HANDBOOK ON TESTING INSTRUMENTS REQUIRED...2.2 winding resistance measurement 04 2.3 winding insulation resistance measurement 05 2.4 capacitance & tan delta measurement 06 2.5 transformer

CAMTECH\E\2007\SVCB\1.0

Maintenance Handbook on Single Interrupter Vacuum Circuit Breaker (Type 22CB) February, 2007

1

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HANDBOOK ON

TESTING INSTRUMENTS REQUIRED

FOR

CONDITION BASED MAINTENANCE OF

TRD ASSETS

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CAMTECH/E/2009/TI-TRD/1.0

August 2009

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2

QUALITY POLICY

“To develop safe, modern and cost

effective Railway Technology

complying with Statutory and

Regulatory requirements, through

excellence in Research, Designs and

Standards and Continual

improvements in Quality

Management System to cater to

growing demand of passenger and

freight traffic on the railways”.

TESTING INSTRUMENTS REQUIRED

FOR

CONDITION BASED MAINTENANCE

OF

TRD ASSETS



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FOREWORD

The present trend world over is to minimize maintenance on the equipment as

disadvantages of over maintenance are well known and understood. This can be

achieved by the concept of condition based maintenance wherein the condition of the

equipment is judged based upon the “trend of values of certain parameters over a

period of time and not upon their absolute values”.

This handbook covers details of such instruments which are useful in condition

based monitoring of TRD assets. Necessary information such as make, model, technical

specifications and sources of supply have been included for reference.

CAMTECH, GWALIOR S. C. SINGHAL Date:29.09.2009 EXECUTIVE DIRECTOR



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PREFACE

With the increase in traffic, getting a block to maintain the different Railway assets is increasingly becoming more and more difficult. To carry out the optimum maintenance (in right quantity and at the right moment) condition monitoring techniques are of great help.

By employing condition based maintenance techniques the disadvantages of

‘breakdown maintenance’ & ‘scheduled maintenance’ can be avoided. The maintenance can be planned just at the time it is really required, thus avoiding failures and also saving the precious block time.

This document has been compiled by CAMTECH and gives a ready reference of

all the condition based maintenance equipments available which can be used for the above purpose.

It is clarified that this handbook does not supersede any existing provisions laid down by RDSO or Railway Board. This handbook is for guidance only and it is not a statutory document.

Technological upgradation & learning is a continuous process. Please feel free to write to us for any addition/ modification in this handbook. We shall highly appreciate your contribution in this direction.

CAMTECH, Gwalior JAIDEEP Date: 25.09.2009 Director Electrical



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CONTENTS

Serial No. Description Page No.

Foreword iii Preface iv Contents v

Correction Slip vii

1.0 OBJECT 01

1.1 BENEFITS OF CONDITION MONITORING 01

1.2 VARIOUS EQUIPMENTS TO BE MONITORED 01

2.0 TESTING INSTRUMENTS FOR TRANSFORMERS 02

2.1 PARAMETER TO BE MONITORED AND WHY 02

2.2 WINDING RESISTANCE MEASUREMENT 04

2.3 WINDING INSULATION RESISTANCE MEASUREMENT 05

2.4 CAPACITANCE & TAN DELTA MEASUREMENT 06

2.5 TRANSFORMER TURN RATIO MEASUREMENT 08

2.6 DISSOLVED GAS ANALYSIS 10

2.7 FAULT GAS AND MOISTURE MONITORING 12

2.8 OIL TAN DELTA MEASUREMENT 14

2.9 OIL BREAK DOWN VOLTAGE MEASUREMENT 16

2.10 SWEEP FREQUENCY RESPONSE ANALYSIS 18

3.0 TESTING INSTRUMENT FOR CIRCUIT BREAKERS/ INTERR UPTERS 20

3.1 PARAMETERS TO BE MONITORED AND WHY 20

3.2 DYNAMIC CONTACT RESISTANCE MEASUREMENT 21

3.3 CONTACT RESISTANCE MEASUREMENT 23

3.4 TIME INTERVAL MEASUREMENT 24

4.0 TESTING INSTRUMENTS FOR CURRENT TRANSFORMER 25


4.2 CURRENT TRANSFORMER EXCITATION, RATIO AND POLARITY

MEASUREMENT 26

4.3 CURRENT TRANSFORMER BURDEN MEASUREMENT 27

5.0 TESTING INSTRUMENT FOR SURGE ARRESTER 28


5.2 LEASKAGE CURRENT MEASUREMENT 29

6.0 TESTING INSTRUMENT FOR RELAYS 31

6.1 PERFORMANCE TESTS TO BE DONE ON RELAYS AND WHY 31

6.2 PRIMARY CURRENT INJECTION TEST 32

6.3 SECONDARY CURRENT INJECTION TEST 34



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7.0 CHECKING OF ELECTICAL CONNECTIONS 35

7.1 LOOSE CONNECTIONS AND HIDDEN FAULTS CHECKING 35

7.2 INFRARED THERMAL IMAGING CAMERA 35

8.0 TESTING INSTRUMENT FOR MEASURING EARTH RESISTAN CE 37

8.1 EARTH RESISTANCE 37

8.2 EARTH RESISTANCE AND RESISTIVITY MEASUREMENT 38

9.0 TESTING INSTRUMENTS FOR BATTERIES 39

9.1 PARAMETERS TO BE CHECKED AND WHY 39

9.2 BATTERY ANALYSIS 40

10.0 TESTING INSTRUMENTS FOR WIRES/ CABLES 42

10.1 WIRE TRACER/ CABLE LOCATOR 42

10.2 CABLE ROUTE TRACER 43

11.0 TESTING INSTRUMENTS FOR OVER HEAD EQUIPMENT 45

11.1 CONTACT WIRE SPARK CHECKING 45

11.2 CONTACT WIRE HEIGHT & STAGGER MEASUREMENT 47

11.3 LIVE LINE CONTACT WIRE WEAR MONITORING 48

11.4 LIVE LINE INSULATOR CLEANING 49

ANNEXURE – I Sources of Supply 50



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ISSUE OF CORRECTION SLIP

The correction slips to be issued in future for this handbook will be numbered as follows: CAMTECH/E/2009/TI-TRD/1.0/ C.S. # XX date--- Where “XX” is the serial number of the concerned correction slip (starting from 01 onwards).

CORRECTION SLIPS ISSUED

Sr. No. Date of issue Page no. and Item no. modified Remarks


Testing Instruments Required for Condition Based Maintenance of TRD Assets August, 2009

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1.0 OBJECT

Indian Railway is one of the largest railway system in the world using 25 kV AC single phase, 50Hz traction supply system. It employs various equipments and infrastructure in PSI & OHE to keep the system working efficiently. It has been experienced that significant numbers of failures of PSI & OHE are because of components failure and lack of maintenance due to non availability of power block.

Keeping the increasing trend of traffic in mind it is desired to reduce maintenance

time by employing modern instruments in the field of maintenance.

It is felt that condition based maintenance instruments should be available with the TRD maintenance staff. These instruments may play key role to improve quality of work, with least block time which will improve system reliability and availability.

In order to minimize outages due to equipment failures, modern condition based

maintenance techniques needs to be implemented in maintenance of TRD assets to predict deterioration of various components.

1.1 BENEFITS OF CONDITION MONITORING

• Reduction of un-planned outage. • Predictable maintenance schedule. • Prevention of costly failure. • Minimize the severity of damages. • Increase the system stability. • Helps to plan future renovation.

• Use of equipment for maximum economical efficiency. 1.2 VARIOUS EQUIPMENTS TO BE MONITORED

• Transformers

• Circuit Breakers/ Interrupters

• Current Transformers

• Surge Arrestors

• Relays

• Electrical connections

• Earth pits

• Batteries

• Cables

• Machines

• Contact wire

• Insulators



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2.0 TESTING INSTRUMENTS FOR TRANSFORMERS 2.1 PARAMETERS TO BE MONITORED AND WHY 2.1.1 Winding Resistance

The measurement of DC resistance of winding of transformers, motors etc. are

required.

to verify manufacturer test readings.

to check winding health during regular maintenance.

to locate the presence of defects such as loose connections, open circuit etc.

