specification no. ti/spc/psi/isoltr/0130 ministry of...

DRAFT SPECIFICATION No. TI/SPC/PSI/ISOLTR/0130

RESEARCH DESIGNS AND STANDARDS ORGANISATION

Effective

From 21.03.2013

TECHNICAL SPECIFICATION for

25kV/72.5KV/123KV/145KV/245KV ac Single Pole , Double Pole & Triple Pole

Motorized/ Manual OPERATED ISOLATORS

FOR RAILWAYS ac TRACTION SUB-STATIONS

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SPECIFICATION No. TI/SPC/PSI/ISOLTR/0130

GOVERNMENT OF INDIA

MINISTRY OF RAILWAYS

Technical Specification

for

i. 25KV ii. 66KV iii. 123KV

iv. 145KV v. 245 KV

Motorized/Manual operated Isolators

For Railway Electric Traction

RESEARCH DESIGNS AND STANDARDS ORGANIZATION

GOVERNMENT OF INDIA

MINISTRY OF RAILWAYS

LUCKNOW - 226 01



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INDEX

Clause Description

1.0 Scope

2.0 Climatic, Environmental & operating condition

3.0 List of related specifications

4.0 Rating, name plate details and other information

5.0 Design and constructional features

6.0 Locking

7.0 Earth contact assembly

8.0 Arcing horn

9.0.9.1,9.2,9.3 Motor, Gear, Space heater, Terminal bock and Wiring

10.0 Test

11.0 Test Method

12.0 Revalidation of type tests

13.0 Bulk Manufacturing

14.0 Technical data and drawing

15.0 Installation, Testing and Commissioning

16.0 Clause wise conformity, deviations etc.

17.0 Warranty

18.0 Training of Indian Railway’s engineers

19.0

Packing and Dispatch

Annexure-A SCHEDULE OF GUARANTED PERFORMNCE DATA

TECHNICAL AND OTHER PARTICULARS FOR ISOLAOR.

Annexure-B following information shall be furnished by the manufacturer /supplier:

Annexure-C Definition

Annexure-D General arrangement of motorized isolator



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1. SCOPE

1.1 This specification applies to single pole double pole & triple pole

motorized/manual operated isolators with earthling switch/without earthling

switch as specified by purchases in the particular tender for outdoor use in

25kV ac 50 Hz single phase/2x25kV AT Feeding System for overhead

equipment (OHE), Traction Substations and Switching Stations. The

Specification also applies to the operating mechanism of the Isolator and

Earthling Switch. The Isolator shall be mounted on a mast/structure as

required. The operation of isolators and supply of battery charger through a

two core cable shall be possible from a remote location at more than 500 m

.The status of isolators i.e. whether Close or Open shall be available at the

station master chamber. This Specification supersedes following Specification:-

Sl.No Specification No. Description

1. ETI/PSI/41(1/73) 110kV,Double Pole and Triple Pole Isolators


3. ETI/PSI/20A(6/79) 132kV,Earthing Blade Assembly for Double

Pole and Triple Pole Isolators

4. ETI/PSI/20B(7/79) 132kv,Double Pole and Triple Pole Motor

Operated Isolators


6. ETI/PSI/50A(8/79) 66kV,Double Pole and Triple Pole Isolators

7. ETI/PSI/50B(4/80) 66kV,Double Pole and Triple Pole Motor

Operated Isolators


9. ETI/PSI/122(3/89) 245kV/145kV/123kV/72.5kV Double Pole

and Triple Pole Isolators

10. ETI/PSI/133(8/89) 25kV,ac Double Isolators for 2x25kV AT

Feeding System



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11. ETI/OHE/16(1/94) 25kV,ac Single Pole and Double Pole

Isolators

12. TI/SPC/PSI/ISOLTR/1060.

25kV,ac Single Pole and Double Pole

Motorized Isolators

1.2 Scope of supply

The isolator shall be complete with all parts, fittings and accessories including mounting frame work, insulators, operating rod, operating mechanism box, battery, battery charger remote control box along with OPEN/CLOSE

indication, cable size, insulators, motor operating mechanism and battery and charger necessary for its efficient operation. All such parts, fittings and

accessories except cables shall be deemed to be within the scope of this specification, whether specifically mentioned or not. The isolator, single, double and triple pole, shall be supplied fully assembled on a suitable rigid

frame. For double/triple pole isolators, the cross channels for mounting, shall also form part of supply and for type 1 A (SP) 24V, 40AH, battery& battery

charger shall also part of supply. 1.3 The earthling switch (wherever provided) shall be of the manually operated

type, complete with all parts, fittings and accessories including mounting attachment, operating rod/operating mechanism box etc. necessary for their

efficient operation.

2.0 Climatic, Environmental & operating condition 2.1 The isolator is intended to be used as outdoor line sectioning switches .the

isolator shall be used in normally polluted atmosphere, subject to dust, smoke and effluents from chemical plants. It may also be used in coastal areas.

2.2 Environmental Conditions

S. No

Parameters Value

1. Maximum ambient air temperature

550 C

2. Minimum temperature of air in shade

-5 0 C



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3. Maximum relative humidity 100%

4. Annual rainfall Ranging between

1750 mm & 6250 mm

5. Number of thunderstorm days per annum

85 (Max)

6. Number of dust storm days per annum

35 (Max)

7. Number of rainy days per annum 120 (Max)

8. Maximum basic wind pressure 200 kgf/m2

9. Altitude Not exceeding1000 m

10. Pollution level Very Heavy as per IEC 815-1986 & IS 13134-1992

2.3 The isolator shall be subjected to vibrations on account of trains running on

nearby railway tracks. The amplitude of these vibrations, which occur with rapidly varying time periods in the range of 15 to 70 ms, lies in the range of

30 to 150 microns with the instances peak going up to 350 microns. 3.0 List of related specifications

3.1 The isolator and earthling switch shall, unless otherwise specified herein,

conform to the latest version of the Indian Standards. Specifications/IEC recommendations/Research designs and Standards Organization (RDSO) specifications as indicated below and the Indian Electricity Rules, wherever

applicable:

S.No Standard no Description

1. IS:1248 Electrical indicating instruments

2. 1570(Pt.II) Carbon steels (unalloyed steels)

3. IS:1651 Specification for stationary cell & batteries, leadacid type (with tubular +ve plates)

4. IS:1652 Specification for stationary cells & batteries, .lead – acid type (with plante +ve plates)

5. IS: 2071

(pt. I & II)

General definitions and test requirements and test

procedures

6. IS: 2108 Black heart malleable iron castings

7. IS: 2419 Electrical indicating instruments

8. IS: 2544 Porcelain post insulators for systems with nominal



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voltage greater than 1000 volts

.9 IS: 4540 Rectifier assemblies & equipments

10. IS: 5561 Electric power connectors

11. IS: 6619 Rectifier assemblies & equipments

12. IS: 7608 Phosphor bronze wires (for general engineering

purposes)

13. IS: 7906 Helical compression springs

14. IS: 8828 Miniature circuit breaker

15. IS: 9921(Pt. I, II, III & IV)

Alternating disconnectors (Isolators) and earthling switches for voltage above 1000V

16. IEC:60129 Alternating current disconnections (Isolators) and earthling switches

17. ETI/OHE/13(4/84) Specification for hot dip zinc coating on steel masts (rolled and fabricated) tubes and fittings used on

25kV ac OHE)

18. ETI/OHE/18(4/84) Specification for steel and stainless steel bolts,

nuts and washers.

19. ETI/OHE/64 64 Specification for Solid Core Cylindrical post

insulators for system with nominal voltages of 220kV, 132kV, 110kV & 66kV

3.2 Any deviation from this specification proposed by the tenderer, intended to improve upon the performance, utility and efficiency of the equipment will be

given due consideration, provided full particulars of the deviation with justification thereof are furnished .In such a case, the tenderer shall quote

accordingly to this specification and deviation, if any, proposed by him shall be quoted as an alternative(s).

3.3 In case of any contradiction between the provisions of Indian Standards Specification/recommendations of the IEC and this specification, the later shall

prevail.



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4.0 Rating name plate details and other information 4.1(a)

Motor/ Manual Operated,

Horizontally Mounted on pole,

Vertical Break Type and

suitable for out door

Type 3 Motor Operated/Manual

DP,TP,Horizontal Mounted on pole,

Horizontal Break Type and suitable

for out door

SI.

