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sustainable solutions. for a better life.

www.diatechsystems.com

 VA TECH HYDRO

Smart Module to assess surface partialdischarge of windingsconsisting of:

Control-, acquisition- and diagnosis softwareCooling air sample measurement systemOzone analyzer

damage in the stator winding area. PD

produces ozone and its concentration can be

measured by taking air samples from the

generator cooling air circuit.

The advantage of this method is:● the simplicity of the installation (only

hoses are to be installed)● the simplicity of retrofitting at existing units● the dielectric monitoring of the entire

winding system with one single

measuring-point.

DIA TECH CAA-O3 – COOLING AIR ANALYSIS – OZONE DIAGNOSIS

 The Cooling Air Analysis module (CAA)

consists of two independent sub-modules,

the “hotspot-detection” (HS) and the

“ozone diagnosis” (O3). Both modules are

based on similar measurement methods: air

samples are taken from the generator coolingair circuit allowing measurement of the con-

centration of certain gas contents or of ozone,

which are emitted from various insulating

materials under certain conditions. The air

samples are transferred through Teflon®

hoses to suitable analyzers, which determine

the concentration of the particular gas.

 The results are transmitted to the DIA TECH

system for further diagnostic processing.

One single hose per generator and per

module (HS/O3) is sufficient. At least onemore hose is necessary to measure the

ambient conditions in the power house for

reference.

DIA TECH CAA-O3

makes assessment of insulation condition by

analyzing its surface partial discharge (PD)

activity. Surface PD informs about dirt,

changes of potential gradients, and insulation

Scheme of Cooling Air Analysis

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machine hall, under consideration of stator

current, stator voltage and air humidity.

 Air humidity influences the PD activity

immensely and is therefore a main parameter

for assessment of insulation condition.

Diagnosis limit values are to be defined after

a certain period of continuous data

acquisition. An individual “finger print” of each

unit is made. In case of failure detection

the system generates diagnosis messages.

DIA TECH CAA-O3 – COOLING

 AIR ANALYSIS – OZONE DIAGNOSIS

 VATECH HYDRO GmbH& Co

Penzinger Strasse 76,

P.O. Box 5

 A-1141 Wien

Phone (+43/1) 89 100-0

Fax (+43/1) 89 46 046

E-mail contact@vatech-hydro.com

 VA TECH HYDRO GmbH&Co

Service Centre Weiz

Monitoring & Diagnosis

Elingasse 3, A-8061 Weiz

Phone (+43/3172) 606 2296

Fax (+43/3172) 606 496

E-mail diatech@vatech-hydro.at

ispartof , the integratedcommon solution for secondary technology.

 left: ozone analyzer, middle: example of DIATECH Trend display, right: pneumatic MUX 

 Acquisition of measured values:

Required

hardware:

● Ozone analyzer● Elin MUX (pneumatic multiplexer)● Elin Datalogger (control

equipment with control program)● Humidity sensor

 Auxiliary parameters

for diagnosis

● Stator current + Stator voltage●  Air humidity

Main specs:

Measuring technology of ozone analyzer:Ultraviolet absorption

●  The system is limited to 8 measuring points:6 units and 2 references

● Measuring cycle: (dependent on hose length):10 to 15 minutes

● Hose dimension: outer/inner Ø: 6/4 mm

● Hose material: Teflon®

 The analyzer collects samples from points up to200 meter away.

Requirements:

DIA TECH CAA-O3 requires the data managementsoftware package DIA TECH CORE System.

 All DIA TECH Modules are running on standardpersonal computers with Windows XP.

Processing of measured values

 The maximum of measuring points is eight –

six for the units and two references. A

pneumatic multiplexer – the Elin MUX –,

which is controlled by the Elin Datalogger,

manages sequence of measuring cycles and

assignment of measured concentration

values. The Elin Datalogger transmits the

pre-processed data to the computer, wherethe diagnosis software analyses the con-

centration results considering load and

ambient conditions. The load condition is

represented by stator current respectively

stator voltage, which is obtained from the

existing instrumentation and control system.

Ozone concentrations, which are collected

from the individual generators, are compared

with the reference concentration of the

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