2.1.2 Winding Insulation Resistance

The monitoring of winding insulation resistance is very essential to predict the following defects.

Insulation failure between winding and core (earth).

Insulation failure between winding to winding.

Insulation failure of bushings, internal connections etc.

2.1.3 Capacitance and Tan Delta Capacitance and Tan Delta are most important parameters of insulating materials. In particulars tan delta gives the true picture of health of insulation. The above results can be interpreted to reveal the quality of insulating system and manufacturing process defects like contamination, fracture or puncture. It can also be used to find out defects which develop in field due to ageing and other factors.

2.1.4 Transformer Turn Ratio & Phase Angle Deviatio n

Transformer turn ratio is the ratio of the number of turns in the high voltage winding to that in the low voltage winding. The phase angle deviation, displayed in either degree (minutes) or radians, is the phase relationship between the voltage signal applied to the high voltage winding and the voltage signal extracted from the low voltage winding. This phase deviation, together with ratio error can be used as a low cost method of verifying accurately class of all types of PTs, CTs at zero burdens.

2.1.5 DGA of Transformer Oil

The thermal & electrical stresses caused during short circuits, overloads and over voltages and deterioration of dielectric properties of insulating oil produces appreciable amount of gases in the system. These gases are soluble and are absorbed in oil.

Dissolved Gas Analysis (DGA) provides an important means in the art of condition monitoring of power transformer and other oil filled equipments. This is well suited for detection of growing faults which are not always revealed by established routine tests.



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2.1.6 Oil Break Down Voltage

Break down voltage test of insulating oil is carried out to test its dielectric strength to reveal the extend of physical pollution by water and other suspended matters. By this test need of carryout drying out, filtration treatment of the oil can be predicted.



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2.2 WINDING RESISTANCE MEASUREMENT

2.2.1 Winding Resistance Meter

Name of Instrument : Transformer winding resistance meter

Application : Transformer winding resistance meter measures the winding resistance of transformers, inductors, generators, motors, tap changers etc.

TRM – 104 (M/s.ScopeT&M Pvt Ltd Mumbai) 830280 – 47 (Megger Ltd.) WR50-12 (Raytech GmbH, Switzerland) WINDAX (Pax Diagnostics)

Models (make) :

TWRM-10A (SIVANANDA Electronics, Devlali) Technical Specifications :

Power supply 220 – 240 V AC, 50 Hz Single φ Test Current Ranges 10A, 5A, 1A and 0.1 Amp DC

Resistance Range 1 milli ohm to 199.99 ohms Resolution 0.1 micro ohm on 2 mili ohm Indication 4½ digital panel meter LCD dual channel Accuracy 1 microΩ to 1999 microΩ ± 0.5% ± 1 digit 20 mΩ to 999 mΩ ± 1.0% ± 1 digit 1Ω to 200Ω ± 1.5% ± 1 digit DC Power Supply 50 Volt/ 10A Test current range 10 Amp. (auto range selection) Data Acquisition software

Window based

Memory record 45 Records Controls Power on switch Current range selection switch Operating temp - 10°C to 50°C Storage temp - 10 °C to 70° C

Open circuit voltage 30 V DC

Advantages:

i. This instrument can measure the DC resistance of all types of winding safely and accurately.

ii. It is safe for user as it’s built in discharge circuit safely discharges the specimen when test is completed, if lead accidentally disconnected or if power is lost.



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2.3 WINDING INSULATION RESISTANCE MEASUREMENT 2.3.1 Winding Insulation Resistance Meter

Name of equipment : Winding insulation resistance meter

Application : To measure Insulation Resistance of all the high voltage components like transformer winding, CTs, PTs, bushings, cables and motor windings etc.

Models (make) : 3541 (HIOKI E.E Corporation) MI – 5000 (Sonel S.A, Poland) 5K4 (M/s. Sivananda Electronics, Devlali)

Technical Specifications :

Test voltage 500 V to 5000 V DC

IR Range 0 – 5 TΩ

Accuracy As per IS 2992

Display Analogue, Digital

Short circuit current < 2mA

Temperature range

i. Storage – (-40°C to +65°C)

ii. Operating – (-15°C to+ 55°C)

iii. Humidity range – 90% RH at 40°C

Advantages:

i. Healthiness of winding insulation can be checked.

ii. Testing of under grounded as well as grounded objects can be carried out.

iii. The equipment has a LED based provision for visual indication for discharge condition. This LED shall glow after the HT is switch OFF, till the voltage on test object/ HV terminal is below 50 V approximate.

iv. Equipment have HV, LV & Guard and Internal discharge of object after test, memory for measurement results, ability to transfer the data to a PC, polarization index and dielectric absorption ratio.



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2.4 CAPACITANCE AND TAN DELTA MEASUREMENT

2.4.1 Capacitance and Tan Delta Test Kit

Name of Instrument Capacitance & Tan Delta test kit

Application Capacitance & Tan Delta tests the health of insulation.

It can be used for testing of transformers, bushings, cables, insulators, switchgear, rotating machine, capacitors and lightning arresters.

Models (make) : MLS – 11DA/ HLS – 12A ( M/s Sivananda Electronics, Devlali)

TD – 30 (M/s HV Diagnostics S.a.r.l Switzerland)

DELTA 3000 ( Megger Ltd.)

Technical Specification

S.N. Parameter Range Resolution Accuracy

1. Capacitance 1PF – 1.1 microF (with range extension CT upto 2.6 microF)

4 digits ± 0.2% of the reading ± 1 PF (UST) ± 1 PF (GST)

2. Tan Delta 0% - 100% (infinity) 0.00001 ± 1% of the reading ± 0.05%

3. Voltage measurement

0 – 12 kV 1.0V ± 1%, ± 1 digit

4. Current measurement

0 – 2000 mA 1mA ± 1%, ± 1 digit

5. Power factor 0.01% - 100% 0 – 00001 ± 1.0% of the reading ± 0.05%



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S.N. Parameter Range Resolution Accuracy

6. Power 0 – 2 kW 0.1 mW ± 1% of reading

7. Interference current 0 – 100 mA 1 mA ± 1% of reading

8. Analysis software Windows based analysis software for Tan delta Vs time, Tan delta Vs voltage

9. Temperature range - 10°C to 50°C

10. Humidity range Ambient to 95%

Advantages:

i. These results can be interpreted to reveal the quality of insulating system and manufacturing process defects like contamination, fracture or puncture.

ii. It can also be used to find out the defects which develop in field due to ageing and other factor.

iii. This instrument can measure the capacitance & Tan delta automatically by auto balancing.

iv. This instrument is suitable for extraneous conditions in 400 kV switch yard under heavy induction.

v. This instrument indicates leakage current, magnetizing current & leakage reactance.

vi. The instrument can take measurement at line frequency as well as fixed generated frequency so that the out put frequency is independent of change in input frequency.

vii. Data logging with graph of voltage Vs Tan Delta to know the Tan Delta gradient & data analysis for comparison with old results, printout can be taken at site.



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2.5 TRANFORMER TURN RATIO MEASUREMENT 2.5.1 Transformer Turn Ratio Meter

Name of instrument Transformer turn ratio meter

Application Microprocessor based Turn ratio meter is used for automatic measurement of voltage/ turn ratio, current and phase displacement of power transformers, CTs and PTs.

Model ( make) TR mark – II ( Raytech GmbH, Switzerland)

TTR 300 (Megger Ltd.)