No

Particulars NOMINAL SYSTEM VOLTAGE (KV)

25KV 66 KV 100/

110KV

132KV 220KV

1 2 3 4 5 6 7 8 9

1 Type of

Isolators

Type 1A

(SP)/

Type 1B

(DP)

Type II

(SP/DP)

TypeIII

(SP/DP)

2 Rated

Current

1250 A

1600A/

2000A

3150A 1250 A 1600 A 1600 A 2000 A

3 No of Poles 1/2 1(or)2 1(or)2 2(or)3 2(or)3 2(or)3 2(or)3

1 2 3 4 5 6 7 8 9

4 Nominal

System

Voltage

25KV 25KV 25KV 72.5KV 123KV 145KV 245KV

5 Rated

Frequency

50Hz

+/- 3%

50Hz

+/- 3%

50Hz

+/- 3%

50Hz

+/- 3%

50Hz

+/- 3%

50Hz

+/- 3%

50Hz

+/- 3%

6 Isolating

Distance in

Air(min)

500 mm 500 mm 500 mm 1200

mm

1800

Mm

1800

mm

2800

mm

7 Distance

between

pole centers

NA/DP

1000

mm-DP

NA/DP

1500

mm-DP

NA/DP

1500-

mm-DP

2000

mm

3000

mm

3000

mm

4500

mm

8 a)Rated one

minute

power

frequency

wet

withstand

voltage

(i) To earth

and between

poles

95 KV

(rms)

95 KV

(rms)

95 KV

(rms)

140 kV

(rms)

230kV

(rms)

275kV

(rms)

460kV

(rms)



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(ii)Across

isolating

distance

110 KV

(rms)

110 KV

(rms)

110 KV

(rms)

160 kV

(rms)

265kv

(rms)

315 kV

(rms)

530 kV

(rms)

b) Lightning

impulse

(1.2/50

micro-

second) with

stand

voltage

(i) To earth

and between

poles

250 KV

(peak)

250 KV

(peak)

250 KV

(peak)

350kV

(Peak)

550 kV

(Peak)

650kVp 1050

kV

(Peak)

(ii) Across

isolating

distance

290 KV

(Peak)

290 KV

(Peak)

290 KV

(Peak)

375kV

(Peak)

630 kV

(Peak)

750 kV

(Peak)

1200kV

(Peak)

9 Rated short

time with

stand

current. for

Three

second

(Both main

& earthling

switch)

20 KA

(rms)

20 KA

(rms)

50 KA

(rms)

31.5kA

(rms)

40 kA

(rms)

40 kA

(rms)

40 kA

(rms)

10 Rated peak

with stand

current both

for main and

earthling

switch

50 KA 50 KA 125 KA 100 KA 100 KA 100 KA 100 KA

11 Temperature

Rise

Name of parts The temperature of any parts of an

isolator shall not exceed the

maximum temperature rise given

below under the conditions specified

in the test clauses- 10.5

Temperature

in degree 0C

Temperature rise at

an ambient

Temperature not

exceeding 40 0C

a)Copper contacts

i) Bare copper or tinned Al

alloy

ii) Silver faced copper, copper

alloy or alloy

75

105

35

65



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b)Terminals of isolators to be

connected to external

conductors by screws or bolts

i) Bare

ii) Silver- faced

90

105

50

65

C) Metal parts acting as The temperature shall not reach a

value where the elasticity of the

materials is impaired. For pure

copper, this implies a temperature

limit of 75 0C

Note: - When applying the

temperature rise of 65 0C, care

should be taken to ensure that no

damage is caused to the surrounding

insulating material.

The quality of silver facing

shall be such that a layer of

silver remains at the points of

contact after the mechanical

endurance test. Otherwise,

the contacts shall be regarded

as bare.

The values of temperature and

temperature rise are valid

whether or not the conductor

connected to the terminals is

silver faced.

4.1 (b)

1. Rated current Type-1 A (SP)- 1250 A(For use in Station and siding)

Type 1 B (DP)1250 A (For use in OHE at SP,SSP) Type-2 - 1600 A/2000A( SP/DP)

(used at feeding post & traction sub-station)

Type-3 -3150A (Used in OHE on traction substation with

30 MVA transformers in Mumbai suburban section)



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2. Operating Mechanism (i)Isolator for Station and sidings Type-1 ‘A’- (1250A) = 24 Volt, 40 Ah

battery connected with battery charger for charging shall be provided for 24 V DC

motor drive operating mechanism .Power supply shall be 240 volt AC nominal with variation from 170 to 270 Volts .24V

,40AH Battery & Battery charger with box supplied by manufacturer

(ii) Isolators for SP & SSP Type-1 ‘B’ (1250 A) = Operating

mechanism shall be driven by 110 V DC motor fed by existing 110 Volt, 40 Ah

battery available at SP & SSP ,locations. (iii) Type-2 A (1600) = Operating

mechanism shall be driven by 110 V Dc motor fed by existing 110 Volt battery

available at Sub-stations /posts. (iv) Type- 3 (3150 A) = Operating

mechanism shall be driven by 110 V DC motor fed by existing 110 Volt, battery

available at Sub-stations/ posts.

3. Battery Constructional features / technical

requirements shall be in accordance to RDSO Spec No. RDSO/PE/SPEC/TL/0040-2003(Rev-0) - Low maintenance lead acid

battery.

4. Battery Charger Constructional features/ technical

requirements shall be in accordance to RDSO Spec No. RDSO/PE/SPEC/AC/0008

– August – 2004 (Rev- 1)

Battery and Battery Charger shall be procured from RDSO approved sources only for fitment on the isolator. Type tests once conducted by RDSO, user railways or railway’s authorized inspecting organization will be valid and need

not be repeated during this period.



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5.0 Design and constructional features

5.1 Operating mechanism The isolator motor shall be suitable for operation with 24 V DC for type I A and

110V DC for type II & III. The voltage at the battery terminals may vary between 110% and 85% of the normal value. The voltage at the isolator motor

terminals is likely to be less than 85% of the normal value of 24 V or 110V due to voltage drop in control cable. The isolator shall be able to operate manually in case of failure of motor circuit. Once the closing /opening operation has been

initiated by driving motor up to the snap actuation point, closing/opening will be completed automatically with snap action even if there is a failure of 24 V or

110 V dc supply at this point. The motor drive unit shall be installed in a weather and corrosion proof,

adequately ventilated cubicle made of sheet steel not less than 2 mm thick with adequate stiffeners to prevent deformation during transit and handling. The

cubicle shall have a sloping roof. To prevent condensation of moisture in the cubicle, metal clad space heater, controlled by an associated thermostat and switch, shall be provided.

The top of the cubicle shall be at a height of about 1.5 m from the rail level.

The cubicle shall be so positioned that the hinge of the operating handle - for manual operation - is at a height of about 1.1 m from the rail level.

The isolator and its control circuit shall be designed for operation from the remote control center (RCC) by the traction power controller (TPC) as well as

from the isolator cubicle. Local/remote spring-loaded switch as well as necessary terminations for tele-signals and telecommands from and to the

isolator- for operation from the RCC- shall therefore be provided in the isolator cubicle. The isolator cubicle shall be provided with motor protection relays.

The operating mechanism shall be such that it is possible to fasten the base to which the operating handle is attached, to either of the two mutually

perpendicular vertical faces of the supporting structure on which the isolator is mounted. The operating handle of the isolator shall be so designed as to work in the vertical plane. The isolator shall close when the handle is moved

upwards. The free end of moving contact shall be fully housed in the fixed contact when the handle is moved fully upward in which position the isolator

can be locked. The design of the single pole isolator shall be such as to permit coupling of isolators for gang operation from a single operating handle. Not more than two single pole isolators are required to be coupled. Suitable “OFF”



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and “ON” plates shall be provided on the operating handle to indicate when the isolator is open and closed respectively.

All poles of the isolator shall operate simultaneously. Provision shall be made for adjustments, if required, for the proper alignment of the pole after

mounting. All movable joints shall be provided with brass bushes/ bearings, which shall be entirely maintenance free. The blades of the isolator shall be of

electrolytic high conductivity copper tubes of adequate strength and cross section to IS: 191 (Part V) – 1980 to withstand thermal and bending stresses particularly under short circuit fault conditions. Flexible braided copper, where

used, shall have corrosion resistant coating such as tinning or silvering. The connection between the flexible braid and rotating and fixed parts shall be by

means of not less than two bolts to prevent any tendency of rotation. For reasons of safety, the isolator should be so designed that no dangerous leakage current can pass from the terminals of one side to any of the terminals of the

other side.

