purchase & stores division - ISRO

3. VACUUM CIRCUIT BREAKER Bus Coupler RMU
Application: - Bus coupler at 11kV bus
Enclosuer: Metal Clad; IP - 54; Internal arc tested; Fully
insulated. Fully compartmentalized sheet steel enclosure with
automatic safety shutters, G.I foundation bolts with provision for
terminating 1 x 120 sq.mm XLPE cable using Raychem heat
shrinkable type end termination kit.
Service - Indoor
Paint - Light Admirality Grey - 631 IS5 Powder coated smooth
glossy finish.
Rated voltage - 12 kV
Rated Frequency - 50 Hz
Rated continuos current - 630 amps
Rated interrupting current - 26.3 kA
Rated making current - 65.5 kA
Rated short time current for 3 sec. - 26.3 kA
Operating duty - 0 - 0.3 sec - CO 3 min - CO
Power frequency withstand voltage - 28 kV
Impulse withstand voltage - 75 kV
Busbar rating - 120 % of rated continuos current
Operation -
Spring closing mechanism - Electrical motor operated OR
Solenoid
Breaker Closing - Manual & Electrical through TNC switch.
Shunt trip coil - 24 V d.c
Safety interlock & locking facility - Required
Breaker panel Indication:-
Breaker ON - RED
Breaker OFF - GREEN
Accessories.
Mechanical counter, Space Heater with Thermostat, Fuse and
ON/Off switch
Aux. relays for remote trip/indication for PC interface etc Cubicle
illumination lamp CFL 18 W retrofit type 230 V a.c
T - N - C switch
Anti pumping contactor
Mimic diagram: An operating mimic diagram shall be provided
on the front side of each cubicle.
Enclosure: IP 54. Identical for inter facing above two Panels
4 Earthing system
a. Copper Plate earthing station as per Drg. Enclosed 6 Nos
b. G.I Pipe earthing station as per Drg. Enclosed 10 Nos
c. Out door yard grid earthing as per Drg. Enclosed 4 + 16
d. Supply & laying of Copper flat for earthing 40 x 6 mm 100 Mtrs
e. Supply & laying of G.I flat for earthing 35 x 4 mm 500 Mtrs
5. Monitoring & Control
a. PLC for complete Sub - Station Automation 1 No
1 No For Bus
Coupler
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