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SPECIAL INSTRUCTIONS TO BIDDER
Please read following instructions carefully before submitting your bid.
1. All the drawings, i.e. elevation, side view, plan, cross sectional view etc., in AutoCAD
format and manuals in PDF format, for offered item shall be submitted. Also the hard
copies as per specification shall be submitted.
2. The bidder shall submit Quality Assurance Plan with the technical bid.
3. The bidder shall have to submit all the required type test reports for the offered item. In
absence of this, the evaluation shall be carried out accordingly as non-submission of type
4. The bidder must fill up all the points of GTP for offered item/s. Instead of indicating “refer
drawing, or as per IS/IEC”, the exact value/s must be filled in.
5. All the points other than GTP, which are asked to confirm in technical specifications must
be submitted separately with the bid.
6. The bidder is required to impart training in view of manufacture, assembly, erection,
operation and maintenance for offered item, at his works, to the person/s identified by
GETCO, in the event of an order, free of cost. The cost of logistics will be bear by
7. Please note that the evaluation will be carried out on the strength of content of bid only.
No further correspondence will be made.
8. The bidder shall bring out all the technical deviation/s only at the specified annexure.
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QUALIFYING REQUIREMENT DATA
Bidder to satisfy all the following requirements.
1) The bidder shall be Original Equipment Manufacturer
(OEM). The offered equipment have to be designed,
manufactured and tested as per relevant IS/IEC with
2) The minimum requirement of manufacturing capacity of
offered type, size and rating of equipment shall be FIVE
times tender/ bid quantity. The bidder should indicate
manufacturing capacity by submitting latest updated
certificate of a Chartered Engineer (CE).
3) Equipment proposed shall be of similar or higher rating
and in service for a minimum period of THREE (3) years
and satisfactory performance certificate in respect of this
is to be available and submitted.
4) The bidder should clearly indicate the quantity and Single
Value Contract executed during last FIVE (5) years, for
the offered equipment. Bidder should have executed one
single contract during last five years for the quantity
equivalent to tender / bid.
The details are to be submitted in following format,
CE No. &
ITEMS QUANTITY ORDER
e) Equipment offered shall have Type Test Certificates from
accredited laboratory (accredited based on ISO/IEC
Guide 25 / 17025 or EN 45001 by the National accredition
body of the country where laboratory is located), as per
IEC / IS / technical specification. The type test reports
shall not be older than FIVE years and shall be valid up to
expiry of validity of offer.
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TECHNICAL SPECIFICATION FOR
66 kV SF6 GAS CIRCUIT BREAKER
SECTION – I
GENERAL TECHNICAL REQUIREMENTS
1.1 SCOPE :
1.1.1 This section covers the design, manufacture, testing, inspection,
supply and delivery of 66 kV SF6 gas Circuit Breakers SPRING
operated, along with associated accessories and complete in all
respects specified in the schedule of requirements.
1.2 APPLICABLE STANDARDS:
1.2.1 The equipment to be supplied under this specification shall conform to
the latest issue of standards, rules and codes some of which are
1. IEC-62271/ IS 13118 Specification for alternating current Circuit
2. IEC-60376 Specification and acceptance of new Supply of
3. IS: 2147 Degree of protection provided for Enclosures
for low voltage switchgear and control gear.
4. IS: 375 Marking and arrangement for switchgear bus-
bar, main connections and auxiliary wiring.
5. IS: 325 Specification for 3ph induction motor.
6. IS: 2516 Specification for circuit breaker.
7. IS: 2099 High voltage porcelain bushing.
9. IS: 2629 Recommended practice for hot dip galvanizing
of iron and steel.
The components & accessories to be used in the manufacture of circuit
breaker shall conform to relevant Indian Standards/the standard
specified under respective clause in this specification.
However, in the event the offered breakers confirming to any other
standard, salient points of differences between the standard
adopted and the specified standards shall be clearly indicated in the
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1.3.1 The bidder shall furnish the drawings in triplicate incorporating the
a) Drawing showing the general outlines dimensions of circuit
breakers, with clear identification of parts / items.
b) Drawing showing control cabinets and circuit diagrams for operating
mechanism of circuit breakers.
c) Drawing showing the complete operation cycle of the circuit breaker
d) Compression type terminal connectors for the breakers.
e) All the documents required shall be submitted over and above as
indicated in Section - V of the specification.