When installed, the isolator shall be able to bear on terminals the total forces (including wind load and electro dynamic forces on the attached conductors) related to the application and rating without impairing their reliability or current

carrying capacity. The isolator shall be constructed so as to permit it being locked both in the open as well as closed positions. It shall not be possible to

lock the isolator in any intermediate position. The fixed contacts of isolator shall be of extruded, rolled or drawn copper strips. The contacts shall be spring-loaded. Only non-ferrous or stainless steel components shall be used in the

contact assembly. The springs used in the contact assembly of the isolator shall be of phosphor bronze conforming to IS: 7608-1975. To avoid current passing

through the springs, nylon strip of suitable size shall be provided for insulation. The characteristics of the springs shall conform to IS: 7906 (Pt. II)-1976 and

their mechanical properties shall not be affected in any manner on account of rise in temperature during operation. Bolts, nuts locknuts and other fasteners of 12 mm dia and less shall be of stainless steel. Fasteners of higher size may be

made of hot dip galvanized obtained from Central Organization for Railway Electrification, Allahabad. The fasteners shall confirm to RDSO specification No.

ETI/OHE/18. The frame (isolator mounting channel) of each isolator shall be provided with an ear thing terminal for connecting to an ear thing conductor having clamping screws, suitable for earth fault conditions. The diameter of the

clamping screws shall be not less than 12 mm. The connecting point shall be marked with “Earth” ( ) symbol. The Operating pipe shall not have any joint

and shall be supplied with four guides unless otherwise specified in the purchase order. The operating pipe shall be obtained only from approve manufacturers, a list of which may be obtained from CORE/ ALD .All malleable



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cast iron parts shall be of black heart malleable cast iron grade BM- 340 conforming to IS: 2108-1977.Allferrous parts shall be hot dip galvanized in

accordance with specification No. ETI/OHE/13(4/84).The isolator shall be provided with a terminal pad at each end as shown in Appendix C attached. The terminal pad shall have few holes as indicated for being connected to a terminal

connector.

The general arrangement of the isolator shall be as shown in Appendix C. The essential dimensions are also indicated in the Appendix C.

5.2 Steel structure

The support and framework shall be designed for a wind pressure of 200 kgf/m2 acting on 150 %of the projected area in addition to all other loads. During the opening and operations of the isolator there shall be no shock. There

shall also not be a backlash tending to open the isolator after closing, due to the jerk, if any. The mounting arrangement and the operating mechanism shall

be such that with the isolators mounted in the working position, the hinge pin of the operating handle is at a height of 1.1m from ground level. The height of base of the rigid frame would vary, depending on the type of mast/ or structure

on which the isolator is mounted. The heights for typical masts/ structures are given below:

Location Height of isolator mounting channel from ground level in mm

SP DP

RSJ/BFB mast 8310 8160

RSJ with super mast 9425 9275

R Portal 9535 9385

N Portal 9485 9335

O Portal 9585 9435

Two track cantilever 9560 9410

SS,SSP,SP,FP 3262 ------

5425 5525

(When bus bar height is 5968mm)

The isolator shall be supplied with operating pipe in exact length for the particular mast/ structure, the length being obtained from the purchaser for

each type of mast/ structure.



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5.3 Insulators

The support and operating rod insulators shall be of solid core/composite type in accordance with the latest specification of RDSO viz No. ETI/OHE/15 (9.91) with A&C Slip No.1 to 6 or composite type as per RDSO

Spec.No.TI/SPC/OHE/INSCOM/0991and shall be procured, if included in the order, only from the approved manufacturers as per drawings approved by

RDSO.

5.4 Isolator

5.1.1 The isolator shall be robust in construction and so engineered as to ensure

operation at all times.

5.1.2 The moving blades shall rotate through 900 from their fully closed position to

fully open position, so that the break is distinct and clearly visible from ground level

5.1.3 The isolator shall be designed to minimize the shock during opening and closing

operations, and shall not have a backlash tending to open the isolator after

closing due to jerk. The isolator shall be so designed that it can come off its open/close position by vibrations, shocks or any other means except when

specifically operated with the help of its operating handle. 5.1.4 The rotating blade (s) on the moving poles shall operate simultaneously. An

arrangement for necessary adjustment to achieve this feature shall be provided.

5.1.5 Main contacts

i The isolator shall have heavy-duty self-aligning and high-pressure contacts of modern design.

ii The contacts of the isolator shall be in the form of reverse loop so that

during passage of short circuit current they exert additional pressure on the moving contacts.

iii The blades of the isolator shall be of rotating type at its longitudinal axis by the turn and twist mechanism provided in the moving contact assembly.

iv The moving and fixed contact assemblies shall be so designed as to ensure

a) Electro dynamic forces with stand ability during shat circuit without risk of

dislodging of moving contact firm the fixed contact;



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b) thermal with stand ability during short circuits; c) Constant contact pressure even when the live parts of the insulator stacks

are subjected to tensile stress due to liner expansion of connected bus bar conductor, either because of temperature variation or strong wides.

d) Wiping and self-cleaning action during closing and opening, and

e) Self- aligning ensuring smooth closing of the isolator.

5.1.6 Earthling switch 1) The ear thing switch shall be manually/Motor operated. 2) The moving contact shall be made of electrolytic high-conductivity

copper of adequacy strength to with stand all thermal and bending stresses at the time of short circuits.

3) The fixed contacts shall be identical to the main isolator fixed contacts expect for silver plating.

4) The ear thing of the moving contact shall be affected by flexible copper

braids of adequate cross-section safely carry the short circuit current specified clause 4.1(a) above.

5) The earthling switch for all poles of the isolator shall be mounted on the same shaft and operated by a single and common operating handle, which shall be distinct and separate from that used for operating the

isolator. 6) The moving contacts of the ear thing switch shall close home

simultaneously in the fixed contacts. 7) Suitable counterweights shall be provided in the operating mechanism of

the earthling switch, so that while opening the moving contacts it does

not come to rest with a jerk.

5.1.7 Terminal pad and terminal connectors

5.1.7.1 The isolator shall be provided with hard–drawn, extruded or rolled electrolytic copper terminal pad on either end to be connected to the terminal connectors.

5.1.7.2. The terminal connectors shall be of bimetallic type to prevent electrolytic

corrosion and shall conform to RDSO’s standard drawings, which are enclosed with this specification.

5.1.8 Material for various components

5.1.8.1 The blades of the isolator shall be of electrolytic high conductivity copper with the ends silver-plated (minimum thickness 10 microns) and of



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adequate strength to withstand all thermal and bending stresses, particularly, at the time of passage of short circuit currents.

5.1.8.2 The fixed contacts of the isolator shall be made out of copper, extruded,

rolled or drawn. They shall be silver- plated (minimum thickness 10

microns)

5.1.8.3 Bolts, nuts and other fasteners of 12 mm dia or less shall be of stainless steel. Higher sizes of fasteners may be of hot-dip galvanized steel to RDSO’s specification No. ETI/OHE/13(4/84).Spring washers wherever

used shall be procured from RDSO’s approved manufactures .

5.1.8.4 All ferrous parts used in the manufacture of the isolator shall be hot-dip galvanized to RDSO’s specification No.ETI/OHE/13(4/84).

5.1.9 Earthling

5.1.9.1 The frame of the isolator shall be provided with two ear thing studs of size of size M 16, complete with flat washer, nut and locknut, for connection to the earth mat with the help of MS flat. The ear thing stud

shall be marked with “Earth” symbol.

5.1.9.2 Two number each of earthling terminals shall be provided for earthling the operating mechanism boxes of the Isolator and the earthling switch.

5.2 Operating mechanism

5.2.1 Isolator

5.2.1.1 The isolator shall be suitable for being conveniently operated manually from the ground level without any strain. The design shall permit the length of operating rod to be s adjusted that, with the isolator mounted in working

position, the rotating shaft of the operating mechanism on which the operating handle would be connected I at a height of 1.1 m from the

ground level. 5.2.1.2 Operating mechanism shall be provided with a sealed type reduction gear

unit so as to facilitate easy operation of the isolator. Means for greasing the gear assembly shall be available for periodical maintenance of the unit.

5.2.1.3 Suitable arrangement shall be made on the inner side of the operating

mechanism door for keeping the operating handle when not in use.



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5.2.1.4 A mechanical ON/OFF indicator shall be provided on the operating

mechanism box for indicating the isolator position. This should be visible from a distance.

