Over View of Line and Sub-Station Maintenance
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Transcript of Over View of Line and Sub-Station Maintenance
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WELCOME TO THE
OVERVIEW OF HOT-LINE
MAINTENANCE
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Details of Hot Line Sub-Divisions in
APTRANSCO
No. of Divisions are 2
No. of Sub-Divisions are 10
1. Hyd. Division1. Metro SD
Hyd. & RR
2. Hyd. SDMedak&Mahaboobnagar
3. Kurnool SD
Kurnool & Atp4. Kadapa SD
Kadapa & Chittor
5. Ramagundam SDKnr, Nzb & Adb
6. Seetarampatnam SDKhammam &Warangal
2. Vja. Division7. Vijayawada SD
Krishna & Guntur
8. Nellore SDPrakasam & Nellore
9. Vemagiri SDEast & WestGodavari
10. Vijag SDVijayanagaram,Srikakulam & Vijag
APGENCO has one Hotlinesub-division at VTPS,Vijayawada.
Discoms are also planning toestablish Hot Line wings.
Hot Line Divisions are Headed technically by
the Chief Engineer and the Superintending Engineer /
Power Systems / Vidyuth Soudha / Hyderabad and
administration wise by the respective
zonal head the Chief Engineer / TL&SS and
circle head the Superintending Engineer / TL&SS.
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Staff Pattern in Each Sub-Division and
Benefits to HL Staff
Staff PatternEach Sub-Division is headed by one Asst. Divisional Engineer.
Under ADE there are three Assistant Engineers / Additional AssistantEngineers and
O&M staff of Foreman Gr.-I, Foreman Gr.-II, Line Inspector,Lineman, Lineman (Driver), Asst. Lineman and Junior Lineman.
BenefitsAs on date all the staff is paid 50% extra pay on starting cadre basic.
Risk Insurance for Rs. 10 Lacks per person.
Once in a year Safety items like safety shoes, safety goggles and waterbottle.
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INTRODUCTIONThe product of Electric Power is very important commodity.
Its rate of growth of demand is very high and it is increasingday by day.
Its percentage of shortage in the existing system is also veryhigh.
It is a critical element of infrastructure for economic
development and for improving the quality of life.It plays a vital role in improving the National economy andproductivity.
To meet the demand, the Government has liberalized thecompany rules.
Hence many Government and Private sectors are comingforward to Generate, Transmit and Distribute the ElectricPower in bulk quantities from one region to another regionby installing Super Thermal Power Stations, Extra HighVoltage Transmission lines and Extra High Voltage Sub-Stations.
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Need for maintenance
These Electric Power Transmission Lines and Sub-Stations have to be maintained properly for
1. un-interrupted power supply
2. system stability
3. reliable power supply
4. quality of power supply5. avoiding the forced outages
For maintenance, there are some conventionalmethods which are periodical, preventive andbreakdown.
With reference to the Hot-Line maintenance, themaintenance methods can be classified as Cold LineMaintenance and Hot Line Maintenance.
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1. Cold Line Maintenance: (Cold Line meansdeenergided Line) In this case, maintenance work will becarried out under the conditions of no current and nopotential i.e. Deenergised line. Hence it is called as Cold
Line Maintenance. .
2. Hot Line Maintenance: (Hot Line means an energizedLine) In this case, maintenance work will be carried outon live potential with out breaking the line current i.e.
Energised line. Hence it is called as Hot-LineMaintenance.
With reference to Conventional Maintenancemethods, this maintenance method comes under the
preventive maintenance.
Types of Maintenance
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Advantages of Hot-Line
Maintenance
Number of breakdowns will be reduced.
Inconvenience to the consumers will be reduced.
Interruptions will be reduced. By
Maintaining High Availability & Low Outage Rate of Lines.Free from Failure of Insulators due to Flashovers / De-capping
Damage to the equipment will be avoided and in-turnSaves the cost of the equipment.
