone

XLPE Insulation

Stress-ConeSensor Layer

Screen

Signal Cable

Conductor

J 4J 3J 2J 1J 4J 3J 2J 1

J 4J 3J 2J 1

ICMcompact PD fault location software

PD •

59


Ap

plic

atio

ns

Applications - Quality Control

Modular ConceptDifferent levels of automation can beprovided depending on the testingneeds. In case of full production test-ing a high level of automation andsimple go/no go decision is needed,

Partial discharge testing – well established for high voltage equipment – be-comes increasingly important for insulation systems of a lower voltage level.Changing to switching power supply and to IGBT control of induction motors, forinstance, raise demands and testing needs for the insulation system. The modu-lar concept of Power Diagnostix’ instruments allows offering customized solu-tions for automated and semi-automated testing.

voltage transformer and instruments tocontrol and measure voltage and par-tial discharge. The setup includes thesafety interlock, automated groundingsystem, and over-current protection.Different levels of automation are of-fered combining the HVcontrol, thebasic HVcompact for voltage measure-ment or the STEPcompact for program-ming voltage steps, ramps or morecomplex functions. Installed on an in-dustrial PC, the HVpilot software thenoptionally controls these instrumentsand the ICMcompact for the PD signaland automatically prepares the test re-port. Additionally, Power Diagnostixdesigns special test fixtures, dual testchambers for increased performance,and customer specific software.Alternatively, of course, such instru-ments can be used to modernize thecontrol of an older high voltage trans-former and its regulating transformer.

Partial discharge test cabinet for stator coils of small induction motors

whereas manual control offers a higherlevel of flexibility when testing samplesor sample variants during development.Generally, such test arrangement con-sist of a test chamber with a built-in high A

pplic

atio

ns -

Qua

lity

Con

trol

PD •




60

Control andmeasurement

HV test room

Levels of AutomationDepending on the needs the instru-ments and controls can be compiledin different versions:

Level A:Partial discharge test bench forsample testing consisting of a testchamber and manual voltage controlequipped with an ICMcompact for PDmeasurement with voltage option oran HVcompact for voltage measure-ment.

Level B:As level A, but with the STEPcompactinstead of the HVcompact for auto-mated voltage control.

Level C:As above, but with an industrial PCand the HVpilot software for fully au-tomated control and test report gen-eration.

Level D:Modernization of test rooms usingHVcontrol, HVcompact orSTEPcompact, and ICMcompact.Software control as with level C.

Partial discharge testing is increasingly applied for testing insulation sys-tems of lower voltage levels. Power Diagnostix offers ready-to-use test cham-bers for easy and safe partial discharge testing on components and smallsamples.

Typical PackagesTest setup (like level C)consisting of:

- 1 x ICMcompact with gating- 1 x STEPcompact, 19’’ rack- 1 x Test chamber 19’’, 18HU,

incl. 10 kV voltage transformer, regulator, manual control buttons, horn, lamps, emergency stop, grounding sys tem, coupling capacitor, ...

- 1 x Indusrial PC- 1 x Software ICMcompact- 1 x Impulse calibrator CAL1A- 1 x Preamplifier RPA1- 1 x Set of cables

Type Voltage Power Current Connection Height Dimension WxHxD

TCU 3 0-230V 3kVA 16Amax CEE 400/16A (L-N) 9HU 553 x 506 x 600 mm

TCU 7,5 0-230V 7,5kVA 34Amax CEE 400/32A (L-N) 9HU 553 x 506 x 600 mm

TCU 10 0-230V 10kVA 48Amax CEE 400/63A (L-N) 9HU 553 x 506 x 600 mm

TCU 10/2 0-400V 10kVA 25Amax CEE 400/63A (L1-L2) 9HU 553 x 506 x 600 mm

TCU 15/2 0-400V 15kVA 38Amax CEE 400/63A (L1-L2) 25HU 553 x 1218 x 600 mm

Typical test set

TCU7,5

PD •

61


Ser

vice

s

Services

ConsultingPower Diagnostix assists to analyzeencountered defects, failuremechanism, and helps to improveinsulation systems. Further, support isprovided to implement monitoringsystems and to integrate embeddedpartial discharge sensors into insulationsystems. Additionally, Power Diagnostixoffers interpretation service for partialdischarge pattern acquired by localtesting groups. Instruments equippedwith modem allow also having PowerDiagnostix dialing in for performingremote measurements and diagnosis.

Power Diagnostix provides various services such as on-site measurements, com-missioning tests, DKD calibration of instruments, installation of couplers and moni-toring systems, as well as rental of test equipment. Additionally, Power Diagnostixacts as a consultant to analyze defect mechanism or to improve high voltageinsulation systems, for instance.