5.2.1.5 The operating mechanism shall be designed in such a way so that, which minimum modifications, the isolator can be converted from manual to

motor- operated. 5.2.1 6. The operating mechanism and accessories shall be enclosed in a weather ,

dust and vermin-proof cabinet of sheet steel construction having a minimum thickness of 2mm.The operating mechanism box shall be hot-dip

galvanized to RDSO’s Specification No.ETI/OHE/13(4/84).

5.2.2 Earthling switch

5.2.2.1 Earthling switch shall be suitable for being conveniently operated manually

from ground level without any strain. The design shall permit the length of operating rod to be so adjusted that, with the ear thing switch mounted in working condition, the hinge pin of the operating handle is at a height of

1.1m from the ground level.

5.2.2.2 The operating handle shall rest in the vertical position, both when the ear thing switch is in Open/Close position.

5.2.2 3 A mechanical ON/OFF indicator for ear thing switch position, when the operation of the ear thing switch is complete, shall be provided on the ear

thing switch assembly. This indication should be visible from a distance.

5.2.2.4 A weather, dust and vermin-proof cabinet of sheet steel construction having a minimum thickness of 2 mm shall be provided for housing the interlock and integral lock. The cabinet shall be hot-dip galvanized to

RDSO Specification No.ETI/OHE/13 (4/84).



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5.3 Cylindrical post insulators (Support insulator)

5.3.1 The cylindrical post insulators shall conform entirely to RDSO Specification

No.ETI/OHE/64(10/88).Including the latest amendment .However, the

salient characteristics of the insulators are given below for ready reference:

S.

No.

Particulars Rated System Voltage

72.5kV 123kV 145kV 245kV

(1) (2) (3) (4) (5) (6)

i. Nominal System Voltage 66kV 100/110kV 132kV 220kV

ii. Overall height 770

+/-1mm

1200

1+/-1mm

1500

+/-2.5mm

2300

+/-3.5mm

iii. Maximum diameter of

Insulating part

195mm 210mm 270mm 300mm

iv. Top metal fitting pitch

circle diameter

127mm 127mm 127mm 127mm

v. Bottom metal fitting

pitch circle diameter

127mm 127mm 127mm 200mm

vi. Minimum creep age

distance

1810mm 3075mm 3625mm 6125mm

vii. Visible discharge test

voltage.

53kV 88kV 106kV 176kV

viii. Wet 1 minute power

frequency withstand

voltage

160kV

(rms)

230kV

(rms)

275kV

(rms)

460kV

(rms)

ix. Impulse voltage with

stand value

350kVp 550kVp 650kVp 1050kVp

x. Minimum failing load in

bending

4kN 4kN 4kN 4kN

xi. Minimum failing load in

tension

35kN 50kN 60kN 160kN

xii. Minimum failing load in

torsion

2kNm 3kNm 3kNm 3kNm

xiii. Minimum failing load in

compression.

70kN 100kN 120kN 160kN

5.3.2 The insulator shall be produced only from RDSO approved manufacturers.

5.4 Locking and inter locking

5.4.1 Isolator

5.4.1.1 The operating mechanism box shall have provision for a pad lock for



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Locking its door.

5.4.1 2 The isolator shall have provision for locking its main rotating shaft with the help of pad lock , both in ‘Open’ as well as in ‘Closed’ position shall not be possible.

5.4.1 3 Besides the above, the isolators shall have two locking mechanisms, for the

purpose of interlocking with the associated Circuit Breaker(s). The Inter Locking shall be as per Scheme –I and II detailed in Drg. No. ETI/PSI/5212 attached with this Specification. The locks for this purpose shall not be in

the scope of supply by the successful tenderer. However mounting arrangement for these locks shall be provided by the manufacturer in such

a way that it is possible to insert the key(s) from outside for operation of locks(s). The successful tenderer shall coordinate with manufacturer of circuit breaker and the purchaser for this purpose.

5.4.2 Ear thing switch:

5.4.2.1 The operating mechanism box shall have provision for a pad lock for locking

its lid.

5.4.2.2 A mechanical inter lock shall be provided in the operating mechanism of isolator and ear thing switch, so that operation of ear thing switch is

possible only when the isolator is locked in open position .This inter lock shall also prevent closing of isolator unless ear thing is locked in open position.

5.4.2.3 An integral lock shall be fitted in the operating mechanism box of the ear

thing switch for locking the operating mechanism both in ‘Open’ as well as in ‘Closed’ positions.

5.4.2.4 The design of the ear thing switch shall be such as to permit use of a pad

lock for locking the operating handle of the ear thing switch in both ‘Open’

as well as in ‘Closed’ positions.

5.4.3 The locking mechanism mentioned in Clause 5.4.2.3 shall be housed within the operating mechanism box. It shall however, be possible to insert the key from outside for operation of lock.

5.5 Bearings

5.5.1 The design and construction of various bearing shall embody all the features

required to with stand the climatic conditions specified to ensure reliable



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operation even after long periods of inaction .The bearings used shall be of maintenance free construction for entire life of isolator.

5.6 Support Structure

5.6.1 The support structure shall not form part of the tender and shall be arranged by the purchaser. Details of the drilling schedule of the holes for the purpose

of mounting the isolators on the support structure shall be ascertained by the successful tender from the purchaser before manufacturing the proto type.

5.6.2 The isolator and the ear thing switch (Wherever provided) shall be mounted rigidly in upright position on the support structure. The height of the support

structure from the ground level, for all types of isolators shall be 3000mm. 5.7 Tandem pipes

5.7.1 For smooth operation of the isolator, and to avoid buckling and bending of

the tandem pipes of the isolators, while opening or closing, an arrangement as indicated in sketch No. ETI/PSI/SK/322 enclosed with specification, shall be provided. An adjustable turn buckle /nut shall be provided (as shown in

the sketch), for adjusting the length of the tandem pipe (s) at site.

5.8 Nameplate 5.8.1 The isolator and the ear thing switch shall be provided with a separate

nameplate each, which shall be water –proof and corrosion-proof, and mounted such that it is clearly visible by a person standing on the ground.

Following information shall be indicated indelibly on these nameplates:

5.8.1 Isolator

Name of manufacturer

Type designation Serial Number

Rated voltage Basic Insulation Level Rated shot- time with stand current for one second.

Weight.

5.8.2 Ear thing switch

Name of manufacturer



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Type of designation Serial Number

Rated voltage Rated short- time withstand current for one second.

The terminal shall be complete with its steel mounting frame

6.0 LOCKING:

A bolt type integral lock and /or interlock, as specified by the

purchaser, of approved type shall be fitted on the isolator to enable the operating handle of the isolator to be locked effectively in the open as well as

in the close position. It shall not be possible to withdraw the key from the integral lock except when the isolator is locked either in the open or in the closed position.

The operating mechanism shall be so designed as to permit padlocking,

in addition to the integral lock and or interlock, for locking the operating handle of the isolator both in the open as well as in the closed positions.

In addition to locking arrangement described in clause 8.1, the design of operating mechanism shall permit its operation in a predetermined

sequence related to the operation of other switchgear with the help of suitable inter locks.

The internal mechanism of integral lock and inter lock shall be of stainless steel or non-ferrous material. It shall be of robust construction. The

outer housing of the interlock and integral lock shall be chrome plated steel and the construction shall be such that it is not prone to theft. The integral

lock and interlock shall be obtained only from the approved manufacturers. Electrical/mechanical interlocking shall be provided for manual/motorized operation.

Each lock shall be supplied with two keys. Key/lock number shall be inscribed on the keys /locks.

7.0 EARTH CONTACT ASSEMBLY:

The design of the isolator shall be such that it is possible to incorporate an additional pair of contacts so as to effectively earth the fixed contact of the

isolator in open position even at a later date. The design of the isolator frame shall permit the provision of the earth contact assembly without calling for modification to the frame itself. Two holes of 15.5 + 0.5 mm dia shall be



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provided on the mounting channel for connecting assembly shall be rated for the short time current specified in clause 4.0 (9) & (10).

8.0 ARCING HORN:

The single pole isolator shall be provided with arcing horns which shall be of

bright steel to Gr. 20-c-8 of IS: 1570 (Pt. II )- 1979. The arcing horns shall make contact before the main contacts close and break contact after the main

contacts break. 9.0 Motor:

Permanent Magnet DC motor ½ HP, 373 watts and above shall be suitable for

operation on 110V DC/24V DC Power from a battery. The voltage at the motor terminals likely to vary between 110% to 85% of the normal value.