Power system becomes more stable which otherwisemay become unstable due to failure of equipment.
with the above advantages, the Hot LineMaintenance on Transmission / Distribution lines andSub-Stations has been introduced.
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In Hot Line Maintenance the methods being used are
called as Live Line Maintenance Techniques (LLMT).
This type of maintenance works will be carried out by
observing the field & atmospheric conditions. Trained personscan only decide whether the conditions permit to work or not.
The work will be carried out by using right method and right
tool. If there is ambiguity either in technical feasibility of
work or suitability of atmospheric conditions, the work willnot be taken-up immediately. It will be postponed or informed
to the cold line wing to take-up the work in cold line in case
of emergency.
Before going to Live Line Maintenance Techniques, it
is better to discuss a brief history and development of Tools.
HOT LINE MAINTENANCE
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History & Development
1913 Ohio : First hot line tools were made with Woodensticks which were crude, bulky and difficult to handle.
1916-Atlanta : Wooden tools for some more Hot-Line works
were developed.1918-Tips tools company : Began manufacturing hot line
tools like wire tongs, tree trimmers, saddles, handtools and universal tools.
1937- Tips Tools Co. purchased by M/s. A.B. Chance Co.,
1940- With improved tools and safety, hot line maintenanceworks carried out up to 110 kv level.
1948- Mr. O.G. Anderson and Mr. N.R.Parkinson of
A.B.Chance carried out operation on 287 kv.
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History & Development
1950- Fibre Glass tools were introduced.
1954- Operation carried out on 330 kv with improved map-loccoated wooden tools.
1958 -Hot Line maintenance was introduced in India withestablishment of two Hot Line Training Centres (HLTC), one
at Bangalore and other at Ganguwal (Punjab) up to 110 kv.
1959 - A.B.Chance Epoxy glass came into existence.
1960 - Tools used on 400 kv and Bare Hand Method introduced.
1993 - Training inLLMT using Bare Hand Method on 400kvsystem was introduced.
2002 HLTC merged with National Power Training Institute.
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Hot line tools Features
Light in weight
Mechanically strong
High Dielectric strength
Ease in handling and installing
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Hot Line Tools
Wooden SticksIn the Beginning Hot Line Tools were
developed with Wooden sticks. They
have become obsolete because of theirown limitations and with the advent of
new technologies.
Hence now a days These sticks are notbeing used anymore.
They were in use in our country until 80s
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After introducing the Epoxy Glass Sticks,Wooden Sticks were eliminated and Epoxy GlassSticks are being used with attaching metallic
accessories.Epoxy Glass Sticks are made up of
thousands of epoxy glass resin impregnatedglass fiber laid lengthwise and wound on a
unicellular glass foam core, which is madeup of millions of unconnected cells filled withinert gas which inhabits moisture absorptionand condensation.
EPOXY GLASS STICKS
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Advantages of Epoxy Glass Sticks
Superior than wooden sticks Handling is easy because of light weight. Mechanically stronger
Higher insulation value (100 KV / foot) Moisture resistant.
Unaffected, due to sudden changes in Temp. oratmospheric conditions.
No effect due to chemically polluted atmosphere.
Maintenance is easy. Orange colour for easy identification
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Live Line Maintenance Techniques
Live Line Maintenance Techniques (LLMT) can beclassified into
1. Hot Stick Method (HSM)
2. Bare Hand Method (BHM)
3. Mixed of the above two methods
Originally LLM Techniques were developed to maintain theTransmission Lines, later-on the same techniques wereimplemented in sub-station maintenance also by followingcertain precautions like Safe Clearances, Hot-Line Tool
Maintenance, Training etc. Hotline works in a sub-station are to be carried out by the
trained persons only.
Hence the course was designed accordingly in HLTC, Bangaloreand named as Sub-Station Maintenance using Hot-LineTechniques.