22.214.171.124 The Bidder shall submit the following drawings within 15 days from
the date of receipt of clear order: -
a) Outline dimensional drawings showing all parts / items, transport
weight etc. of circuit breaker & its support structure.
b) Detailed drawings of operating mechanism of circuit breakers.
c) Wiring and control diagram.
d) Drawings of foundation details, mounting structures, spacing of
e) Compression type terminal connectors, with STC rating, bill of
materials, etc., complete with all dimensions.
f) MQP, FQP, erection, operation & maintenance manuals.
126.96.36.199 The bidder may also, submit any other drawings found necessary in
addition to the drawings stated above.
1.4.1 GENERAL DESIGN FEATURES OF CIRCUIT BREAKERS:
188.8.131.52 The circuit breakers shall be capable of rapid and smooth
interruption of currents under all conditions completely suppressing
all undesirable phenomena even under the most severe and
persistent short circuit conditions or when interrupting small
currents or leading or lagging reactive currents. The circuit breakers
shall be ‘Restrike-Free’ under all operating conditions. The details
of any device incorporated to limit or control the rate of rise of
restriking voltage across, the circuit breaker contacts shall be
stated. The over voltages caused by circuit breaker while switching
inductive or capacitive loads shall not exceed 2.5 times the highest
phase to neutral voltage. The actual make and break times for the
circuit breakers throughout the ranges of their operating duties shall
be stated in the offer and guaranteed.
184.108.40.206 The arc quenching chambers shall have devices to ensure almost
uniform distribution of voltage across the interrupters.
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220.127.116.11 Breaking Capacity:
The interrupting capacity of the breaker for kilometric faults (short
line faults) shall be equal to its interrupting capacity as per IS:
13118 / IEC 62271 and shall be stated in the tender. The details of
tests conducted for confirming the capability of the breakers under
kilometric fault conditions shall be furnished in the offer.
18.104.22.168 The circuit breakers shall be designed for interrupting line charging
currents without undue rise in the voltage on supply side and
without any restrike and without showing signs of undue strain. The
guaranteed over voltage which shall not be exceeded while
interrupting the line charging currents as specified under the Clause
2.4.10 of Section-II of this specification shall be stated in the offer.
22.214.171.124 The circuit breakers shall be capable of interrupting small inductive
currents (occurring while switching off unloaded transformer)
without giving rise to undue over voltage and without restrikes. The
maximum over voltage value which will not be exceeded under
such conditions shall be stated in the offer, and in conformity to this,
test reports along with oscillograph shall be furnished in the offer.
126.96.36.199 Restriking Voltage:
The circuit breakers shall be capable of interrupting the rated power
when the restriking voltage has a frequency of not less than 400 Hz
and with a restriking voltage having frequency of 2000 Hz. The
circuit breakers shall be capable of interrupting at least 50% of
nominal breaking capacity.
188.8.131.52 The measures adopted for ensuring proper operation at high rate of
rise of restriking voltage and for limiting the actual voltage values
across the breaks shall be described in the tender. The type
characteristics and rating of the resistor used, if any, to shunt the
breaker contacts and of the auxiliary switching devices used for
interrupting the resistor current shall be clearly stated.
184.108.40.206 Recovery voltage and power Factor:
The circuit breaker shall be capable of interrupting the rated power
with recovery voltage equal to the rated maximum line to line
service voltage at rated frequency and at a power factor not
220.127.116.11 The circuit breakers shall also be capable of satisfactory operation
even under conditions of phase opposition that may arise due to
faulty synchronizing. The maximum power which the breaker can
satisfactorily interrupt under phase opposition shall be stated in the
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18.104.22.168 The operating duty of the circuit breaker shall be as specified under
Clause - 2.4.12 of specific technical requirement for breakers.
1.4.2 Temperature Rise:
22.214.171.124 The temperature rise and the maximum temperature on any part of
the breaker when in service under continuous full load conditions
and exposed continuously to the direct sun-rays shall not exceed
the permissible limits as per relevant ISS. When the standard
specifies the limits of temperature rise, this shall not be exceeded
when corrected for the difference between ambient temperature at
site and the ambient temperature specified in the relevant
specification. The correction proposed shall be stated in offer and
shall be subject to the approval of the purchaser.
1.4.3 General Features of Circuit Breakers:
126.96.36.199 The circuit breakers shall be suitable for outdoor operation under
the climatic conditions specified in section-II of this specification.