9.1 GEAR:

The dis-connector/ isolator may be required to operate occasionally, with considerably long idle intervals. Special care shall be taken for selection of material for gear and lubrication of gears to meet this requirement. The gear

shall be made out of aluminum bronze or any other better material lubricated for life with graphite or better quality non-drawing and non-hardening type

grease .Whenever necessary automatic relieving mechanism shall be provided suitable relay, Device shall be provided to prevent over loading of the motor. Single phase preventer (for 3 phase meter) shall be provided to operate on

open circuiting of any phase and shall trip off the motor. Complete details of the devices shall be furnished in the offer.

9.2 Space heaters:

Space heaters suitable for 1 phase 240V Ac supply shall be provided for each motor operated operating mechanism to prevent condensation and shall be

operated by MCB.

9.3 Terminal blocks and wirings: Each operating mechanism shall be provided with 1100V grade stud type

terminal block. All auxiliary switches, interlocks and other terminals shall be wired up to terminal block. The terminal block shall have at least 20% extra

terminals. All wiring shall be carried out with 1.1 KV grade insulated 2.5 sq. mm copper wires.



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10.0 TESTS:

10.1 Type tests Only after all the designs and drawings have been approved and clearance

given by RDSO/Chief Electrical Engineer to this effect, the manufacturer shall take up the manufacture of the prototype. It is to be clearly understood that

any changes to be done in the prototype as required by RDSO/Chief Electrical Engineer shall be done expeditiously.

Before giving the call to RDSO/Chief Electrical Engineer for inspection and testing of the prototype, the manufacturer shall submit a detailed test

schedule prototype, the manufacturer shall submit a detailed test schedule consisting of schematic circuit diagram for each of the test and the nature of the test, venue and duration of each test and the total number of the days

required to complete the test at one stretch. Once the schedule is approved, the test shall invariably be done accordingly. However, during the process of

type testing or even later, RDSO/ Chief Electrical Engineer’s representative reserves the right to conduct any additional test(s) beside those specified herein, on any equipment/ sub- system or system so as to test the system to

his satisfaction or for gaining additional information and knowledge. In case any dispute or disagreement arises between the manufacturer and RDSO/ the

Chief Electrical Engineer during the process of testing as regards the type tests and / or the interpretation and acceptability of the type test results, it shall be brought to the notice of the Director General (Traction Installations),

RDSO/Chief Electrical Engineer as the case may be, whose decision shall be final and binding.

The following tests shall be carried out on the prototype unit of the

isolator and earthing switch at the works of the manufacturer/ sub- contractor or at a reputed testing laboratory, in the presence of RDSO/Chief Electrical Engineer’s representative(s) in accordance with the relevant governing

specification and/or as modified or amplified hereunder against each test:

i Visual examination of isolator and its parts. ii Dimensional verification of parts iii Assembly and interchangeability

iv Measurement of resistance of main circuit and /earth circuit (Before and After Mechanical Endurance test)

v Temperature rise test (before and after mechanical endurance test) vi Mechanical endurance test vii Short time rated current test.



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viii One minute wet power frequency test across the isolating distance and to Earth.

ix Impulse voltage withstand test across isolating distance and to earth x Galvanization test xi Chemical analysis of materials – copper contacts, springs, fasteners

and Bushes xii Physical tests on springs and fasteners and copper strips.

xiii Closing /Opening operations will be carried out with stored energy of the battery in fully charged condition to verify suitability of the battery provided by manufactures.

10.2 Acceptance tests

10.2.1 For the purpose of acceptance isolators shall be offered for inspection in lots

containing components for not more than 50 assemblies of same type of

isolators. The isolators offered for inspection shall first be routine tested by the manufacturer and defective components removed.

10.2.2 The visual examination and measurement of resistance shall be done on all

the isolators offered for inspection .The defective ones shall be either

attended to or removed before tests are conducted.

10.2.3 The following shall comprise the acceptance test: i) Visual examination (on every item of the lot)

ii) Dimensional verification of parts (on 10% sample of the lot, minimum

one Number) iii) Assembly and interchangeability (of minimum 3)

iv) Galvanization test (one sample of each item) v) Measurement of resistance (all samples)

vi) 10 closing /Opening operations will be carried out with stored energy of the battery in fully charged condition to verify suitability of the battery provided by manufactures.

10.2.4 The inspector may, at his discretion, conduct any or all of the tests (clause

10.1), (clause 10.2) and (clause 10.3) for a particular lot. The manufacturer shall arrange for the test.

10.2.5 Acceptance Criteria

10.2.5.1 If during dimensional verification of parts assembly and interchangeability, any component fails to meet the requirement of this specification, twice the number of the same shall be taken and the tests repeated. If the



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component(s) fail to meet the requirement again, the lot shall be rejected. The manufacturer may sort out the defective pieces and offer

the lot once again, should there be any failure in the lot offered once again, the lot shall be rejected totally.

10.2.5.2 If the sample fails to meet the requirements of Cl 9.0 twice the number of samples for same components/ assembly shall be drawn and subjected

to the same test. Should the sample fail in the re- test, the lot of particular component will be rejected. The manufacturer may reassemble the isolators using the new components and offer once again for

inspection.

10.3 Routine tests. The manufacturer shall carry out the following as routine tests:

a. Visual examination.

b. Dimensional verification of parts. c. Assembly and interchangeability. d. Power frequency voltage dry withstand tests (on the Isolator

only) for72.5kV & above. e. Measurement of contact resistance for 72.5kV & above.

The manufacturer shall offer record of the routine tests and acceptance tests

carried out by him to ensure quality of raw materials, to the inspector. Unless

these are satisfactory, no acceptance test shall be carried out, Mention of routine tests and acceptance tests carried out by the manufacturer shall be

made in the test report and salient extracts reproduced.

11.0 TEST METHODS 11.1 Visual examination

All components shall be visually examined to check that they are properly

manufactured, do not have sharp edges and corners, the tubes are not crooked or bent and galvanization of ferrous components is free from visible defects mentioned in Appendix ‘A’ of RDSO specification No. ETI/OHE/13

latest version. The finish of stainless steel fasteners and pins shall be smooth and bright.



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11.2 Dimension verification

The components of the isolators, particularly –moving contact blade, the spring of the fixed contact, the housing for fixing contact jaws on the post insulators, the fixed and moving contact jaws, the operating shaft for the

operating pipe and the contacts shall be checked with respect to the approved drawings. The components shall be in accordance with the approved

drawings. 11.3 Assembly and interchangeability

11.3.1 The isolator shall be assembled, using the components picked up at random

from different lots .No adjustments shall be required in any assembly the isolator shall function smoothly without any adjustments.

11.3.2 The components such as the housing for the fixed and moving contacts, the housing for the earth contact assembly shall then be interchanged to ensure

to ensure that the components are fully interchangeable. Fixing of different components shall be without any difficulty and any special adjustment.

11.3.3 The dimensions of the isolator assembly, particularly the following critical ones shall be verified.

i. Minimum clearance between moving blade and the jaw of the fixed

Contact at free end when the isolator is open.

ii. The clearance between the earth end of the operating rod insulator with Both the live terminals in closed as well as open positions.

iii. The travel of the moving blade with full travel of operating pipe. iv. The distance between the centers of all the holes of the isolator

Assembly for fixing it on the masts. v. When the isolator is in fully closed position, the moving contact shall

go home fully into the fixed contact and no portion shall Remain

Projecting beyond the fixed contact on the upper side. The main contact shall not exert undue pressure on the stopper.

11.4 Measurement of the resistance of the main circuit/earth circuit.

11.4.1 This measurement is made for comparison between the isolator type tested for temperature rise and all other isolator of the same type subjected to

acceptance tests.



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11.4.2 The direct current of any convenient value between 100 A and the rated normal current shall be passed through the main circuit /earthing contact

circuit as the case may be and the voltage drop between the two terminals of each pole of the isolator shall be measured to obtain the resistance at the ambient temperature. All values measured/obtained shall be recorded.

11.4.3 The measurement of resistance shall be made before the temperature rise

test. 11.4.4 The test shall also be conducted during acceptance test. The maximum

value of resistance shall not exceed 1.5 times the resistance obtained during type tests or RxT/t,

Whichever is lower, where – R = Resistance obtained during type test.

T = Permissible temperature rise (35 deg. C) t = Temperature rise obtained during type tests at the hottest spot.

11.4.5 For the purpose of the acceptance test, the measurement of resistance may

be made by using micro-ohm meter calibrated to the satisfaction of the

inspector.