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Hot Stick Method (HSM)
In this method theworking personnel will beat earth potential on the
tower / cross arm and willbe away from energizedconductor. He will attendthe work with insulatedsticks for replacement or
installation or tighteningor removal of any sort ofequipment in the line/sub-station.
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SAFE WORKING DISTANCES
(OSHA Stds.) #
Phase to phase Safe clearance
KV FEET METRE
11 20 0.6133 24 0.71
66 30 0.91
110 34 1.02
132 36 1.07
220 50 1.52
400 70 2.13
# Occupational Safety & Health Administration
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Safe working distances usually followed
in Hot-Line wings in APTRANSCO
Phase to
phase
Voltage
Clearance given in
OSHA std.
Followed in
APTRANSCO
Feet Mtrs Feet Mtrs
132 KV 36 1 50 1.5
220 KV 50 1.5 70 2
400 KV 70 2 90 2.5
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Bare Hand Method (BHM)
In this method the workingpersonnel will wear a conductivesuit (includes bonded shirt &pant, socks, gloves andconductive shoes) and away fromearth potential keeping safeclearances by way of an insulatedladder or insulated vehiclemounted boom bucket and thenhe will be charged to the livepotential.
Charged person will bondhimself to the live conductor andcarryout the work by taking allthe electrical and mechanicalsafety aspects.
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Bare Hand Dress or Hot Line Suit
Which consist of 75%nomex flame resistant fiberand 25% microscopic
stainless steel fiber.Shirt and pant have to bebonded properly.
Gloves, Socks and Shoesmust be conductive.
Once a person gets charged tothe line potential, he must bebonded to line with a bond.
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Mixed of the above two methods
Combination of
HSM and BHM
are used in all
the voltages by
observing the
field conditions
like clearances,atmosphere, line
crossings etc.
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Classification of Hot-Line
Maintenance Works
Hot-Line Maintenance ofTransmission Lines.
Hot-Line Maintenance of Sub-Stations.
Live line washing of insulators.
Emergency restoration system.Thermo-vision Scanning of Linesand Sub-Stations.
Detection of Punctured Insulator.
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Types of Hot-Line Maintenance works in
Transmission Lines & Sub-Stations
1. Replacement of Flashed over / Chipped
insulators
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2. Replacement of sub-standard insulators
(LPL make Insulators)
3. Replacement of polluted insulators
(Insulators near Chemical plants, Cement plants,Thermal plants (Nava Bharat) etc.)
4. Removing of extra insulators
In a cold line they could not able to replaceexact no. of disks because of various reasons,loading, traffic control etc.
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5. Addition / Removing of insulators (If a conductor is indamaged condition, the tension load has to be reducedtemporarily, to maintain the ground clearancetemporarily)
The above five operations can be carried insuspension, Pilot, Tension, V, and Double Stringtype.
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Suspension Operation (Video)
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VString Operation (Video)
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Tension Operation (Video)
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6. Replacement or Removing of defective fittingsand accessories like Arcing Horns, VibrationDampers, Spacer Clamps etc.
.Arcing Horn
Loosened and
fallen on conductor
and damaged the
portion of armour
by taking a spark,
further which may
lead damage of
conductor andbreakdown of the
line.Before Removing After Removing
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7. Measurement of clearances at railway
crossings, NH crossings etc.
8 P idi f Bi di i l t
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8. Providing of Binding or repair sleeves to
the un-wound portion of conductor.
9. Providing of By-Pass to the damaged
portion of conductor which gives both
Electrical and Mechanical strengths
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10. Replacement of damaged jumpers.
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11. Connecting of New jumpers of New bay
/ Feeder / PTR etc.
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Transformer upgraded from 100 MVA to 160 MVA 132
KV LV twin conductor jumper connection to Bus
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12. Tightening of Clamps to arrest the hot spots.
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13. Measurement of Jumper Lengths.
14. Providing of By-Pass to the Hot-Spotted Hard-
Ware
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15. Replacement of Isolator (Video)
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Live Line Washing.