188.8.131.52(a) The circuit breakers operating mechanism shall have two nos. of
tripping coils and one no. of closing coil for both 66 kV SF6 Gas CB
for better reliability. There shall be separate contactor for each coil.
184.108.40.206 Exposed live parts shall be placed high enough above ground to
meet the requirements of local safety codes.
220.127.116.11 All similar parts, particularly removable one and shall be
interchangeable with one another.
1.4.4 Insulation of the Circuit Breaker:
The insulation to ground, the insulation between open contacts and
the insulation between phases of the completely assembled circuit
breaker shall capable of withstanding satisfactorily die-electric test
voltages corresponding to BIL specified in Clause – 2.4.2 of this
1.4.5(a) The minimum clearances in open air shall be as under in case of
Minimum clearance between phase : As per relevant IS.
Minimum clearance between live parts : As per relevant IS.
and grounded objects.
1.4.5(b) Adequate clearance in air shall be provided between phase and
from phase to ground. The clearance shall be such that the breaker
shall withstand the BIL specified in the specification. The minimum
clearance from live parts to ground level shall not be less than 4000
mm – including plinth height as 300 mm.
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1.4.6 Contacts of Circuit Breaker:
18.104.22.168 The main contacts shall have adequate area and contact pressure
for carrying the rated currents and the short time rated breaking
currents of the breaker without excessive temperature rise.
Contacts shall be easily replaceable and shall have a minimum of
movable parts and adjustments. The main contacts shall be first to
open and last to close so that burning of the contact may be
1.4.7 Operating Mechanism of Circuit Breakers:
22.214.171.124 Circuit breakers shall be power operated by a motor compressed
spring charging mechanism; the mechanism will be trip-free
electrically and mechanically. The mechanism shall be strong, quick
in action and shall be removable without disturbing other parts of
the circuit breakers. All the working parts in the mechanism shall be
of corrosion resistant materials and all bearings which require
greasing, shall be equipped with pressure grease fittings. The
mechanism and breaker shall be such that the failure of any spring
will not prevent tripping and will not cause tripping or closing.
126.96.36.199 The circuit breakers shall be designed for remote control from the
control room and there shall be provision for manual operation of
circuit breakers during maintenance and for local tripping and
closing by normal means.
188.8.131.52 The circuit breaker shall have a mechanical ‘ON-OFF’ indicator in
addition to facilities for remote electrical indicator.
184.108.40.206 The operating mechanism along with its accessories shall be
suitable for electrical operation and shall be mounted in a weather
proof cabinet with hinged doors located near the breakers. The
cabinet shall be suitable for IP 55 degree of protection. The
operation shall be possible from ground or necessary HDG
stand/platform of suitable height maintaining all safety clearance with
live parts shall be supplied as a part of breaker. The local control
switch and the breaker position indicator shall be provided in this
cabinet, which shall be free standing and supported by suitable
arrangement. The control circuit shall be designed to operate on
D.C. as specified in section-II of this specification. The closing and
opening coils shall be designed to operate satisfactorily at any
control voltage from 85% to 110% & 70% to 110% of the normal
voltage, respectively. A heater of adequate capacity with thermostat
shall be provided in the cabinet to avoid moisture condensation.
220.127.116.11(a) The terminal block shall of 1.1 KV voltage grade & shall be with
stud type connections instead of with screw types connections.
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1.4.8 Auxiliary switches:
18.104.22.168 A minimum number of 6 NC + 6 NO Auxiliary switches contacts
shall be provided on each circuit breaker for use in remote
indication control scheme of the circular breakers and for safety
interlocking. Special contacts for use with trip coils and auto
reclosing operation shall also be provided. Provision shall be made
for adding more auxiliary switches, if required. Auxiliary switches
shall be placed in weatherproof galvanized casing and current
rating of switches shall be mentioned in the offer.
1.5 BUSHING & INSULATORS:
1.5.1 The porcelain insulator used in manufacturing the bushings shall be
homogeneous, free from laminations, cavities and other flaws or
imperfection that might affect the mechanical or dielectric qualities.