ATRM-RM-1uP (M/s Sivananda Electronics, Devlali)


Power supply 240 V AC, 50Hz single phase

Test voltage 110V AC 60 Hz on request

4.8 V, 48 V ac

Auto ranging Ranges

Indication 4½ digit LED display of ratio LCD display

Accuracy ± 0.2 % for ratio reading 5 to 1000 ± 1.5% for range beyond 1000.

Test plan storage 120 test plans

Weight app. 8 kg to 17 kg. Auto ranging Ranges

S.No. Ratio Range Display Resolution Accuracy 1. 10 1 – 9.999 0.001 2. 100 10 – 99.99 0.01 3. 1000 100 – 999.9 0.1 4. 10000 1000 – 10000 1 5. 14000 10 000 - 14000 1

± 0.2% for ratio 5 to 1000 ± 1.5% for ratio beyond 1000



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Advantages: i. It is a remote controllable and can works in the presence of high interference/ high

voltage. ii. It measures phase deviation of the transformer primary vs. secondary, quickly

indicates problems in the transformer such as partial shorted turns and core faults. iii. It is also useful in verifying phase error in PTs, CTs at zero burdens. iv. This instrument have auto operation, no balancing is required, LCD display, fully

protected against any wrong connections.



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2.6 DISSOLVED GAS ANALYSIS 2.6.1 Transformer Oil Multiple Gas Extraction Syste m

Name of instrument Transformer oil multiple Gas Extraction System

Application Dissolved Gas Analysis is carried out to detect the dissolved gases in transformer oil. It deals with the methods of sampling, extraction and analysis of incipient fault gases in part per million (PPM) levels from a small quantity of transformer oil sample.

Model (make) D Tomget-1207, (M/s Dakshin Lab Agencies,Banglore) ASTM 3612 and IEC 567 (Energy Support, Germany)


Vacuum pump Direct drive rotary vacuum pump (air cooled) with single phase motor of displacement capacity 250 ltr./ min. particle discharge pressure with gas ballast closed 5 x 10-

4m bar.

Vacuum guage Digital Pirani gauge with pressure range 0.999 to 0.001 m bar. Display – 3 digit LED numeric with under range and over range indicators.

Gas extractor (Patented)

Designed for exposing same sample oil to multiple extractions. To hold vacuum of 0.1 m bar with minimum efficiency of 97% gas extraction,

Stand Vibration free heavy duty stands with suitable clamp to hold gas extractor.

Mercury 10 kgs

Magnetic stirrer

Power distribution board with pirani gauge fixed on it.

Accessories Hand pump, vacuum tubes, keck clips, vacuum grease, and spares like septum, magnetic bar and screw cap.



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Advantages:

i. Dissolved Gas Analysis (DGA) provides an important means in the art of condition

monitoring of power transformer and other oil filled equipments. ii. This is well suited for detection of growing faults which are not always revealed by

established routine tests. iii. This equipment is designed and developed with an improved method for extraction of

dissolved gases, considering the fact that even small traces of certain dissolved gases in transformer oil are to be detected, to identify a fault in transformer.

iv. Efficiency is more than 98%.



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2.7 FAULT GAS AND MOISTURE MONITORING 2.7.1 M2 Fault Gas & Moisture Monitor

Name of instrument M2 fault gas & moisture monitor

Application This instrument is applicable in oil filled equipments to regularly monitor the fault gases and moisture as an early warning device that will alert personnel about developing fault conditions that could lead to equipment failure and unscheduled outages.

This instrument combines two products in one. First is fault monitor that reads a composite value of gases in ppm, generated by faults and provides output capability for communication.

Second is moisture level sensor for the evaluation of dangerous condition such as bubbling, temperature and asset management information such as rate of ageing of the insulation.

Model (make) HYDRAN – M2 (M/s PCI. Pvt. Ltd. New Delhi)


Components Combined dual function sensor and electronic enclosure.

Response Relative humidity in oil (%), hydrogen (H2), carbon monoxide (Co), acetylene (C2H2), ethylene (C2H4)

Medium Mineral, insulating oil for transformer

Measurement range

Moisture 0 – 100% RH

Gas 0 – 2000 ppm

Accuracy Moisture - ± 2% RH

Gas - ± 10% reading ± 25 ppm

Response time Moisture – 5 minute, sensor, response (90% of step change)

Gas – 10 minutes, sensor, response (90% of step change)

Hardware Microprocessor, watch dog, clock

Software Real- time operating system, menu-driven interface

Display Backlit liquid crystal display (LCD)

Power supply Universal 80 – 200V AC 50 Hz 350 VA

Weight 6.0 kg



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Advantages:

i. This instrument alerts personnel about developing fault conditions at an early stage.

ii. It requires single valve for both fault gas and moisture monitoring.

iii. The use of optional analog input allows basic transformer monitoring.

iv. This can be installed with no additional oil lines and uses no pumps or other moving parts for maximum long term reliability.

v. It can test continuous field measurement.

vi. It reduces unplanned outages and it is useful for predictable maintenance schedule.



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2.8 OIL TAN DELTA MEASUREMENT

2.8.1 Oil Tan Delta Test Kit

Name of instrument Oil tan delta test kit

Application Oil tan delta tests the dielectric dissipation factor & resistivity measurement of oil.

Model (make) Nil (M/s Sivananda Electcronics Devlali.)


Test voltage Capacitance tan delta dielectric constant

Adjustable from 0 to 3000 V AC in steps with an accuracy of ± 1.0%

Test frequency 50 Hz

Dielectric constant range 1.0 to 13.0 accuracy ± 0.2% ± 0.001

best resolution – 0.001

Dielectric tan delta range 10-5 to 10 accuracy ± 1% ± 0.3% full scale, best resolution 0.00001

Resistance & resistivity

Test voltage DC : 500 V DC in step with an accuracy of ± 1.0%

Resistance range 106 – 1012 Ω resolution: 3 digit

Resistance accuracy ± 3% of reading up to 1 GΩ & ± 10% at high end

Resistivity range 109 – 1015 Ω-cm best resolution : 0.01

Resistivity accuracy ± 3% of reading ± 0.2% full scale

Oil test cell

Construction 3 terminal configuration

Cell capacitance 55PF ± 1 PF

Material Stainless steel with Teflon spacers

Electrode spacing 2mm



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Volume 45 ml

Oil test cell heater

Power supply 230 V AC ± 10% 50Hz

Test temperature Adjustable from 200C (room temp) to 1500C with an accuracy ± 0.5%, accuracy of temp. control ± 20C

Display printer & data storage

Display Alphanumeric LCD display

Printer Inbuilt dot matrix printer

PC compatibility RS 232 port

Data storage upto 250 test results

Power supply 230V AC ± 10%

Operating temp (-10 to 50°C)

Humidity ambient to 90% RH

Advantages:

i. Fully automatic dielectric constant, dielectric dissipation factor and resistivity

measurement.

ii. Easy storage of the data.

iii. It has PC compatibility and inbuilt printer facility for test report printing.



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2.9 OIL BREAK DOWN VOLTAGE MEASUREMENT

2.9.1 Automatic Oil Break Down Voltage Tester

Name of Instrument Automatic oil BDV tester

Application Automatic oil BDV tester is used for determining the dielectric strength of liquid insulation such as the insulating oils used in transformers, switch gears and other electrical apparatus.

Model (make) OTSPR – 100 (C.G), (M/s Sivananda Electronics Devlali) OTS AF/2 (Megger Ltd.,)


Power supply 230V AC ± 10%, 50Hz ± 3%

Voltage range 0 to 100 kV AC

Trip current 10 mA

Indication 3½ digit panel meter

Resolution 0.1kV

Accuracy ± 2% of normal value

Variac Motorized

Shut down sensitivity

5 mA

Shut down < 20 milli second

Oil test cell Transparent acrylic material, 36 mm removable mushroom head electrodes

Gap gauge 2.5 mm

Controls mains ON/OFF, HT ON/OFF, hold, stirrer ON/OFF, timer ON/OFF, auto/ manual mode reset switch.