Dust, chemicals and saline may get accumulated on
insulators due to nearness of cement factories, chemical
factories and proximity of sea. These accumulated particles
unless removed will cause the failure of insulator string.
In view of the non availability of line clear on major
feeders / sub-stations for cold line cleaning, live line
washing is employed.
Live line washing is one of the Hot line maintenance work
which is being implemented to clean the dust accumulated,
chemically contaminated and saline contaminated
insulators by the following methods.
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Dry Washing : In this method washing of insulators will be done by
using huge hot air along with corn husk or paddy husk with limestone
granules, which will be injected through nozzles on the insulators to
clean the contamination. This method is being used to clean the dust
and cement contaminated insulators. After completion of washing athin film of silicon compound may or may not be sprayed on the
insulators by hot spray. The periodicity of cleaning will be reduced by
applying silicon compound
Wet Washing : In this method washing of insulators will be done by
injecting high pressured de-mineralized water with conductivity lessthan 200 micro mhos, with the pressure of 600 PSI. This method is
being used to clean the dust, chemical and salt contamination which
are soluble in water. Mainly this method is being used in coastal areas.
Wet washing involves pumping de-mineralized water jet with the
help of equipment designed for this purpose only where precautionswill be taken for protecting human life.
Live Line Washing Methods
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Live Line Washing of Transmission and Distribution Lines(Video)
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Live Line Washing of Sub-Station Equipment(Video)
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Emergency Restoration system
Supply restoration by way of bypassing the
defective equipment temporarily.
Ex: 1. Bypassing of Defective isolator in aphase.
2. Tapping of supply from the live line.
M th d f ti i l i t
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Methods of noticing a complaint
Thermo vision camera senses temperature on the metallicobjects by its radiation. When there are loose contacts atthe joints such as T clamps, PG clamps and pad clamps
etc. The camera can detect the temperatures which are notvisible to naked eye.The camera helps in predictive maintenance i.e., it predictsthe upcoming problems so that we can plan and rectify theproblems.
The periodicity of scanning with thermo vision camera isapproximately 1 year for 132 KV SS and 6 months for 220KV SS and 3 months for 400 KV sub-stations. But basedon the field requirements, such as due to overloading ofsub-stations, the scanning may be done more frequently.
1. Hot-Spots can be identified in Lines and Sub-Stations by
using Thermo vision camera.
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Thermo vision Camera
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Hot Spots noticed by Thermo vision
Camera
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Status of defect based on the
temperatures noticed in Camera
Difference in temperature betweenmeasured and ambient
Status Designated as
10oC above ambient Normal
11 - 20oC above ambient Alert (Hot)
21 - 25oC above ambient Alarm (Very Hot)
> 26oC above ambient To be attended immediately (Critical)
Temperatures measured in Camera includes ambient
temperature.
This information is collected from the Technical Book
prepared by Central Board of Irrigation and Power
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Reasons for developing Hot-Spots
Over a period of time, resistance of conductor-joints increases mainly due to corrosion. Hot spotdevelops if the contact resistance increases more
than 80 micro-ohm. The contact resistance up to30 micro-ohm is considered safe.
Not proper fixing of nuts and bolts.
Loosening of nuts and bolts due to vibrations
Due to the Fault CurrentsPoor Quality of Hard-ware
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2. Testing of insulators using on-line insulator tester or
PUNCTURED INSULATOR DETECTOR (PID).
Introduction
The PID kit is used to detect the Punctured insulator discs in
the charged line condition. It consists of the three major parts
namely Field Probe, Sled and Telescopic Epoxy Glass Stick.Safety Precautions
Before using the PID ensure that the line is kept in Non-
auto mode at both ends.
Use the appropriate precautions i.e wearing of ConductiveShoes, Socks, Gloves, Safety Belt and Helmet while
performing the scanning.
Scanning shall be preferably done in a dry weather
condition.
