Tender Document Volume - 2 - BPDB

Power Frequency (rms.)
(For 1 mm.)
: 22 KV
3) The rated service voltage shall be of 6.6 KV.
4) The current rating of the main bas bars shall not less than the rating of
the unit auxiliary transformer and rating of the associated connections shall be
determined by the Contractor.
(5) The short time three phase fault level rating for one second of the switch
gear shall be of 40KA (rms).
4.4.3 Construction And Fittings
The 6.6 KV common switchgear shall be designed and constructed as same as
those for 15 KV generator switchgear specified in Section 4.3.
4.4.4 Circuit Breaker
The circuit breaker shall be of SF 6 gas or vacuum type.
The circuit breaker shall comply with the requirements of IEC 56 and with the
relevant requirements of this specification.
All circuit breakers shall be identical in arrangement and shall be interchangeable.
- Rated Voltage : 6.6 KV
- Rated Current : 1250A
- Interrupting Current : 40 KA (rms)
Only fully type tested circuit breakers complying with IEC 56 will be considered,
and a statement as to the availability of certificates of all such type tests including
impulse tests on identical or similar circuit breakers shall be submitted with
Tender.
4.4.5 Composition Of Cubicles
(1) Incoming Circuit Breaker Cubicle for unit(s)
- Circuit breaker : One(1)
1250 A, 40 KA (rms)
- Current transformer :Three(3) units
600/300- 5A, 40 VA
- End terminal :One(1) lot
- Ammeter with selector switch :One(1) set
- Protective relays :One (1) set
- Control switch, etc. :One(1) lot
Ghorasal 200 MW to 300 MW Gas Turbine Peaking Power Plant Project (Vol-2 of 3)
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