All bushings of identical ratings shall be interchangeable. The
insulators shall conform to the latest edition of IS: 3447 or other
equivalent standard. The puncture strengths of the bushings shall
be greater than their flashover values. The bushings shall be
entirely free from external and internal corona. The protected and
total creepage distance of the bushings shall be suitable for heavily
polluted atmosphere. The minimum creepage distance of the
insulator shall be 1810 mm suitable for heaving polluted
atmosphere. The compressive and cantilever strength shall
conform to the relevant IS.
1.6 TERMINAL CONNECTORS AND EARTHING TERMINALS :
1.6.1 Compression joint type terminal connectors suitable for single or
twin ACSR panther/zebra/Moose as indicated in Schedule – A
of respective tender, shall be supplied and they shall be suitable
for both vertical and horizontal connections of the Transmission line
conductor or station bus bar. Suitable terminal earth connectors
(two Nos.) for earthing connections shall also be supplied. The
drawings for these connectors shall be submitted. SS bolt for
connector shall be provided with two Nos. of SS nuts (including lock
nut & one SS washer.
1.7.1 All control wiring, electric motors and accessories shall be protected
against fungus growth and other harmful effects due to tropical
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1.8.1 All ferrous parts of breakers and bolts, nuts etc. shall be hot-dip
galvanized as per latest edition of IS: 2629. Support structure’s
galvanizing shall be done as per IS 4843 (latest edition). Electro
galvanized bolts nuts, & washers are also acceptable.
1.9.1 Interior and exteriors of tanks, mechanisms, enclosures, cabinets
and other metal parts shall be thoroughly cleaned to remove all rust
scales, corrosion and other adhering foreign matter, steel surfaces
in contacts with insulation oil, as far as possible shall be painting
with not less than two coats of heat resistant, oil insoluble,
insulating varnish light-grey paint shade 631 as per IS:5 shall be
selected to withstand tropical heat and extremes of weather.
1.10 TEST AND TEST REPORTS:
1.10.1 Reports of following type tests carried out in NABL / Govt. approved
laboratory within five years prior to expiry of validity of offer, as per
IS: 13118 / IEC 62271-100 for A C circuit breakers shall be
submitted along with the offer :
(i) Lightning impulse withstand voltage test
(ii) Power frequency voltage withstand voltage test. (Dry as well as Wet)
(iii) Temperature rise test.
(iv) Measurement of resistance of main circuit
(v) Short time current withstand and peak current withstand Test
(vi) Mechanical endurance test
(vii) Duty cycle & Single phase short circuit test.
(viii) Out of phase making and breaking current test.
(ix) Capacitor current switching test for isolated neutral capacitor
(x) Line charging current switching test
(xi) Cable charging current switching test
(xii) Short line fault duty test
(xiii) Degree of protection test on cubicles
IMPORTANT NOTE: In case of non-submission of some of the type test reports, the
bidder shall confirm the submission of same before commencement of supply,
without affecting delivery schedule, from NABL accredited laboratory, free of cost.
In absence of this confirmation, the offer will be evaluated as non submission of
type test report.
1.10.2 Routine tests as per the latest edition of IS: 13118/IEC 62271 for
circuit breakers shall be carried out on each circuit breaker. All the
acceptance tests in presence of GETCO representative shall be carried
out on circuit breakers selected from offered lot.
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1.10.3 In addition to above, speed curves for each breaker shall be obtained
with the help of a suitable operation analyzer to determine the breaker
contact movement during opening, closing, auto-re-closing and trip free
operations under normal as well as limiting operating conditions (of
control voltage) The tests shall show the speed of contacts directly at
various stages of operation, travel of contacts, opening time, closing
time, shortest time between separation and meeting of contacts at
make-break operation and dynamic contact resistance measurement
1.10.4 The test reports for type tests and routine tests in respect of
associated items such as spring charging motors, instruments,
pressure switches, relays, terminal connectors, etc. as per the latest
edition of the relevant IS shall be supplied by the bidder. All the
routine test reports for all the breakers and for all the
insulators utilized shall be submitted with inspection report.
1.10.5 All tests reports for acceptance / routine tests shall be submitted in
spiral bound volume and got approved from the purchaser before
dispatching the breaker.
1.11 SPARE PARTS:
1.11.1 Bidder shall submit list of spares recommended by him for
satisfactory operation of the circuit breakers for first five years and
rate for each spare shall also be quoted. The purchaser will decide
the actual quantity of spare parts to be ordered on the basis of the
prices of the spare parts, quoted by the bidder.