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Before starting the scanning, ensure that the probe is in chargedcondition.
Mount the probe in the sled and then connect the Telescopic stick withthe sled arrangement.
Switch ON the [ON/OFF] button provided in the field probe.
Press the push button on the probe and place the PID Kit on theinsulator string and slide it to the start of the string (ground end).
Wait for at least 10 seconds until Long Beep.
Slide the kit to other end (ground end to conductor end) and a shortbeep sound will conform the scanning of each disc.
For Tension insulator forward and backward scanning is done and forSuspension insulator only forward scanning is done.After completion of the scanning, press the push button in probe tostore the scanned data.
Then wait for at least 5 seconds and then repeat the same procedure toscan another string.
Procedure for Testing of Insulator
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Down loading of DATA into a PC
Before down loading the DATA, the PID Software (Windowsbased) should be installed in the PC provided by Supplier.
Connect the charging cable to supply and join the RS 232 PIN tothe field probe and to the PC as shown in the inter connectiondiagram
Double click the PID icon in the Desktop and click the MoveData from probe to PC button.
Select the COM1 port and click the Get data from the probe andselect the folder where the data is to be saved.
Then press and hold the push button in the probe within 10
seconds till the data is down loaded in to the respective folder.
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Graph printing
Double click the PID icon in the Desktop and clickthe Graphics button.
Then open the down loaded PRN file from the
respective folder. Click the Print button to print the graph.
Scroll the mouse to view the next graph and to printit.
Repeat the above 2 steps to print all the graphs.
Sample Graph
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p p
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Tabulation of results and Analysis
The analyzing of the PID test results is done byusing MS EXCEL Software
The status of each disc is determined by the % DIPduring Forward and Reverse scan of the string
If the % DIP is more than 25 then it is inCRITICAL stage and if it is between 25 to 15then is in ALERT stage and less than 15 is in
IGNORE stage
General Specifications of POSITRON make PID probe
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p p
Sl. No. Parameters Specifications
01. Maximum insulators per string. 55 Nos.
02. Minimum insulators per sting. 04 Nos.
03. Maximum corona protection. 01 Million volts.
04. Minimum electrical field. 10 kV/meter.
05. Maximum memory capacity.300 strings or 15,000 readings (which ever
comes first).
06. Maximum scanning speed. 6 insulators per second.
07.Maximum time between uploading of
cumulated data.12 Days.
08. Maximum time between battery charges. 12 hours.
09. Minimum time of battery recharging. 10 hours.
10. Operating temperature range for the probe -30 C to 50 C
11. Dimensions 14 x 19 x 9
12. Weight 3.5 pounds
13. Calibration500 linear graphical units = 100 kV/meter
longitudinally
14. Size of insulator9 to 13
3 Physical observation of Insulators by
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3. Physical observation of Insulators byclimbing Tower while Patrolling Lines.
4. Physical observation of hard-ware andconductor while inspecting a Sub-Station.
After receiving the complaint from fieldstaff, the hot-line staff will plan andattend the complaint by using the abovesaid Hot-Line Maintenance Methods
accordingly.
C ti i t i H t Li
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Cautious points in Hot-Line
Maintenance
Hot-Line Maintenance work can be attended in the
presence of Current and Voltage provided that there
is no possibility of breakage of Current in that
particular portion during the time of maintenance.When ever there is a possibility of breakage of
Current, it has to be free from current flow by way
of tripping that particular feeder and the potential as
it is only.
The Hotline works will be carried only in dry
weather conditions.
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Hot Line ROPES
Natural fibre rope cannot be used for hotline
works because
Low dielectric strength.
Working load reduces to 50% after about six
months of continuous use.
Synthetic fibre ropes
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y p
Poly Dacron
1. White in colour2. Mechanically strong & durable3. Good for sliding hitches4. Dielectric strength is 110 KV / ft
Disadvantage: Elongates under heat,
Develops heat due to friction,
Strength gets affected.