11.5 Temperature rise test 11.5.1 The test for temperature rise of main circuit shall be made on a new isolator

with clean contact pieces. The isolator shall be mounted approximately as under usual service conditions, including all normal covers of any part of the

isolator, and shall be protected against undue heating or cooling.

11.5.2 Temporary connections to the main circuit shall be such that no appreciable amount of heat is conducted away from or conveyed to the isolator during the test. In case of doubt, the temperature rise of the terminals of the main

circuit and at temporary connections at a distance of 1 m from the terminals shall be measured. The difference of temperature shall not exceed 50 C.

11.5.3 The test shall be made with the rated normal current of the isolator (i.e.

1250A for isolators for SSP and SP, 1600 A for isolators to be used at FP and

TSS and 3150 A for type III isolators) and at rated frequency (50Hz +/-3%).

11.5.4 The duration of the test shall be made over a period of time sufficient for the temperature to reach a steady state i.e. when the variation of temperature does not exceed 1 deg. C per hour over three hours.



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11.5.5 The temperature of the different parts shall be measured with

thermometers, thermocouples or other suitable means, placed at the hottest accessible spot. The following precautions shall be taken when measuring with thermocouples or thermometers:

i. Thermocouples or the bulbs of thermometers shall be protected

against being cooled from outside during the test. The protected surface area shall, however, be negligible when compared with the cooling surface area of the part under test.

ii. Good heat conductivity between the bulb of the thermometers or the

thermocouples and the surface of the part under test shall be insured.

iii. Alcohol thermometers shall be used as they are accurate for such purposes.

11.5.6 The time for the whole test may be shortened by preheating the circuit with

a higher value of current.

11.5.7 In case the temperature rise at any part of the isolator exceeds the values

specified in Clause 4.0(11), the isolator shall deemed to have failed in the test.

11.6 Mechanical Endurance Test

11.6.1 The mechanical endurance test shall be conducted in accordance with IS: 9921 (Pt. IV) but the number of operating cycles shall be 5000 instead of

1000 as specified their n. The condition of all parts shall be satisfactory after the test. On successful completion, the test shall be continued up to 10000 cycles to determine the weak spots.

11.6.2 For this test, the isolator shall be complete with operating and locking

mechanism etc. 11.7 Short time withstand current test

11.7.1 The test shall be conducted at the current value specified in Clause 4.0 (9)

for 3 s.The ac component of the test current shall be equal to the ac component of the rated short time withstand current of the isolator or



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Earthing switch. The peak current shall not be less than the rated peak withstand current but shall not exceed it by more than 5% without the

consent of the manufacturer. 11.7.2 The value of the test current and its duration shall be such that I1

2 .t1=I2.t

Where – I1= r.m.s. component of test current measured in accordance with Appendix

to IS: 9921(Pt.IV) in A. I = r.m.s. component of specified short –time current in A (20,000 A). t = Specified short time current duration in seconds (3 s)

t1 = Duration of current in s. Note: This test shall be conducted at Central Power Research Institute,

Bangalore/Bhopal only, unless otherwise approved by RDSO. 11.7.3 During the test to prove its capability of carrying the rated peak withstand

current and the rated short time withstand current, the isolator or earthing switch shall not show undue stress. After the test, the isolator or earthing

switch shall not show any material deterioration and shall be capable of operating normally.

11.7.4 Visual inspection and no-load operation of the tested isolator or ear thing switch are usually sufficient to check these requirements.

11.7.5 The test may be considered completed successfully if the isolator can be

operated manually after tests. There should be no damage, which may

affect its mechanical and electrical performance.

11.7.6 If after the test, there is any doubt about its current carrying capability; temperature rise test shall be made before the isolator is reconditioned. The

value of temperature rise shall not exceed the figure given in Clause 4.0(9). 11.8 Wet power frequency voltage withstand test

11.8.1 The isolator and earthing switch shall be subjected to wet power frequency

voltage withstand test in accordance with IS: 2071 (Pt. I & II).The test voltage shall be raised for each test condition to the rated withstand voltage, duly corrected for the ambient atmospheric conditions, specified in

Cl. 4.0(11) and shall be maintained for 1 min. No disruptive discharge shall take place during the 1 min period.

11.8.2 The wet power frequency voltage withstand test shall be conducted in

accordance with IS: 2071 (Pt. I). However, if the water of prescribed



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resistivity cannot be obtained, water of lower resistivity may be used, provided that the isolator passes the test. The actual value of resistivity of

the water and the rate of precipitation (both horizontal and vertical components) shall be stated in the test report.

11.8.3 The test shall be conducted in following conditions:

11.8.3.1 Between isolator and earth: With the isolator in the closed position, the test voltage shall be applied to one of the 25kV terminals, the support frame – work and the other pole connected together and earthed.

11.8.3.2 Across isolating distance: With the isolator in the open condition, the test

voltage duly corrected for ambient conditions, shall be applied at the moving blade(s)and the other two terminals shall be connected to the earth of the testing transformer. The whole isolator shall be adequately

insulated from the ground to prevent possibility of direct flashover. Note: If the order is for both single pole and double pole isolators, these

tests would be conducted on a double pole isolator with earthing wheel.

11.9 Lightning impulse voltage tests

11.9.1 If the order is for both single pole and double pole isolators, this test shall be conducted on a double pole isolator with earth contact assembly. Isolator and earthing switch shall be subjected to dry lightning impulse voltage test,

with both positive and negative polarities using standard 1.2/50 micro-second lightning impulse according to IS: 2071(Pt. I).

11.9.2 Impulse voltage test between isolator and earth

With the isolator in closed opposition and earthing switch open, 15

consecutive impulses of 250kV duly corrected for the ambient atmospheric

conditions, shall be applied between one terminal and the frame, the other pole being connected to the frame. The isolator shall be considered to have

passed the test, if number of disruptive discharges to frame or to the adjacent pole does not exceed two.

11.9.3 Impulse voltage test across isolating distance

The isolator shall be in the open position. The frame – work shall be adequately insulated from earth so as to prevent any disruptive discharges



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direct to earth. Lightning impulses of 290kV duly corrected for ambient conditions shall be applied to the moving blade(s). The remaining two

terminals shall be connected to the earth .The isolator shall be deemed to have passed the test if there is no disruptive discharge to the opposite terminals.

11.10 Galvanization test

11.10.1 In the type test, at least two samples of each type of component which has

been galvanized shall be tested for ensuring that the galvanizing done

conforms to specification no. ETI/OHE/13 in regard to adherence, uniformity and mass of zinc coating .The mass of zinc coating shall be not

less than 610 g/m2. 11.10.2 In the acceptance test, one sample of each type of component which has

been galvanized shall be tested for ensuring that the galvanizing done conforms to specification no. ETI/OHE/13 in regard to adherence,

uniformity and mass of zinc coating .The mass of zinc coating shall be not less than 610 g/m2.

11.11 Chemical analysis of materials

11.11.1 The chemical analysis of phosphor bronze springs, copper tube/strips of moving and fixed contacts and stainless steel fasteners shall be conducted in accordance with IS: 7608,IS: 191 and RDSO specification No.

ETI/OHE/18 as applicable. The material shall conform to the requirements specified.

11.11.2 Physical tests on fasteners shall be conducted in accordance with RDSO

specification No. ETI/OHE/18. The results shall be in accordance with the requirement laid down in the specification.

11.11.3 Physical tests on the springs and on copper strips/Tubes shall be conducted in accordance with IS: 7906(Part II)-1985 and IS: 1897-1983 respectively.

12.0 Bulk Manufacturing

12.1 Only after clear written approval of the results of the tests on the prototype is communicated by RDSO/Chief Electrical Engineer to the manufacturer,

shall he take up bulk manufacture of the equipment –which shall be strictly with the same material and process of manufacture as adopted for the prototype .In no circumstances shall material other than those approved in



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the designs /drawings and/or the prototype be used for bulk manufacture on the plea that they had been obtained prior to the approval of the

prototype.

12.2 If the prototype of an isolator or earthing switch conforming to this

specification has been approved for earlier supplies to Indian Railways, testing of prototype again may be waived provided that no changes in the

design or material(s) used or the process of manufacture have made. 13.0 Technical data and drawing

13.1 The tenderer shall furnish along with his offer the guaranteed performance

data and other technical particulars of the equipment in the proforma attached at Appendix ‘A’.