Features Microprocessor – control with following feature fully automatic option to set (a) stand time (b) stir time, (c) Rate of rise of voltage 0.005 kV to 5.0kV adjustable, (d) No. of test carried out as per selected standard.



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Printer Built in alphanumeric printer. Time dated result with standard deviation printed.

Software Windows based data acquisition software

Keypad Quick test selection through 12 keys soft touch key pad.

Display Large backlite LCD display to display test menu set up screens.

Storage memory 100 test results

Safety feature Interlock on high voltage test chamber, zero start protection, double ground protection. All safety interlocks to avoid shocks with indications. Protected against overloads & short circuits.

Temperature range

Operating 0 – 50°C

Humidity range 80 % RH at 40°C

Storage 5 to 70°C. Advantages:

i. Oil BDV test set is a fully automatic microprocessor controlled testing equipment.

ii. It is an operator friendly test kit.

iii. The test carried out automatically.

iv. It is a portable and laboratory unit.

v. It has pass/ fail limit and custom test facility.



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2.10 SWEEP FREQUENCY RESPONSE ANALYSIS 2.10.1 Sweep Frequency Response Analyser

Name of instrument Sweep frequency response analyzer for power transformer

Application This instrument detects internal mechanical displacements without extended downtime. This instrument detects problems such as

(i) Winding deformations and displacements

(ii) Shorted turn and open winding

(iii) Loosened clamping structure

(iv) Broken clamping structure

(v) Core connection problems

(vi) Partial winding collapse

(viii) Faulty cone ground

(viii) Core movements

(ix) Hoop buckling

Model (make) FRAX – 101( Pax Diagnostics) FRAX – 101(Megger Ltd.)


FRA method Sweep frequency

Frequency range 0.1 Hz – 25 MHz, user selectable

Number of points Default 1046, User selectable up to 32,000

Measurement time Default 64s, fast setting, 37s, ( 20 Hz- 2 MHz)

Accuracy ± 0.3 dB down to -105 dB( 10Hz- 10MHz)

Software FRAX for windows 2000/XP/ vista

PC communication Blue tooth and USB

Channels One

Compliance Voltage 0.2 – 20V peak-to- peak

Measurement Voltage at 50w

0.1-10V peak-to- peak



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Voltage output 10V peak to peak in 50 ohms.

Output impedance 50 W

Protection Short circuit protection

Instrument weight 1.4 kg

Input Voltage 11-16V dc or 90-135V ac and 170-264V ac, 47- 63 Hz

Operating ambient temp. -20°C to 50°C

Operating Relative Humidity

< 90% non- condensing

Storage ambient temp. -20°C to 70°C

Storage Relative Humidity < 90% non- condensing

Advantages:

i. Sweep frequency response analyzer detects potential mechanical and electrical

problems.

ii. The measurement is easy to perform and will capture a unique “Fingerprint” of the transformer and compared to a reference “Fingerprint” and gives direct answer if the mechanical parts of the transformer are unchanged or not.

iii. Deviations indicate geometrical and electrical changes within the transformer.



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3.0 TESTING INSTRUMENT FOR CIRCUIT BREAKERS/ INTERR UPTERS 3.1 PARAMETERS TO BE MONITORED AND WHY

3.1.1 Dynamic Contact Resistance Measurement (DCRM)

Failure of circuit breakers is because of component failure in the interrupter assembly. Mechanical breakage/damage, misalignment of contacts/ operating links, erosion of arcing contacts have been the causes of failures causing severe damage to CB poles and also to the neighboring equipments.

Dynamic contact resistance measurement (DCRM) is a very effective tool to assess the condition of main & arching contacts, erosion/ length of arcing contact, main & arching contacts insertion, misalignment of contacts/ operating links, without opening the interrupter.

The DCRM measurement can detect above faults in incipient stage and accordingly the corrective measures can be taken at right time to avoid subsequent break downs.

3.1.2 Contact Resistance

Contact resistance meter measures the resistance of circuit breaker/ interrupter when it is in close condition i.e. both main & arching contacts are in close condition and the system current flows through the main contacts due to its low resistance. If resistance value is found lesser than specified value than it shows healthiness of main contacts.

3.1.3 Time Interval

Time interval measurement is carried out to measure the timings of the closing & opening operations of the circuit breaker/ interrupter during close, trip, close-open, open-close & open-close-open operations with a provision of user defined time delay between two operations. If these timings are found within the specified limits than it shows healthiness of operating mechanism as well as gap between the fixed & movable contacts.



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3.2 DYNAMIC CONTACT RESISTANCE MESUREMENT (DCRM)

3.2.1 Dynamic Contact Resistance Measurement Meter

Name of instrument Dynamic contact resistance measurement meter

Application The dynamic contact resistance measurement meter is a very effective tool to assess the condition of main & arching contacts, erosion/ length of arching contact, main & arcing contact insertion, misalignment of contacts/ operating links, without opening the CB or interrupter.

The DCRM measurement can detect above fault in incipient stage and accordingly the corrective measures can be taken at right time to avoid subsequent break downs.

Model (make) Hisac ultima with DCRM 100 B(M/s Scope T&M Pvt. Ltd.,)

Technical Specifications

Channels Configuration Range Resolution Accuracy

Contact status 24:4 main + 4 PIR per pole, on 3 poles simultaneously

Measurement duration 1 mS to 40 Sec at 1 kC, 0.05 mS to 2 Sec at 20 kC

1 mS at 1 kC 0.05 mS at 20 kC

Value ± 0.05%

± 1 digit

Auxiliary contacts 4: 2 dry, 2 wet, optionally expandable to 12 dry, 12 wet

24 to 250 V DC 1 mS at 1 kC 0.05 mS at 20kC

Value ± 0.05%

± 1 digit

Coil current 3: Trip/ close coil current

1, 2, 5, 10 ,25 A DC

0.1 % of selected range

Value ± 0.5 % ± 1 digit (12 bit)



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Channels Configuration Range Resolution Accuracy

Voltage 3: Travel characteristics

0-5 V DC 1.2 mV Value ± 0.5%

± 1 digit (12 bit)

DCRM channels 1/2/3/6: each for resistance & test current as per configuration ordered

1000, 2000, 4000, 8000 µΩ

0.1% of selected range

Value ±1%

± 1 digit (12 bit)

Configurable channel

3: optional for analog signal inputs

0-5 V DC 1.2 mV Value ± 0.5%

± 1 digit (12 bit)

Advantages:

i. With the help of this instrument, it is possible to measure the length of arching contact when travel transducer is connected.

ii. During measurement 100 A DC is injected which ensures excellent accuracy and repeatability of results.

iii. It is a High speed V/I measurement.

iv. MCB protection saves battery from accidental short circuits.

v. It is a portable and user friendly instrument.



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3.3 CONTACT RESISTANCE MEASUREMENT 3.3.1 Contact Resistance Meter

Name of instrument Contact resistance meter

Application Contact resistance meter measures contact resistance of circuit breakers, isolators, bus-bars, welded joints etc. under the hostile electrostatic noise found in EHV line switch yard. Contact resistance meter directly measures micro-ohm values at 100 amps. DC under live switch yard condition.

Model (make) IRM 100 B(M/s Scope T&M Pvt. Ltd.) MOM 200A/ 600A (Programma Electric AB, Sweden)


Range 199.9 µΩ and 1999 µΩ

Resolution 0.1 µΩ and 1 µΩ

Accuracy Value ± 2% ± resolution

Current 100 A DC

Display Two, 3½ digit ½ inch LCD, for current and resistance value

Power 230 V AC ± 15%, 50 Hz ± 5%, 30 VA

Battery Instrument operation in input rechargeable battery (12V – 7AH maintenance free)

Weight 10kg approx.