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Poly Propylene
1. Smooth and Yellow in colour2. Very good dielectric strength (140 KV / ft.)3. Mechanically strong & durable
Disadvantage: Elongates under heat,Develops heat due to friction,Strength gets affected.
KNOTS IN HOT LINE OPERATION
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KNOTS IN HOT LINE OPERATION
Used for joining two ropes or rope to an object.
Should be easily tied and opened withoutdamaging the ropes.
Kind of knots: In hot lines, the following knots are beingused frequently.
Half Hitch Clove Hitch Square Knot Bowline Knot
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Tools normally used for hot line maintenance
Epoxy Glass Sticks1 Wire tong2.Tie stick3.Strain carrier poles.4.Ladders5.Grip All Stick6.Universal Sticks
7.Approach Stick8.Cradle Sticks9.Strain Link Sticks10.Measuring Stick etc.
M lli T l
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Metallic Tools
Most of the metallic accessories / tools are made up of heat treated
Aluminium alloy, which are light weight and more strength, some are with
Brass and some are with Steel.
Some metallic tools are attached permanently with epoxyglass sticks and some will be attached based on the work.
Different types of metallic tools used: Front and Back Yokes Tower Arm Yoke
Strain Carrier Pole Clamps Hand Line Pulleys Cradle Clamps Cum-a-along-clamp etc.
MAINTENANCE OF HOT LINE TOOLS
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MAINTENANCE OF HOT LINE TOOLS
1. Keep the Hot Line Tools on tarpaulin or on hot stick racks only.2. Clean all the tools with wipening cloth before every use.3. Clean all the Epoxysticks with moistureeater (Acetone)-MEK
(Methyl, Ethyl and Ketone).
4. Lubricate rotating parts by graphite powder. Do not use grease oroil5. If due to rain tools get wet, clean and dry thoroughly before using.6. In case it is broken it should be rejected. No repair of metal parts
is recommended7. Check the insulation strength of sticks with Hot Stick Tester.8. If there are any voids on the stick, fill it with epoxy glass bond and
on becoming it stiff, apply a layer of epoxy glass restorer forshining.
9. If the shining has gone, rub the stick with emery paper, clean withmoisture eater, apply a layer of epoxy glass restorer for shining.
Ladder Monitor Kit
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Ladder Monitor Kit
For EHV Micro-amp Measurement onBare-hand Equipment
The Ladder Monitor Kit is used inconnection with EHV Bare-handmaintenance procedure to detect micro-ampleakage on the ladder before it is placed intouse. This is accomplished by connecting themeter to the ladder, and taking readings as
the ladder is placed in contact with theconductor. It is recommended that readingsbe taken periodically during work progressto assure proper or optimum workingconditions which could be altered by achange in the atmosphere. The kit consists ofa 200 micro-amp scale micro-ammeter, threeclamps to effect use on a three-rail ladder, acable with clips and adapter to establishcontact, a bracket to ground and hold themeter on the structure and two dry cellbatteries. Instruction drawings for fieldassembly are also included in the kit.
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Limitations of Leakage Current
Thumb rule for calculating leakage current in
micro-amps ~ Line Voltage / 3
S.No.Line Voltage in
KV
Leakage Current in
micro-amps
Approximate value of Leakage
Current in micro-amps
1 132 44.00 45
2 220 73.33 75
3 400 133.33 135
If the value in monitor kit below the above values thenonly the person is allowed to climb, if not ladder must be
brought down and cleaned once again. Even-though no
improvement is found, it has to be kept away and sent
for lab testing.
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0 - 1 mA Cannot feel anything
1 - 8 mA Can feel but no pain
8 - 12 mA Painful but can let it go
12 - 20 mA Freeze, cannot let go
20 - 50 mA Breathing stops
50 - 200 mA Heart stops
200 and above Sever Burns
Effect of Current flow in body
S f th H t Li T l U d
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Some of the Hot Line Tools Used
Universal Tool Kit : Universal Tools are required to handle cotter keys,
Bolts and nuts, ball and socket etc.