1.12 TECHNICAL & GUARANTEED PARTICULARS :
The bidder shall furnish all guaranteed technical particulars as
called for in section - IV of this specification. Particulars which are
subject to guarantee shall be clearly stated offers not containing this
information will not be considered.
Deviation against any clause of this technical specification shall be
clearly described separately.
1.13 INSTRUCTION MANUALS:
1.13.1 Three copies of operation, maintenance and erection manuals in
English language shall be provided in each circuit breaker supplied.
The manuals shall be bound volumes and shall contain all the
drawings and instructions required for erection, operation and
maintenance and in addition the following particulars:
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a) Marked erection prints identifying the component parts of the circuit
breakers and current transformers as dispatched with the assembly
b) Details dimensions, assembly and description of all the components
and catalogues for operation of the circuit breaker and accessories.
c) List of recommended spare parts of circuit breaker.
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TECHNICAL SPECIFICATION FOR
66 kV SF6 GAS CIRCUIT BREAKER
SECTION – II
This section covers the specific technical requirements, climatic and
Isoceraunic conditions and system particulars for which the circuit
breakers shall be offered as per the General Technical
Requirements given in Section-I of this specification and the
schedule of requirements specified herein.
2.2 CLIMATIC & ISOKERAUNIC CONDITIONS:
2.2.1 The climatic conditions under which the breaker shall operate
satisfactorily are as follows:
a) Maximum ambient temperature of air
in shade (0
b) Minimum ambient temperature of air
in shade (0
c) Maximum daily average ambient
d) Maximum yearly average ambient
e) Maximum relative humidity (%). : 95 %
f) Average number of thunderstorm
days / annum.
g) Average annual rainfall (Cm.) : 150 cm.
h) Maximum wind pressure (Kg/m2) : 150 kg/M2
i) Height above mean see level (m). : Not exceeding
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2.2.2 All breakers offered shall be suitable for continuous satisfactory
operation at the full rated capacity under the above climatic
2.2.3 Since the sub-station may be near seashore or Industrial area, the
breaker offered shall be suitable for heavily polluted atmosphere.
2.3 SYSTEM DETAILS:
i) Nominal system voltage : 66 kV
ii) Maximum rated voltage : 72.5 kV
iii) Frequency : 50 Cycle / Second.
iv) Number of phases : 3
v) Neutral Earthing : Solidly earthed.
vi) Auxiliary power supply : 1) 240 Volts 1-φ & 415
Volts 3-φ, 50 Hz A.C., with
the variation of frequency
± 5% and voltage + 10% &
2) 110 Volts or 220 Volts
2-wire D.C. supply subject
to variations of ± 10%.
2.4 The circuit breakers shall be complete with following technical
11) Number of Poles : 3
2) Basic Insulation level
1) 1.2/50 Microsecond
impulse withstand voltage.
2) On Minute Power
140 kV rms
3) Rated normal current : 1600 Amps.
3a) Rated symmetrical breaking
capacity at highest system
: 3000 MVA
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4) Rated short circuit breaking
: 31.5 kA rms
5) Rated duration of short circuit : 3 second.
6) Total break time for any
current upto the rated
: 3 cycles
7) Closing time. : Not more than 10 cycles.
8) Rated characteristics for short
: As per IS: 13118 / IEC
9) Rated transient recovery
voltage for terminal fault.
: As per IS: 13118 / IEC
10) Rated line charging current
: 10 Amps.
11) Rated short circuit making
: 78.75 kAp
12) Rated operating duty : O–0.3 S–CO–3 M–CO
13) Rated SF6 Gas pressure (AT
: 5 kg / Cm2
14) Total creepage distance for
heavily polluted atmosphere.
: 1810 mm min.
15) Live part to plinth level
clearance in mm
: 4000 mm
2.5 EARTH QUAKE & WIND DESIGN LOADS:
Each circuit breaker including its supporting structure shall be
designed to withstand required earthquake acceleration of 0.08 x 2
g and with wind loads of 150 Kg/m2 on the projected area (non-
simultaneous) without damage to component parts and without
impairment of operation.