13.2 The information furnished in the Schedule of Guaranteed technical, performance, data and other particulars shall be complete in all respects. If

there is any entry like “shall be furnished later” or blanks are left against any item of Schedule of guaranteed particulars, the tender is not likely to be considered as such omissions cause delay in finalizing the tender.

13.3 Reports of the type tests, if conducted on the similar equipment shall also

be furnished. 13.4 The tenderer shall specifically indicate in a statement attached with his

offer, his compliance with each clause and sub-clause of this specification. If any vague remark on any clause or sub –clause of this specification is

given by the tenderer, then the tender submitted by him is not likely to be considered. A separate deviation statement shall be furnished with the offer

drawing attention to the clause(s) where the tenderer seeks deviation giving detailed remarks/justification thereof. If there are no deviations, a ‘NIL’ statement shall be furnished.

13.5 The tenderer shall furnish along with tender the following drawings:

i. General arrangement drawings showing the outline

dimensions of isolators and earthing switch (whenever

provided) ii. Drawings for support insulators along with salient technical

particulars. iii. Drawings for operating mechanism of main isolator. iv. Drawing for operating mechanism of earthing switch.



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v. Any additional drawing if required

13.6 The manufacturer shall be required to submit the following detailed dimensioned drawings including drawings already mentioned in clause 13.5 above, as per Railways standards in size of 210 mm X 297 mm or in integral

multiple thereof, for approval: i Details of main contacts.

ii Details of earthing contacts iii Interlocking arrangement iv Castle type integral lock

v Mounting details of isolator vi Terminal connector

vii Motor and charger details along with circuit diagram viii Loads exerted by the isolator & earthing switch (wherever provided)

for designing the mounting structure. This drawing should furnish

Complete information regarding loads and their point of application.

13.7 After approval, six copies of approved drawings along with two sets of reproducible prints shall be supplied to each consignee. Two copies of drawings along with one set of reproducible prints shall be supplied to the

Director General (TI), Research Designs and Standards Organization, Manak Nagar, Lucknow – 226 011.

14.0 Installation, Testing and Commissioning

Twenty sets of installation, operation and maintenance instructions shall be supplied to the Purchaser with every order. Two copies of these instructions

shall be supplied to the Director General (TI), RDSO, Lucknow. The information shall necessarily include

i Procedure for erection and precautions to be taken during the process. The

details of maintenance practices to be adopted under normal service

conditions. The number of operations (or the period) after which different parts of isolators and/or earthing switch requires to be specifically attended

to shall be indicated. ii Procedure for overhauling of isolator and/or earthing switch. iii Procedure for replacement of parts, like contacts, subject to wear and tear

and deterioration during service. iv List of special tools required for maintenance /replacement.

v List of special parts required for 5 years maintenance. vi Lubrication instructions including type of lubricants and quality to be used.



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15.0 Clause wise conformity, deviations etc.

The tenderer shall specifically indicate in a statement attached with his offer, his compliance with each clause and sub-clause of this specification. A

separate statement shall be attached with the offer indicating references to the clauses where the tenderer deviate there from together with detailed

remarks/justification. If there are no deviations, a ‘NIL’ statement shall be attached. Any deviation from this specification which the tenderer proposes to improve upon the performance, utility and efficiency of the equipment will

be given due consideration, provided full particulars of the deviation with justification thereof are furnished, and are found acceptable by RDSO. In

case of any contradiction between the provisions of the Indian Standards Specification/IEC standard and this specification, the latter shall prevail.

16.0 Warranty

16.1 The successful tenderer/ manufacturer shall warrant that all equipment shall be free from defects and faults in design, material, workmanship and manufacture and of the highest grade consistent with the established and

generally accepted standards for the equipment of the type ordered and in full conformity with the specifications and shall operate properly.

16.2 This warranty shall cover inspection of, payment for and acceptance of the

equipment, but shall expire 30 (Thirty) months after the delivery at ultimate

destination, or 24(Twenty four) months from the date of commissioning and proving test of the equipment at ultimate destination in India, whichever

period expires earlier, except in respect of complaints, defects and/or claims notified to the successful tenderer/manufacturer within 3(Three) months of

the expiry of such date. Any approval or acceptance by the Purchaser of the equipment shall not in any way limit the successful tenderer/manufacturer’s liability.

16.3 The successful tenderer/manufacturer’s liability in respect of any complaint,

defects and/or claims shall not be limited to the furnishing and installation of replacement of parts free of any charge or the repair of defective parts only to the extent that such replacement or repairs are attributable to or arise

from faulty workmanship or material or design in the manufacture of the goods, provided that the defects are brought to the notice of the successful

tenderer/manufacturer within 3(Three) months of their being first discovered during the warranty period of 3(Three) months from the date of expiry of



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warranty period, or at the option of the Purchaser, to the payment of the value, expenditure and damage as hereafter mentioned.

16.4 The successful tenderer/ manufacturer shall, if required, replace or repair the

equipment of such portion thereof as is rejected by the Purchaser free of cost

at the ultimate destination or at the option of the Purchaser. Successful tenderer/manufacturer shall pay to the Purchaser value thereof at the

contract price or in the absence of such price at a price decided by the Purchaser and such other expenditure and damages as may arise by reason of the breach of the conditions herein specified.

16.5 All replacement and repairs that the Purchaser shall call upon the successful

tenderer/manufacturer to deliver or perform under this warranty shall be delivered and performed by the successful tenderer/manufacturer, promptly and satisfactorily and in any case within 2(Two) months of the date of advice

to this effect.

16.6 If the successful tenderer /manufacturer so desires, the parts that are removed may be taken over by him or his representative for disposal as he deems fit at the time of replacement with good parts. No claim whatsoever

shall lie on the Purchaser thereafter for the parts so removed.

16.7 The warranty herein contained shall not apply to any material which shall have been repaired or altered by the Purchaser or on his behalf in any way without the consent of the successful tenderer/manufacturer, so as to affect

the strength, performance or reliability or to any defects to any part due to misuse, negligence or accident.

16.8 The decision of the Purchaser in regard to successful tenderer/manufacturer’s

liability and the amount, if any, payable under this warranty shall be final and conclusive.

17.0 Training of Indian Railway’s engineers

The offer shall include the training of two engineers of the Indian Railways free of cost at the manufacturer’s works in India or abroad and at the maintenance depots/workshops on a Railway system or other public utility

where circuit breakers of similar/identical design are in operation. The total duration of training for each engineer shall be 4 weeks of which

approximately two weeks will be at manufacturer’s works and two weeks on a Railway system or other public utility. If the country of manufacturer is not India, the cost of travel to that country and back will be borne by the Indian



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Railways. Other details shall be settled at the time of finalizing the contract/Purchase Order.

18.0 Packing and Dispatch

18.1 Various components of the isolator and /or earthing switch shall be securely packed in a proper manner in a wooden crate/box. It shall be ensured that

one crate/box does not contain components of more than one complete isolator and/or earthing switch A detailed packing list with weight and overall dimensions of the crate/box shall be furnished for each crate/box indicating

the following:

Crate/Box No.

Description of each component in the crate /box

Gross weight in kg

Outside dimensions

of crate /box

18.2 The weight of a crate /box containing all components shall be such that it can be manually handled conveniently by more than two persons.

18.3 Necessary instructions for handling and storage shall also be furnished for use at the receiving end.

--------------



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Annexure–A

to Specification No. TI/SPC/PSI/ISOLTR/0130

SCHEDULE OF GUARANTED PERFORMNCE DATA TECHNICAL AND OTHER

PARTICULARS FOR ISOLATOR.

Sl.

No. Description Unit of

measurement.

Values to be

supplied by

tenderer

1. Name of manufacturer.

2. Country of origin.

3. Standard specification on which

performance is based.

4. Manufacturer’s type designation.

5. Rated voltage. kV

6. Rated current A

7. a) Isolator

b) Earthing switch A

8. Rated frequency Hz.

9. Rated insulation level

a) Rated one minute power frequency wet withstand voltage.

i. To earth and between

poles

ii. Across isolating distance.

kV(rms)

kV(rms)



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b) Rated one minute power frequency dry withstand

voltage. i. To earth and between

poles

ii. Across isolating distance.

kV(rms)

kV(rms)

c) Standard lightening impulse

(1.2/50 micro second) withstand voltage -

i. To earth and between

poles

kVp

ii. Across isolating distance. kVp

10.