HAND LINE HOOK : Usually it is fixed to the hand line to lock the tools and
materials, so that the tools will not fall while lifting and downing.
Shepherd Hook: Shepherd Hook is used for pulling and lifting insulator
strings. Swivel action permits it to rotate and maintain its alignment with
the insulator at all times
ADJUSTABLE INSULATOR FORKS : Used for holding and guiding the
insulator while engaging to line hard-ware.
Pin Holder : Manipulation with pins and bolts. Bolt head fits into a slot and is held tight by
spring action.
UNIVERSAL ADAPTER : It is Used for connecting universal tools at different angles. Means
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UNIVERSAL ADAPTER : It is Used for connecting universal tools at different angles. Meansthat when this adapter is mounted on a universal stick any universal tool can be set at almost any
angle to the stick.
Locating Pin : Used as a drift pin in aligning bolt holes as an aid in bolt and
pin.
Conductor Cleaning Brush : Used to clean the conductor in polluted areas
HAMMER : Used to break the insulators and wherever the impact load isrequired
CLEAR VISION MIRROR : To view the non visible objects
Ratchet Wrench : It is used for tightening of bolts.
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FOLDING Scale : Used for measurement on live line
SKINNING KNIFE : To remove the unwanted particles from live portion likerust, scales, etc.
Cotter Key Puller : used to partially withdraw a ball-socket cotter key so
that the insulator can be removed
M - Pin Pusher : Used for ball and socket insulator coupling. Straightend of the Curved end forces cotter key back into position.
COTTER KEY REMOVER : Used to remove the cotter keys
FLEXIBLE WRENCH HEAD : Used for tightening nut and bolts in anyangle
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HACK SAW : Used to cut the un-wanted things
Set off Rope Blocks : Used to take load easily
Suspension link Stick : Used to hold the conductor in the operation of
suspension string replacement
CHAIN RATCHET HOISTS : Used for loading in 400 KV operations.Normally One-Ton, Two-Ton and Three Ton Hoists are being used in Hot-
Lines
Cotter Key Installing Tool : Used for replacing cotter keys
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Universal BRUSH
To paint the live parts
To lubricate the live parts
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Cement
accumulation on
the conductor.
132 KV SS, Wadapally in Nalgonda District
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BALL SOCKET ADJUSTER
Used for adjusting Ball and Socket of Insulators
V - Type C - Type
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Designed to grasp from anyangle, and tighten byclockwise rotation of theUniversal Tool handle.
Used as a holding device forretaining bolt heads andloose hardware, adjustingarcing horns, replacingcotter keys, etc.
All Angle Pliers
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Used for engaging hot-line tools like Cum-a-along clamp, poles etc..
Grip-All Clamp stick
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Normally used for holding liveconductors
To maintain the clearances fromworking area
To transfer the conductors toknee positions.
Wire Tong
Sli d Adj t bl St i C i P l
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Sliced Adjustable Strain Carrier Pole
In this case Strain Carrier Clamps will not be used, these
poles are used mainly in 400 KV operations.
Types of Cradles
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Assembly of Tension String Operation
A bl f D bl S i O i
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Strain carrierPoles in doublestring operation
Used for relieving thestrain on Insulator
String while changinginsulators on DoubleString TensionOperation.
Assembly of Double String Operation
Suspension operation
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Strain link
sticks
Used for supportingconductor loads when
changing insulators onSuspension Strings.
Strain Carrier Pole Accessories
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Take-up Trunnions
Strain Jacks
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Capstan Hoist
Capstan Hoist isused to lift up thetools and materialsrequired for the
maintenance work.
A h S i k
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Approach Stick
This stick is used to approach
the lengthy jumpers because
when the length of the jumper
increases the discharge currentis more and it is difficult to
touch directly. Hence lengthy
jumpers will be approached
with this approach stick and
then the jumper will behandled further.