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TECHNICAL SPECIFICATION FOR
66 kV SF6 GAS CIRCUIT BREAKER
SECTION – III
GENERAL DESIGN OF 66 kV SF6 GAS CIRCUIT BREAKER
3.2 GENERAL DESIGN FEATURE OF SF6 BREAKER:
3.2.1 SF6 Gas Circuit breaker shall consist of three identical single
phase units with common Spring operating mechanism suitable
for specified duty. Separate SF6 Gas Cylinder along with suitable
gas system, incorporating required gas stop valves, copper piping
of suitable size shall be provided. Required pressure switches as
stated in Cl. 22.214.171.124 shall be provided. Gas pressure gauge shall
be fitted on the common feed pipe to monitor the pressure of SF6
gas in the interrupter.
Absorbent shall also be provided in each interrupting unit to keep
the SF6 gas dry & absorb the decomposed product of SF6 gas,
formed during arcing.
Bidder shall give complete constructional details for SF6 gas
circuit breaker offered by them. The insulation level of porcelain of
the circuit breaker shall be so coordinated with that of the breaker
that flashover shall occur externally to the breaker.
3.2.2 In case of SF6 circuit breaker, it shall be possible to arrange for
either automatic tripping of the circuit breaker or tripping of circuit
breaker on fault and will be automatically locked when the
pressure in the individual interrupter reaches below the limit
value. Arrangements shall be made to prevent closing of the
breaker due to leakage of gas passing through the closing valve
without a positive impulse from the closing coil.
3.2.3 The SF6 gas used in the circuit Breaker shall comply in all
respect with the provisions of the latest edition of relevant
3.2.4 Inter Locks :
3.2.4(a) Pressure switches with the required pressure fitting must be
incorporated to ensure safety of breaker operation when SF6 gas
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pressure goes below the specified pressure range due to
leakage, the trip coil circuit & closing coil circuit must be cut-off.
The pressure switch shall generally be temperature compensated
gas pressure switch having two micro-switches, operating at
different pressures one for low pressure alarm and other for low
3.2.4(b) Additional dedicated pressure switch with 4 poles for Normal, Low gas,
Lockout, etc shall be provided for SCADA remote operations. L/R switch
shall have spare contacts.
3.2.4(c) Limit switch for motors shall be provided with 4 NO and 4 NC contacts.
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SECTION – IV
SCHEDULE OF GUARANTEED TECHNICAL PARTICULARS
FOR 66KV SF-6 GAS Spring operated CIRCUIT BREAKERS
(TO BE FILLED IN & SIGNED BY THE BIDDER)
1. Name of Manufacturer :
Type Designation of CB
Type designation of Spring mechanism
(as per Mech. Endu. test report)
3. Governing Standard :
4. Rated Voltage (KV) :
5. Maximum continuous rated service
6. Frequency (Hz) :
7. Whether outdoor breaker offered (Yes /
8. Nominal current rating
i) Under standard condition. (Amp)
ii) Under site condition (Amp).
iii) Type test reports submitted of
9. Short time current rating (kA) for 3
10. Maximum temperature rise over ambient
temp. due to rated current in main
contacts measured after breaking test.
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11. Rated short circuit breaking current
a) Rated short circuit current (AC
component) (KV rms).
b) Percentage DC component
c) Asymmetrical breaking current
(including DC component (KA rms).
d) Rated symmetrical breaking capacity
in MVA FOR SF6 CB
12. Making capacity (kA Peak) :
13. Total breaking time (Milli-seconds) :
a) For interruption of 10% of the rated
b) For interruption of 30% of the rated
c) For interruption of 60% of rated
d) For interruption of the full rated
14. Arcing time ( milliseconds) :
Making time (milliseconds)
Rated closing time (milliseconds)
Rated opening time (milliseconds)
16. Minimum reclosing time at rated
interrupting capacity from the in fault of
the trip coil energisation (Millisecond)
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17. A) Minimum dead time
a) 3 phase reclosing (Milliseconds).
b) Limit of adjustment of dead time
for 3-phase reclosing.
B) Whether restrike free and trip free. (IS
/ IEC applicable may be stated).
18. Date on restriking voltage for 100%, 50%
& 30% rated capacity
a) Amplitude factor (max)
b) Phase factor (max)
c) Natural Frequency (Hz)
d) Rate of rise of restriking voltage
19. Maximum interrupting capacity under
phase opposition condition (MVA).
20. Maximum line charging current breaking
capacity without over voltage exceeding
2.5phase neutral voltage (Amps.)
21. Maximum line charging current breaking
capacity corresponding over-voltage
a) On supply side.
b) On line side.