Environment 0 to 50°C max. 95% RH Advantages:

i. This instrument injects 100 Amps DC to ensure reliable measurement in accordance with IEC 56.

ii. It is a battery as well as mains operated instrument.

iii. It displays contact resistance values direct in micro-ohms.



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3.4 TIME INTERVAL MEASUREMENT

3.4.1 Time Interval Meter

Name of instrument Time interval meter

Application Time interval meter measures and indicates close, open and C-O time of circuit breakers and interrupters.

Models (make) M3K SCOT (M/s Scope T&M Pvt. Ltd. Mumbai.)

TM 1600 (Programma Electric AB, Sweden)


Channels Three

Output 4 line 20 characteristic backlit LCDR 3232 port for downloading to PC.

Range 999 milliseconds maximum

Resolution 1 milli second

Accuracy Value ± 0.05 % ± resolution

Power 230 V AC ± 15 %, 50Hz ± 5%

Weight 11 kg approx.

Advantages:

i. It is suitable for working in EHV switchyard and ideal for field.

ii. This instrument can measure the timings in milli-seconds of three poles simultaneously.



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4.0 TESTING INSTRUMENTS FOR CURRENT TRANSFORMER

4.1 PARAMETERS TO BE MONITORED AND WHY

4.1.1 Excitation, Ratio and Polarity

Current transformer excitation test provides a variable voltage output and digital instrumentation for measuring the excitation voltage and excitation current those results as the voltage applied to the CT under test is increased. As the CT begins to saturate, a large increase in current will be detected for a small increase in voltage. The ratio test is performed by comparing a voltage applied to the secondary winding to the resulting voltage produced on the primary winding. Polarity of the CT under test is determined by special circuitry that divides the voltage applied to the secondary winding by either 10 or 100, depending on switch position, and then adds the results to the primary voltage. An increase in magnitude indicates correct polarity, and a decrease shows incorrect polarity.

4.1.2 Burden

Within the accuracy limits of the CT, a good CT should not have a noticeable change in ratio when a secondary burden is added. This is because the primary effect of additional burden on a good CT is a rise in the secondary voltage. If one or more turns of a CT are shorted, a substantial amount of the total available ampere- turns is diverted into the shunt path created by the short. Thus, the current to the circuit connected to the CT is less than the CTs total secondary current.



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4.2 CURRENT TRANSFORMER EXCITATION, RATIO AND POLAR ITY MEASUREMENT 4.2.1 Current Transformer Excitation, Ratio & Po larity Tester

Name of instrument Current transformer excitation, ratio & polarity tester

Application This instrument tests the excitation, ratio and polarity of current transformer using the voltage comparison method.

Model (make) CTER-91(Megger Limited)


Input 120 V, single phase, 50 Hz/ 60 Hz. 240 V, single phase, 50 Hz/ 60 Hz.

Output Continuously variable in four ranges 0 to 40 V at 1.5A 0 to 150 V at 1.5 A 0 to 600 V at 1.5 A 0 to 1000 V at 1.0 A

Instrumentation

Voltmeters Two 4½ - digit, auto ranging

Accuracy ± 0.25% of reading, ± 1digit for 1 to 1000V, ± 1% of reading, ± 1digit for 0.2 to 1V

Ammeter One 4½ digit

Accuracy ± 0.85% of reading, ± 1 digit

Weight 16.8 kg.

Advantages:

i. It provides a variable voltage output and precision instrumentation for testing single and multi-ratio CTs.

ii. All three tests excitation, ratio and polarity can be performed without changing any leads.

iii. It can test bushing CT, mounted inside transformer or switchgear.

iv. It has inbuilt overload and short- circuit protection.

v. It has a RUN/HOLD switch which freezes readings on instrument when switched to the HOLD position.

vi. A zero-start interlock is incorporated. This minimizes the possibility of energizing the CT under test with sudden high voltages.



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4.3 CURRENT TRANSFORMER BURDEN MEASUREMENT

4.3.1 Current Transformer Burden Ammeter

Name of instrument Current transformer burden ammeter

Application The current transformer burden ammeter is a rugged, portable instrument, designed to field test current transformer installation for

a. Short circuit secondary turns

b. Short circuited primary turns

c. Short circuited secondary wiring

d. High – resistance connection in the secondary circuit.

e. Grounding of secondary winding when mounted on a grounded structure.

f. Grounding of a normally under grounded wire.

Model (make) BA – 185 (Megger Limited)


Ammeter ranges 1.25, 2.5, 10 Amps

Burden 0.25, 0.5, 1, 2 & 4 ohms

Burden ratings (VA at nominal current of 5 amps)

6.25, 12.5, 25, 50 & 100 VA

Weight 1.1 kg

Advantages:

i. It is designed to ensure that the secondary of the CT under test will not be accidentally opened.

ii. It uses make-before-break construction for ammeter range and burden selector switch.

iii. The burdens are normally shorted out, but can be put in series with the ammeter by a spring-loaded momentary switch.



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5.0 TESTING INSTRUMENT FOR SURGE ARRESTOR 5.1 PARAMETERS TO BE MONITORED AND WHY 5.1.1 Leakage Current

Failure of surge arrester take place mainly due to ingress of moisture inside surge arrester and/or ageing of oxide blocks causing severe damages to surge arrester poles and also to the neighboring equipments. Monitoring of leakage current is required to measure the third harmonic resistive component (THRC) of surge arrester. It provides quick and reliable information about the health of the surge arrester in incipient stage and accordingly the corrective measures can be taken at right time to avoid subsequent failures.



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5.2 LEAKAGE CURRENT MEASUREMENT 5.2.1 Leakage Current Meter

Name of instrument Leakage current meter for surge arrester

Application This instrument is suitable for measurement and analysis of resistive leakage current of surge arrester in live switch yard condition without any need for shut down.

The system is based on the measurement of 3rd harmonic resistive current with compensation for harmonic in the system voltage.

Model LCM III ( M/s. Applid Techno Gurgaon,)

SA 302 ( M/s Scope T&M Pvt. Ltd., Mumbai.)

SCAR – 10( ISA srl, Italy)


Range Total leakage current 100 microA to 10mA

resistive leakage current 1 microA to 10mA

Field probe current 10 microA to 1mA

Resolution 1microA for both resistive & total currents

Accuracy ± 5% for both currents

Input External clamp – on CT, field probe, external PT (110 V AC)

Output Self – calibration output

Display 4 line x 20 character large backlit LCD.

Key board 5 keys

Measurement Total current, resistive current

Temperature In-built silicon, thermometer for compensation

Power 12V DC, 2.4AH. SLA rechargeable battery



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Battery charging 230V AC ± 15%, 50Hz ± 10%

Environment 0 to 5°C, 95% RH

Weight 7.5 kg approx.

Advantages:

i. It provides quick and reliable information about the heath of the surge arrester and

allows for storing of all the measurement data’s in the field.

ii. It measures following parameters & displays directly on LCD display

a. Total leakage current.

b. Third order harmonic current.

c. Resistance leakage current.

d. Correct value of resistive leakage current.

e. Waveform display



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6.0 TESTING INSTRUMENT FOR RELAYS 6.1 PERFORMANCE TESTS TO BE DONE ON RELAYS AND WHY

6.1.1 Primary Current Injection Test

Most of the electric supply protective systems are fed from CTs connected to the supply cable or bus-bar. Primary current injection test checks all the components of the protective system. A high test current, enough to cause the protection equipment to operate, is injected into the supply cable. Time taken for the protection relay to operate is then measured.

The primary current injection test is essential when commissioning new protection systems and after major repair and component replacement, since it tests the whole system. It will detect CTs connections with incorrect polarity or relays that have been set in the wrong sequence in differential systems.

6.1.2 Secondary Current Injection Test

Secondary current injection test checks the operation of the protective relay etc. but does not test the overall system including the CTs. A secondary injection test is easier since there is no need to break the primary circuit and it requires less current through the operating coil of the protective device. The time taken for the protection device to operate is then measured.