Some of the defects Experienced
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Scaffolding Operation
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g p
Private Work Carried at Spectrum
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Hot Line Tools will be carried in a
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specially designed vehicle
Energy Saving
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gy g
By carrying out such works Hotline crew are saving lot ofrevenue to the department. Energy saving is calculated as follows.
Cost of 1 unit is considered as Rs. 2.27 /-
Cost of 1 unit in Lacks = Rs. 2.27 / 105
Cost of 1 MU (106 Units )in Lacks = Rs. (2.27 / 105) X 106
Cost of 1 M unit = Rs. 22.7 Lacks
Saving in Rs in Lacks = No. of M units X 22.7Saving in Rs in Lacks = Load in MW X Time of operation X 22.7
In addition to the departmental works, APTRANSCO has alsorendered their services to the external agencies like NTPCRamagundam, Visakhapatnam Steel project, Spectrum and MidhaniHyderabad.
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Sample Saving
SAMPLE PICKED UP FROM HOT-LINES PROGRESS REPORT of HLSD, MC, HYD. from the month of April - 2009
Name of the Hot-Lines Sub-Division: Metro Circle, Hyderabad
S.No Date Name of the SS / LineType of
WorkLocation Details of Works
Load
in
MW
No.
Of
hour
s
M.U.
Saved
Revenue
Saved
in Lakhs
of Rs.
1 2/4/09220 KV Ghapapur to
Malkaram Feeder-I
BHM &
HSMLine
LOC No. 15 near Ghanapur
Railway Crossing double string
cut point Top phase LPL disc
Insulator strings replaced.
180 5 0.90 20.43
2 14/4/09220 KV SS Chandrayana
Gutta
Scanning SS
Thermovision Scanning of
220 KV SS Chandrayana Gutta
carried out.
_ _ _ _
Total M.U and Revenue in Lacks of Rs. saved 0.90 20.43
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Saving in one year (200809)
Performance Report of Hot Line Sub-division Metro Circle, Hyderabad for the financial year 2008 - 09
SI.No. Month HSM BHT Scanning OTHTotal
Operations
EnergySavedin MU
Revenue Saved in
Lakhs of Rs.
1 Apr, 2008 4 11 2 3 20 7.08 160.72
2 May, 2008 18 15 1 - 34 6.99 158.67
3 Jun, 2008 10 28 4 - 42 9.45 214.52
4 Jul, 2008 5 29 4 - 38 8.77 199.12
5 Aug, 2008 5 9 7 1 22 1.58 35.84
6 Sep, 2008 8 14 1 - 23 5.22 118.52
7 Oct, 2008 8 11 3 1 23 4.43 100.45
8 Nov, 2008 7 9 9 - 25 3.79 86.06
9 Dec, 2008 17 5 8 1 31 8.22186.48
10 Jan, 2009 13 30 4 - 47 15.31 347.51
11 Feb, 2009 5 14 5 - 24 5.43 123.31
12 Mar, 2009 13 14 11 - 38 7.71 174.97
Total 113 189 59 6 367 83.97 1906.16
Graphical Representation of Progress
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p p g
0
5
10
15
20
25
30
35
40
45
50
Apr,
2008
May,
2008
Jun,
2008
Jul,
2008
Aug,
2008
Sep,
2008
Oct,
2008
Nov,
2008
Dec,
2008
Jan,
2009
Feb,
2009
Mar,
2009
HSM
BHT
Scanning
OTH
Total Operations
Energy Saved in MU
Courses offered in Hot-Lines
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Training Centre
Hotline works are to be carried out by the trainedpersons only.
There are basically four types of training.1. Hot stick method (3 Months).
2. Bare-hand method (1 Month).3. Live line washing (1 Month).
4. Sub-Station Maintenance (1 Month).
There is only one training institute, HotlineTraining Centre (HLTC) in south Asia which islocated at Bangalore.
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