22. Maximum cable charging current
breaking capacity & corresponding over-
voltage recorded in test.
a) On supply side.
b) On line side.
23. Maximum shunt capacitor Bank switching
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24. Maximum breaking capacity on kilometric
25. Maximum over-voltage on switching
transformers on no load & the charging
26. Dry 1 Minute power frequency test
withstand voltage, for complete circuit
a) Between line & Grounded parts (kV
b) Between line with breaker contacts
open (kV rms)
27. Wet 1-minute power frequency withstand
voltage for complete circuit breaker
a) Between line terminal & grounded
parts (kV rms)
b) Between terminals with breaker
contacts open (kV rms)
28. 1.2/50 Micro-second wave lightning
impulse withstand test voltage for
complete circuit breaker, as per type test
a) Between line terminal and ground
b) Between terminal with circuit breaker
contacts open (kV peak).
SUPPORTING INSULATORS :
29. Make & Type :
30. Insulation Class :
31. Visible Corona discharge voltage :
32. Wet 1-minute power frequency flashover
voltage (kV rms).
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33. Dry 1-minute power frequency flashover
voltage (kV rms)
34. 1.2/50 micro-second impulse flashover
voltage (kV peak)
35. Total creepage distance for heavily
36. Minimum clearance in air
a) Between phases (mm)
b) Live parts & earth (mm)
c) Live parts to Plinth level (mm).
Permissible safe cantilever loading on
installed porcelain (kg.m)
Permissible safe compressive strength of
37. No. of poles per circuit
38. Breaks per pole (Nos). :
39. Total length of breaks per
40 Type of main contacts :
41. Material of main contacts :
42. Whether main contacts silver
43. Thickness of silver coating on
main contacts (mm).
44. Contact pressure on main
45. Type of arcing contacts :
46. Contact pressure on arcing
47. Type of auxiliary switches :
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48. Material of switch contacts :
49. Whether contacts silver plates
50. No. of auxiliary switch
contacts operating with all
three poles of breaker
a) Which are closed when
breaker is closed.
b) Which are open when
breaker is closed
51A No. of spare auxiliary switch
a) Which are closed when
breaker is closed.
b) Which are open when
breaker is closed.
B Details of SF6 Gas pressure
switch and its setting for low
pressure alarm and low
52. No. of operations possible
a) At full rated interrupting
b) At 50% of rated
c) At 100% of rated current
d) At 50% of rated current
53. Details of foundation :
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54. Type of operating mechanism
(motor operated spring
c) Control voltage aux.
54a Details of spring charging motor
ii) Rated supply voltage
iv) Max time for charging
55. Tripping & closing circuit
voltage (V). (110 V/220 V.)
As per requirement.
56. Power required for trip coil (in
57. Power required for closing coil
58. Weight of 3-φ breaker
complete with operating
insulators, frame work etc.
59. Impact loading for foundation
design to include dead load
plug impact value on opening
it maximum interrupting rating
in terms of equivalent static
60. Weight of heaviest package
(Kgs) space requirements
(Length, Width, Height).
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61. A) Details of Gas pressure
switch and its setting for
low pressure alarm and
low pressure cut-out.
62 SF6 GAS DETAILS:
a) Rated SF6 Gas
b) IS / Equivalent standard
applicable for SF6 Gas.
c) Quantity in each pole
d) Total quantity
e) Spare gas quantity (%)
63 Terminal connector
(Bimetallic compression type)
64 Seismic level (g) :
SEAL OF THE FIRM SIGNATURE OF TENDERER
26. GETCO/E/06TS – CB/R3 May12
Page 26 of 26
SECTION – V
List of documents attached with technical bid:
Bidder shall invariably attach the following documents and clearly marked
and duly flagged in technical bid. In absence of these documents offer will
be evaluated as a non submission.
Particulars of document Whether
attached the with
1 Drawings in AutoCAD format
2 Drawings hard copies as indicated in
3 Manual in PDF format
4 QAP for manufacturing process in SOFT
5 QAP for manufacturing process in Hard format
6 FQP in SOFT format
7 FQP in Hard copy
8 Type test Reports in hard copies
a for breaker
b for clamps & connectors
9 Confirmation regarding type tests as per
clause no. 1.10(a) page no. 10 –
10 Guaranteed Technical Particulars, completely
11 Any other essential documents
SIGNATURE OF BIDDER COMPANY’S ROUND SEAL