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6.2 PRIMARY CURRENT INJECTION TEST

6.2.1 Primary Current Injection Relay Test Set

Name of instrument Primary current injection test

Application Primary current injection test sets have two main applications. The first of these is the testing of complete relay protection system as well as the entire chain current transformer, conductors, connection points and circuit breakers etc. The second role of the primary current injection test set is to test the current transformer in a protection system.

Model (make) PCITS 2000/2,( Megger Limted.) ODEN A/AT,( Programma Electric AB, Sweden) T- 2000 (ISA srl, Italy)


Maximum current output AC

2000 A at 0 to 3V 1000A at 0 to 6v

Auxiliary voltage output AC

0 to 250 V, 2A 0 to 125v, 2A

Display Dat matrix LCS

Current 0 – 2000A, resolution 1A

Auxiliary voltage range 2 – 250 V, resolution 1 V

0 – 2A, resolution 0.01A

Accuracy ± 3% of reading, ± 2 digits

Timer 0 – 600 seconds, resolution 0.01 seconds

Temperature range 0°C to 40°C (operation)

- 20°C to +60°C (Storage)

Weight 61 kg (Approx.)



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Advantages:

i. Primary current injection tests the complete relay protection systems comprising the isolated high voltage conductor, CT, protection relay and the circuit breaker.

ii. Primary current injection tests the testing of the current transformer in a protection system.

iii. It is provided with built-in timer to record protection relay operation.

iv. As current level is maintained though out the test, circuit resistance may rise due to heating.



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6.3 SECONDARY CURRENT INJECTION TEST 6.3.1 Secondary Current Injection Relay Test Set

Name of instrument Secondary current injection relay test set

Application Secondary current injection test set checks the operation of the protective relays etc. but does not test the overall system including the current transformer.

A secondary injection test is easier since there is no need to break the primary circuit and it requires a less current through the operating coil of the protective device.

Model (make) T-1000, SVERKER,( M/s Scope T&M Pvt.Mumbai)

750/760, ( Programma Electric AB, Sweden)

T-1000 plus, (ISA srl, Italy)


Range 0.5A ∼ 10A

05 A ∼ 100A

Accuracy ± 0.5%

Output voltage 60 V ∼ 50V; 10V ∼ 8V

Power 500 VA (10A), 800 VA (100A)

Load time

Output 100 A, 50A < 50A

Time 750 sec, 3000 sec. continuous

Advantages:

i. A secondary current injection test is easier since there is no need of break the primary circuit.

ii. It can test relays and CT and it can be used as multi-meter also.

iii. It is easy to control and can also be controlled via external PC.

iv. It has an advance high power constant current source with pulse width modulation technology.



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7.0 CHECKING OF ELECTRICAL CONNECTIONS 7.1 LOOSE CONNECTIONS AND HIDDEN FAULTS CHECKING

Failure of electrical & mechanical devices is because of component failure or electrical loose connections. Failure such as overhead line problem, problem in electric connections, overheating, hidden faults and insulation defect etc results in thermal heating. Infrared thermal imaging camera can detect electrical hot spots on faulty equipment and hidden faults, when conducting routine survey of electrical system.

7.2 INFRARED THERMAL IMAGING CAMERA

Name of instrument Infrared thermal imaging camera

Application Thermal imaging infrared camera identifies electrical and mechanical problems like hot spots, heat development on loose connections etc. before they result in failures.

It is a non-contact device which detects infrared radiations and converts it into electronic signals. These signals are then processed to produce thermal image of the object.

Models (make) Flir T – 200 (FLIR Systems, Canada)

Ti45FT-20/54 (Fluke South East Asia Pte Ltd Singapore)


1. Temperature measurement range from – 20°C to 1200°C.

2. Temperature measurement accuracy of ± 2%; ± 2°C of reading

3. Image quality of 200 x 150 pixels

4. Thermal sensitivity of 0.1°C

5. IFOV of lens should be 2.18 mrad or less.

6. Spectral range of 7.5 to 13 µm



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7. Built in digital visual camera of 1.3 m pixels

8. Standard lens with FOV of 25° x 19°

9. Permissible relative humidity range 10% to 95% non-condensing

10 Operating & storage temperature range with all accessories in -15°C to 50°C & -40°C to 70°C respectively.

11. Software should have the feature to prepared report & can be saved in PDF format.

12. At least 3 palettes should be available with 2 color palettes; grey with white hot & grey with black hot etc.

13. LCD color display 3.5 should be available in camera.

14. Data can be stored in removable SD card with storage capacity of 1000 + images

15. Menu operation should be available via touch screen as well as via toggle button.

16. Auto focuses facility available in camera along with manual focus.

17. Focusable from 0.4mt. to infinity.

Advantages:

i. It helps to find out electrical hot spots and faulty equipments in incipient conditions. ii. It is an ideal means for professionals looking for safety and reliability when

conducting routine surveys of electrical systems, switchgear and electrical components.

iii. It is a light weight, comfortable and sensitive test instrument with touch screen, text features.



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8.0 TESTING INSTRUMENT FOR MEASURING EARTH RESISTAN CE 8.1 EARTH RESISTANCE

The object of an earthing system is to provide as nearly as possible a surface under and around a station, which shall be at a uniform potential and as nearly as zero or absolute earth potential as possible. The purpose is to ensure that generally all parts of the equipment, other than live parts are at earth potential. The attending personnel are at earth potential at all times.

The primary requirements of a good earthing system are:

• It protects men and material from injury or damage due to over voltage.

• It keeps the maximum voltage gradient along the surface inside and around the station within safe limits during earth faults.

• It stabilizes circuit potentials with respect to ground and limit the over all potential rise.

• It provides low impedance path to fault current to ensure prompt and consistent operation of protective devices during ground faults.

Earth resistance measurement is very essential to maintain low values of resistance under all weather conditions.



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8.2 EARTH RESISTANCE AND RESISTIVITY MEASUREMENT

8.2.1 Earth Resistance and Resistivity Meter

Name of instrument Earth resistance and resistivity meter

Application This instrument is suitable to measure earth systems in substations, industries, distribution networks etc. It is also suitable for soil resistivity measurements in order to optimize the earth systems projects.

Models (make) MRU – 103,( Sonel S.A Swidnica Poland) DET 4TC,( Megger Limited) EM-4055(M/s Megabras Industrial Eletronica Ltd. Brazil)


Noise Voltage measurement DC + AC

Range : 0 - 40V Resolution:– 1V Accuracy: ± (10% m.V + 1digit)

Earth resistance measurement

Range: 0.12Ω - 20.0 KΩ

Earth resistance measurement using clamp

Range: 0.00 – 9.99 Ω to 10.0 – 20.0 KΩ Accuracy : ± (8% mV – 2 digit)

Soil resistivity measurement

Range: 0.00 – 9.99 ΩM to 100 – 999 kΩM

Accuracy ± (2% mV + 2 digit) Advantages:

i. This instrument is portable and can be used in the field under severe weather conditions.

ii. This instrument can measure resistance using 2, 3 or 4 pole methods, automatic calculation and displays the resistance value in ohms.

iii. It has four ranges that are automatically selected, covering measurement requirements.

iv. This meter can be powered from NI-MH batteries or standard ‘C’ size batteries.

v. Measurements can be simplified using current clamps and the test results can be stored in the internal memory and print out can be taken with built-in printer.



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9.0 TESTING INSTRUMENTS FOR BATTERIES 9.1 PARAMETERS TO BE CHECKED AND WHY

Repeated recharging of a secondary battery can lead to battery deterioration and increase in its internal resistance. Problem can intensify when there is a short circuit in the internal cell leading to voltage drop, increase in internal resistance, overheating and complete battery malfunction. These problems can cause severe fires and other accidents. It is important and necessary to conduct battery testing to check the above defects periodically.