Rated short time withstand

current (for 1 second)

i. Isolator

ii.Earthing switch

kA(rms)

kA(rms)

Dynamic peak withstand current

:

i. Isolator

ii.Earthing switch

kAp

kAp

11. Maximum temperature rise over

an ambient temperature of 40

deg.C

When carrying its rated current.

Deg.C.

i) Copper contacts



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ii) Terminal pad of the isolator

to be connected to

terminal connectors by

both.

iii) Metal parts acting as spring.

12. Breaking capacity of capacitive

current at rated voltage.

A

13. Number of poles. Number

14. Number of breaks per pole Number

15. Total length of break per pole mm

16. Centre distance between poles mm

17. Minimum clearance in air

a. Between poles mm

b. Between the live part and

earth

mm

c. Between open contacts of the

same pole.

mm

d. Isolating distance. mm

18. Contact

a) Material of the moving contact.

b) Material of the fixed contact.

c) Thickness of silver coating. Micron.

d) Contact pressure. Kg.



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19. Operating mechanism.

a. Type

b. Height of the rotating shaft

on which operating handle shall

be connected.

m

c. Thickness of the sheet metal

for operating mechanism box.

m

d. Gear ratio

e. Number of turns the handle

is to be rotated to fully close

the isolator from its fully open

position.

Number.

f. Weight of the operating

Mechanism.

Kg.

20. Insulator

a. Name of manufacturer.

b. Type designation.

c. Standard specification on

which performance is based.

IS.

d. Number of stack

e. Weight of one insulator. Kg.



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f. Number of insulators used

i. Support

ii. Rotating/operating

g. Wet power frequency

Withstand voltage (1 minute).

KV (rms).

h. Dry power frequency

withstands voltage (1 minute).

KV (rms).

i. Visible discharge test

voltage

kV

j. Impulse withstand voltage kVp

k. Wet power frequency

flashover voltage.

kV(rms).

l. Dry power frequency

flashover voltage.

kV(rms).

m. Puncture voltage kV(rms)

n. Minimum failing load in

bending.

kN

o. Minimum failing load in

tension.

kN

p. Minimum failing load in

torsion.

kN



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q. Minimum failing load in

compression.

kN

r. Creepage distance in air mm

s. Shed profile

21. Type of bearings used in the

isolator.

22. Type and material of terminals.

23. Total weight

i). Isolator Kg.

ii). Earthing switch. Kg.

24. Number of closing and opening

operations, the isolator can perform

Without deterioration of its contacts.

Additional Information :-

25. Is contact silver plated? Yes/no

26. Is pad locking arrangement for

operating mechanism box provided?

Yes/no

27. Is mounting arrangement for

interlock(s) on isolator operating

mechanism provided?

Yes/no

28. Is integral lock on earth mechanism

provided?

Yes/no

29. Is mounting arrangement for

interlock with associated isolator

provided?

Yes/no



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30. Is mechanical interlocking

arrangement between earthing

switch and the isolator provided?

Yes/no

31. Is material of fasteners of 12mm dia

and below stainless steel?

Yes/no

32. Is material of fasteners above

12mm dia galvanized iron?

Yes/no

33. Is framework for the isolator is

made out of steel galvanized?

Yes/no

34. Two number each of earthing studs provided for –

a. Isolator frame Yes/no

b. Earthing switch frame Yes/no

c. Operating mechanism box. Yes/no

d. Earthing symbols provided. Yes/no

35. Is height of operating handle hinge

pin in earthing switch from ground

level 1.1m?

Yes/no

36. Is arrangement for keeping the

operating handle for isolator in the

operating mechanism box provided?

Yes/no

37. Is the operating mechanism box for

the isolator is weather, dust and

vermin proof?

Yes/no

38. Is Open/Close indicator provided

for–



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a. Isolator Yes/no

b. Earthing switch Yes/no

39. Is padlocking provided for–

a. Main rotating shaft of isolator Yes/no

b. Operating handle for earthing

switch.

Yes/no

c. Lid cover for operating

mechanism box.

Yes/no

40. Are the bearings maintenance

free

Yes/no



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Annexure-B

The following information shall be furnished by the manufacturer /supplier:

Sl.No Description Values to be supplied

by tenderer

1.

24V, 40AH Lead acid battery& battery

charger

i)Description and type

ii)Type designation

iii)Make

iv)Identification mark

v)Governing specification

vi)Rating:

(a)Voltage



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2. Motor


ii)Type designation

iii)Make



vi)Rating:

(a)Voltage

(b) Wattage

(c)Power frequency voltage with stand

(d)Class of insulation

(e)continuous current

(f) Mode of protection

3 Motor limit switch


ii)Make

iii)Type designation

iv)Rating

(a)Voltage

(b) Continuous current



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4 MCB’s


ii)Type designation

iii)Make



6)Rating:

(e)Voltage

(f)continuous current

(g)Breaking and making current

(h)Electrical & Mechanical life(No.of

operations)

5 Heater


ii)Type designation

iii)Make


v)Rating: (a) Voltage

(b) Power

vi)Make and type designation of

thermostat(if used)



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6 Interlock:


ii)Type designation

iii)Make



vi) Electrical rating of switch use.

7 Power contactor


ii)Type designation

iii)Make



vi)Electrical rating of switch use

=============



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Annexure-C

DEFINITIONS

1. Isolator

It is a mechanical switching device which provides, in the open position, an isolating distance between the two contacts in accordance with specified requirements. An isolator is capable of opening and closing a circuit when either negligible current is

broken or made, or when no significant change in the voltage across the terminals at each pole of the disconnector (isolator) occurs. It is also capable of carrying

currents under normal circuit conditions and carrying, for a specified time, currents under abnormal conditions such as those of short circuit.

2. Earthing switch A mechanical switching device for earthing part of a circuit, capable of withstanding

for a specified time currents under abnormal conditions such as those due to short circuit, but is not required to carry current under normal conditions of the circuit.

3. Main circuit All the conducting parts of an isolator or earthing switch included in the circuit

which is designed to close or open. 4. Pole

The portion of an isolator or earthing switch associated exclusively with one electrically – separated conducting path of its main circuit and excluding those

portions which provide means of mounting and operating all poles together. 5. Closed position

The position in which the predetermined continuity of the main circuit is secured.

6. Open position The position in which the predetermined clearances between open contacts in the main circuit is secured.

7. Position Indicating Device

A device, which indicates, at the location of the isolator or ear thing switch, whether the contacts of the main circuit are in open or closed position.



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8. Interlocking Device A device, which makes the operation of the isolator or ear thing switch dependent

upon the position or operation of one or more other pieces of equipment. 9. Ambient Temperature

The temperature determined under prescribed conditions, of the air surrounding the complete switching device (e.g. for enclosed switching device, it is the air outside

the enclosure). 10. Operation Cycle

A succession of operation from one position to another and back to the first position through all other operations, if any.

11. Dependent Manual Operation An operation solely by means of directly applied manual energy, such that the

speed and force of the operation are dependent upon the action of the operator.

12. Rated value A stated value of any one of the characteristic value that serve to define the

working conditions for which the isolator or ear thing switch is designed and built.

13. Normal current The current which the main circuit of the isolator is capable of carrying continuously under specified conditions of the use and behavior.

14. Short-time withstand current

The current that an isolator or the ear thing switch can carry in the closed position during a short specified time period under prescribed conditions of the use and

behavior. 15. Permissible duration of short –circuit current

The time during which an isolator or ear thing switch in the closed position can carry a short – circuit current of specified value.

16. Permissible peak withstand current The value of peak current that an isolator or ear thing switch can withstand in the

closed position under prescribed conditions of use and behavior.



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17. Rated 1 min power frequency withstand voltage The r.m.s. value of sinusoidal alternating voltage at power frequency which the

insulation of the isolator or ear thing switch withstands under specified test conditions.

18. Rated impulse withstand voltage

The peak value of the standard (1.2/50 s) impulse voltage wave which the insulation of the isolator or ear thing switch can withstand under specified test conditions.

19. Clearance

The distance between the conducting parts along a string stretched the shortest way between these conducting parts.

20. Clearance between poles The clearance between any conducting parts of the adjacent poles.

21. Clearance to earth

The clearance between any conducting parts and any parts which are earthed or intended to be earthed.

22. Clearance between open contacts (gap) The total clearance between the contacts or any conducting parts thereto, of a pole

of an isolator or ear thing switch in the open position.

Isolating distance The clearance between open contacts or any conducting parts connected thereto in

a pole of an isolator meeting safety requirements.

===================

specification no. ti/spc/psi/isoltr/0130 ministry of...

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