Measurement in a transformer test bay

On-site measurements

Seminar held in Aachen 2006

On-site MeasurementsPower Diagnostix engineers are avail-able on short notice for on-site partial

discharge measurements. Such on-sitemeasurements cover on-line and off-line diagnostics on rotating machinesincluding large motors, partial dischargemapping on cable systems, survey-typemeasurements on gas-insulated sub-station equipment, and partial dis-charge acceptance testing and PD lo-cation on large transmission-classpower transformers. All required instru-ments are provided, of course. VLFsources and smaller high voltagesources can be provided as well. How-ever, rental of larger test sets needs tobe subcontracted.

Seminars and TrainingStandard shop-floor partial dischargetesting is a comparable easy task. How

Ser

vice

s

PD •




62

DKD-calibration

Factory-calibration

Installing couplers on site

Accrediation certificate

Power Diagnostix offers in-depth support including on-site testing and installa-tion services as well as consulting on partial discharge issues. Training sessionsand seminars are offered at Power Diagnostix factory in Aachen or on-site. TheDKD calibration of instruments and calibrators is offered at a competitive price.

Installation ServiceEspecially for monitoring systems acomplete installation service is offered.Typically, this installation of couplersand instruments include the calibrationof the entire setup and the base-linemeasurement.

Rental of EquipmentGenerally, Power Diagnostix testingequipment is available for rental orleasing, if budget constraints do notallow an investment, for instance.

DKD Calibration ServicePower Diagnostix operates a calibra-tion laboratory, which has received theaccreditation within the German Cali-bration Service DKD by 2003. The au-

dit was held by ‘Physikalisch Tech-nische Bundesanstalt’ (PTB), theGerman authority of standards.Power Diagnostix’ accreditation isfiled under DKD-K-31101. The ac-creditation covers impulse charge(pC), voltages, and timing param-eters. Since 2006 the accreditationincludes also on-site calibration ofvoltages up to 100 kVAC.

The DKD calibration service is ofcourse also available for instrumentsand calibrator of other vendors. How-ever, the cost-effective factory cali-bration applies only to instruments ofPower Diagnostix make, if the fulltraceability of the DKD calibration isnot needed.

ever, applying in-depth partial dischargediagnostics requires knowledge and ex-perience. Here, Power Diagnostix as-sists with training sessions for testingand engineering personnel and withseminars for larger service groups. Be-sides the mere installation and usageof the instruments, emphasis is put onunderstanding the theoretical back-ground of partial discharge pattern, de-fect mechanism, and the interpretationof measurement results.

PD •

63




PD

Pat

tern

New motor coilStrong surface discharge at the overhangRemainder of void discharges

Single generator barPositive surface discharges for negativehalfcycle in the coupling branch

Large turbine generatorSignal coupling on the neutral sideDominant activities for one phase

New motor coilSeveral large voids

Small gas turbine generatorLine side coupling on one phaseModulated PD pattern (33rd harmonic)

Asphalt-mica insulated hydrogeneratorSignal coupling on the neutral sideActivities for all three phases

Typical PD Pattern

PD •



64 Power Diagnostix 2008

Power transformer (on-line)Signal coupling at the bushing tapCorona and internal discharge

Transformer bushingContact problem of the field control layers

Transformer modelPoint-plane assembly under oil

Surface dischargeMeasurement versus time

Transformer bushingCorona discharge due to heavy rain

Voltage transformerVoid and surface discharge with a distortedvoltage modulating the pattern

Typical PD Pattern

PD •

65




PD

Pat

tern

GIS instrument transformerExcitation from the low voltage sideInfluence of core saturation on the pattern

Gas-insulated switchgearSuperimposal of different PD pattern

GIS isolator modelSpherical void

Gas-insulated switchgearSeveral voids in a support insulator disc

Gas-insulated switchgearTwo hopping particles of different size andfrequency of occurrence

Gas-insulated switchgearHopping particle

Typical PD Pattern

PD •



66 Power Diagnostix 2008

Cable jointInternal discharges in a prefabricated EPR joint

Cable jointDischarges in a wrapped XLPE jointMeasured at 10MHz

Laboratory setupSmall voids in the insulation at the interfaceto a semi-conductive layer

Cable jointDelamination of the outer semi-conductivelayer of a prefabricated EPR joint

Cable terminationContact problem of the field control of awrapped termination (mass impregnated)

Cable terminationSeveral flat cavities in silicon fat due toimproper mounting procedure

Typical PD Pattern

PD • Location

E40: Brussels

A44: DüsseldorfA4: Heerlen

Direction Klinikum

Lütticher Straße

Luxemburger Ring

Pariser Ring

Exit Laurensberg

A4: Cologne

Rev. 8.30

Exit Aachen Süd

Vaalser Straße 250

Eupener Straße

PD •

Email: [email protected]

www.pdix.com

Power Diagnostix ⋅ Vaalser Strasse 250 ⋅ 52074 Aachen ⋅ Tel +49 241 74927 ⋅ FAX +49 241 79521

Brochure2010 en l

Documents

Transcript of Brochure2010 en l