Following parameters can be checked to determine the health of the battery:

• Voltage

• Impedance

• Specific gravity

• Sulfation (relative to the amount of battery charge capacity degradation due to sulfation)

• Dryout (relative to the amount of battery charge capacity degradation due to dryout)



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9.2 BATTERY ANALYSIS 9.2.1 Electro Chemical Battery Analyser

Name of instrument Electro chemical battery analyser

Application Electro chemical battery analyser accurately measures health of lead acid battery (chemical and electrical) in terms of sulfation, dry out, voltage and impedance.

All four parameters can be measured simultaneously in a single measurement.

Models (make) Interrogator 4210 (M/s World Energy Labs Switzerland)

Hikoi battery Hi-tester 3554(M/s HIOKI E.E.Corporation Japan)


Voltage

Range 0 to 17 V DC

Resolution 10mV

Accuracy ± 0.5%

Repeatability ± 0.5%

Impedance

Measurement range 50 µΩ to 1Ω

Resolution 0.001 mΩ for all measurable impedance value.

Accuracy ± 1.0 % (for impedance > 1mΩ to 1Ω)

± 1.0 % (for impedance > 100 µΩ to mΩ)



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Amp–Hour capacity range for batteries under test

5 Ah to 2,000 Ah; specified performance range

1 Ah to 9,999 Ah, operating range

Sulfation

Range

Accuracy

0 to 100%

± 5%

Dryout

Range

Accuracy

0 to 100%

±5%

Cell terminal strap impedance (µΩ)

Measurement range

Resolution

Accuracy

50 µΩ to 1Ω

0.001mΩ

±1.0%

Specific Gravity Manual logging

Safety Feature

Over voltage auto reset breaker

Trigger point – 17VDC

Warning – 50VDC

Damage point – 600VDC max.

Advantages:

i. It can store large amount of data and auto hold and auto-data storage facility also available.

ii. It has ability to measure AC voltage and low resistance.

iii. It can memorize the value on the spot.

iv. It can enhance resistance against noise.



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10.0 TESTING INSTRUMENTS FOR WIRES/ CABLES 10.1 WIRE TRACER/ CABLE LOCATOR

It is very difficult and time consuming task to detect or trace a break in cable, cables in ceilings, walls, floors, underground cables, shield cables and short circuits locations. Cable locator is designed to locate above faults very easily.

The cables can be detected regardless whether they are live or not and transmitter operation mode can be automatically selected.

Name of instrument Cable/ Wire locator

Application This instrument can be used to trace wires in walls, locate breaks in cables and short circuits, associate electrical outlets with circuit breakers etc.

Models 2042,( M/s Fluke Corporation WA USA) LKZ – 700(( Sonel S.A Swidnica Poland,)


Transmitter output signal 125 kHz

External voltage detection - Voltage range

12 to 400 V

Frequency range 0 to 60 Hz

Display LCD with display of functions

External voltage detection Max., 400 V AC/DC

Pollution degree 2

Power supply 6 x 1.5V, (M/s Khandela Electronic Indore) IECLR 6(M/s. PCI Pvt Ltd New Delhi)

Power consumption Max. 40mA

Temperature range 0°C to 40°C, max. 80% humidity

Storage (-20 to + 60°C)

Weight 400 gms.

Advantages:

i. It has automatic and manual sensitivity adjustment features. ii. It can be used for residential as well as commercial applications. iii. It displays with bar graph along with audible detection. iv. It can locate faults in underground cables/ wires in three phase installations also.



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10.2 CABLE ROUTE TRACER

It is difficult to trace, locate and measure the depth of buried power cables which are neither having cable route markers nor their route diagram record etc. This instrument is designed to locate, trace and measure the depth of buried energized power cables. It consists a compact, all steel control box. It is attached to a precision-wound, swivel-mounted detecting coil.

Name of Instrument Cable Route Tracer

Application The cable route tracer locates, traces and measures the depth of buried energised power cables.

This instrument can also be used to locate grounded electrical faults on un-shielded cables, particularly in direct buried installations.

i. Horizontal For maximum deflection over the cable.

ii. Vertical For a null over the cable

iii. 450 angle For a null at a horizontal distance from the cable that is equivalent to the cable depth.

Model (make) Nil (Magger Limited)


Locates and traces energised power cables with supply of 50/60 Hz.

Three way swivel detector also measures cable depth.

Portable (weight only1.1 kg) and overall length is 26 inches only.

It can be used indefinitely with little fatigue.

Two sensitivity ranges enables tracing of cables as much as 8ft. (2.4m) deep.

Battery 9-volt transistor type.



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Advantages:

i. It has fully transistorized amplifier with 10 turn gain control for wide adjustment range.

ii. It is not affected by telephone lines, gas or water pipes, steel reinforcing or metallic conduit.

iii. It responds current flowing in the cable, even in the metallic conduit.

iv. It has special feature of battery test circuit which provides upto 150 hours of operation.



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11.0 TESTING INSTRUMENTS FOR OVER HEAD EQUIPMENT 11.1 CONTACT WIRE SPARK CHECKING

Sparking occurs when there is loss of contact between the pantograph and the contact wire. The spark is developed in contact wire due to a kink in contact wire. It is important to attend the kink roughened surface of the contact wire to avoid further rapid deterioration, with successive passage of pantographs resulting in reduced life of contact wire.

It is necessary to carry out periodic tests to detect points at which contact between the contact wire and pantograph is unsatisfactory resulting in sparking. Current collection shall be carried out during night time for better results.

11.1.1 OLIVIR-G Plus

The OLIVIR-G Plus is developed to assist Over Head Equipment (OHE) spark detection using a video camera. The hardware units consist of a GPS receiver which track the current position of the locomotive in which the ‘OLIVIR-G plus’ is mounted.

The OLIVIR mate RT software supplied with the unit identities sparks in real time

and save them as images with locations, at the same time continuous video film is also recorded in hard drive. These images can be analyzed to recognize the type of spark (mega pixel) with their locations.

Name of Instrument Olivir – ‘G’ plus Application The OLIVIR-G Plus is developed to observe OHE (Contact

wire) spark detection using the video camera. The hardware units consist of a GPS receiver which track the current position of the locomotive in which the OLIVIR is mounted.

OLIVIR-G Plus is generate two types of reports:

i. Graphical Report

ii. Text Report

Model (make) OLIVIR – G plus(M/s Total solution, Bhopal)



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Accessories:

i. Focus light operated at 110V AC/DC supply.

ii. Camera and light

iii. GPS antenna

iv. Processing & login unit

v. GPS unit

vi. Serial cable

vii. Battery charger

viii. Track feature collection unit

Advantages:

i. It can show total number of images recorded during current collection test.

ii. The category of spark can be adjusted as per customer requirement.

iii. It gives the correct position of spark with its location.

iv. The size of spark value can be adjusted during current collection.

v. It automatically saves all recorded data in the laptop datewise.



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11.2 CONTACT WIRE HEIGHT & STAGGER MEASUREMENT

Any change in alignment due to slewing of tracks will affect the setting distance and the stagger of the contact wire. Change in rail level due to variation in ballast cushion or packing down of the track will also result in change in contact wire height.

Though provision exists in the cantilever assembly for adjustments of the stagger and height, such adjustments are not to be made unless absolutely necessary. It is best to maintain the position of OHE and tracks as in the SEDs.

11.2.1 Rail Rod Ultrasonic Height & Stagger Gauge

Rail Rod Ultrasonic Height & Stagger Gauge is used for measurement of height of

contact wire and catenary wire without power block both on meter and broad gauge tracks.

Name of instrument Rail Rod Ultrasonic Height & Stagger Gauge

Application Rail Rod Ultrasonic Height & Stagger Gauge is use for measurement of height of contact wire & catenary wire on horizontally track gauge variable 1.0 mtr. to 1.7 mtr.

Model (make) Rail rod – ABT 4420 (ABTUS Limited, Haverhill, Suffolk UK)


Display menu

i. contact wire ii. support cable iii. track width iv. sample size v. memory vi. base height vii. extended blanking

1 or 2 1 or 2( 1+1) Vertically 1.00 – 1.800 1 or 10( 1st Faster) standard or auto 0 to 1.000m( use on rail) 0 to 8.000m

Temperature Automatic

Cant/ gradient Measurement option available

Memory Auto

Display Two wire stagger

Number of measurements

Ten

Advantages: i. It can measure three wires vertically or two wires horizontally. ii. It is a compact & portable system (weight around 3.5 kg) hence suitable for single hand

use. iii. It can take measurement at cant/gradient locations.



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11.3 LIVE LINE CONTACT WIRE WEAR MONITORING

Following locations are generally prone to higher wear rate of contact wire:

• Stop Signal

• FOB/ ROB

• MEMU Locations

• Starter signal

It is therefore, becomes pertinent to monitor diameter of contact wire continuously at these locations. Diameter of new contact wire is 12.24 mm & condemning limit for main line is 8.25 mm. Present system over Indian Railways is checking diameter at one location per km. once a year during Tower Wagon checking.

One location per km. & that to be checked once in a year does not appear adequate since it is observed that new locations with dia less than 9 mm crop up at intermediate location and during intermediate time.

11.3.1 25 kV Live Line Contact Wire Wear Monitoring

To have better & continuous monitoring of contact wire wear Jig has been developed which gives measurement of contact wire dia at eye level without need of power block.

Name of instrument Contact Wire Wear Measuring Jig.

Application Continuous monitoring of contact wire diameter at eye level without power block.

Model (make) Nil

Developed by Sr. D.E.E.(TRD), Western Railway, Vadodara Gujarat


Material High insulated fiber glass epoxy Telescopic rod

(Jaw on top & Vernier calipers at eye level)

Length 5.15 m

Diameter of pipe 39mm outer, 30mm inner

Weight 5 kg

Electrical Type tested at 100 kV at ERDA BRC and capable with constant high voltage up to 30 kV perfect in wet condition water absorption is only 0.2 %

Advantages:

i. The contact wire locations having higher wear rate can be monitored more frequently.

ii. The number of locations to be checked per km. can also be increased.

iii. It can help in better monitoring of health of contact wire and consequent reduction in contact wire parting cases.



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11.4 LIVE LINE INSULATOR CLEANING

The OHE insulators require regular cleaning for ensuring un-interrupted traction supply. The periodicity of cleaning varies from area to area depending upon pollution level, proximity to sea etc. Where pollution is heavy, the cleaning has to be done more frequently. This cleaning is essential as the insulators are affected by dust/ smoke particles, industry/ chemicals deposits, accumulation of coal/ cement particles etc. which form conducting layers on porcelain thereby causing CB tripping during night hours/ foggy weather/ drizzling. The insulators in light/ non- polluted zone are cleaned twice in a year i.e pre- monsoon & pre- winter.

To overcome the problem of power block at aforesaid locations, a “Live Line Insulator Cleaning Jig” has been developed by Sr. D.E.E. (TRD),Western Railway, Vadodara (Gujarat)

11.4.1 Live Line Insulator Cleaning Jig

The jig consists of light weight “Two Insulated Rod”( Each rod comprising of 2 to3 detachable sections of 1.85 mt / 2.0 mt length each with push button locking arrangement) provided with cotton pad on top. The cotton pad is fixed on one end to first to rod & clamped to other rod after inserting on insulator through hook arrangement.

Name of Instrument Live Line Insulator Cleaning Jig

Application With the increasing trend of traffic on Railway system, the construction of power block is likely to worsen further in near future; resulting insulator cleaning will adversely affect reliability of OHE supply causing traffic dislocations. To overcome the problem of power block an insulator cleaning jig has been developed. The jig consists of light weight two insulated. Rods provided with cotton pad on top & clamped to other. Rod after inserting on insulator through hook arrangement.

Model (make) Nil Developed by Sr. D.E.E.(TRD), Western Railway, Vadodara Gujarat


i. Material Highly insulated fiber glass epoxy telescopic rod.

ii. Assembled length 6.0 (3 positions of 2.0m length two rods)

iii. Diameter of rod 39mm outer, 30mm inner

iv. Weight 6.0 kg

v. Electrical specification

Type tested at 100 kV at ERDA BRC and capable to withstand high voltage up to 30kV feet/ per ft. in wet condition water absorption is only 0.2%

vi. Cotton pad 2 feet long and 5 inch wide pad made of woolen cloth & spunge material.

Advantages:

i. It can save wastage of manpower for discharge Rod/ Power block/ E-socket/ Ladder etc.

ii. It can increase productivity.

iii. It gives better quality of insulator cleaning/ resultant reduction in CB transient trippings.



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ANNEXURE – I SUPPLIERS ADDRESSES:

S.No. Address Contact No.

1. M/s Scope T&M Pvt.Ltd., 12, Ganesh Apartment, Ist Floor, 376, L.J. road, Mahim, Mumbai – 400 016

Phone : 022 – 24442129/ 24442163 Fax : 022 – 2444 0720 e-mail : [email protected] Website : www.scopetnm.com

2. M/s Khandela Electronika Khandela House, 24-Gulmohar colony, Indore – 452018

Phone : 0731 – 4020081, 4020082 Fax : 0731 – 4020083 e-mail : [email protected] Website : www.khandela.com

3. M/s M-Tekpro Engineering Pvt. Ltd. B-229, LGF, Greater Kailash – 1 New Delhi – 110 048

Phone : 011 – 46173333 Fax : 011 – 1141825662 e-mail : [email protected] Website : www.mtekpro.net

4. M/s PCILtd., Prime Group Building,,11/5B, Pusa Road,New Delhi-110005

Phone : 011-41 888 999, 41 888 888 Fax : 0 11 25755815, 25821623 e-mail : [email protected] & [email protected] Website: www.primegroupindia.com

5. M/s SIVANANDA ELECTRONICS Deepaks Mahal, Lam Road, DEVLALI – 422 401, Nasik -(Maharastra).

Phone :0253– 2491423/ 2491504/2491816 Fax : 0253 – 2492291 e-mail : [email protected]

6. M/s Dakshin Lab Agencies

Ashwini Complex, First floor 6th main, LIC Colony New Thippasandra Bangalore – 560075

Ph no 080- 25291401, 25293599

(mob) 09845205110

E mail: [email protected]

Website : www.dakshinlab.com

7. M/s. Applied Techno Product Pvt. Ltd. Plot no. 85, sector 44, Industrial area, Gurgaon -122002(HARYANA)

Phone: 0124- 4288186 /7 / 8, Fax : 0124- 4288189, e- mail : [email protected], Website : www.atplonline net

8. M/s SAM International Pvt. Ltd.

158/160, Narayan Dhuru Street,

3rd Floor, Mumbai – 400 003.

Phone No. 022 – 23432037, 66370035 Fax: 022 – 23434773 e- mail : [email protected] Website : www.samint.in



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If you have any suggestions and any specific Comments please write to us.

Contact person : Director (Elect.) Postal Address : Indian railways

Centre for Advanced Maintenance technology, Maharajpur, Gwalior. Pin code – 474 005

Phone : 0751 – 2470740

0751 – 2470803 Fax : 0751 - 2470841

To upgrade maintenance technologies and methodologies and achieve improvement in productivity, performance of all Railway assets and manpower which inter-alia would cover reliability, availability, utilisation and efficiency.

OUR OBJECTIVE

Documents

HANDBOOK ON TESTING INSTRUMENTS REQUIRED...2.2 winding resistance measurement 04 2.3 winding insulation resistance measurement 05 2.4 capacitance & tan delta measurement 06 2.5 transformer