NATIONAL ALUMINIUM COMPANY LIMITED - Rites

Outgoings : MCCB TPN of 32 A : 10 Nos.
220V DC Emergency LDB (DCELDB)
The DCELDB used for emergency lighting distribution shall be industrial heavy duty type
suitable for 2-wire 220V DC operation, and shall have a DC double pole power contractor and
requisite number of auxiliary contractors and timers and outgoing feeders protected with DP
MCBs of suitable ratings.
The incomer shall be of double pole load break design suitable ffor
or operating on 220V DC. The
enclosure shall be made of 2 mm thick sheet steel and shall have requisite number of cable
glands and terminal strips for incoming and outgoing cables. The control circuit voltage shall
be of 220V DC.
The DCELDBs which feed aall
ll the emergency lighting points shall be automatically switched on
the event of power failure through a separate circuit which sense under voltage of normal AC
supply at the specified location. These emergency lighting fittings shall glow for a preset tim time
and shall be switched OFF automatically through a time relay in case the normal AC power
supply is not restored within that time.
Feeder configuration of DCELDB shall be as follows:
Incomer : MCCB, DP (63 A) – 1 No.
Outgoing : MCB, DP (10 A) – 16 Nos.
Supply of battery, battery charger(FC & FCBC, DCDB for 220V DC system shall be in bidder’s
scope.
415 V switch outlets
Switch socket outlets and plugs for 415 V, 33-phase
phase circuits shall be of four four-pin (three pole and
one earth), non-reversible reversible typ type enclosed in dust-proof proof 2 mm thick sheet steel enclosures. The
socket outlets shall be provided with fuses and shall have isolating switch interlocking as per
IS:4160 such that it can be switched ‘ON’ only when the plug has been inserted and plug can
be provided rovided for the socket outlets. The isolating switches shall be of category AC 23
conforming to IS 13947 (Part 3). The socket outlet shall be suitable for terminating aluminum
conductor cables either directly or through GI pipe and shall be provided with c ccompression
type lugs. The socket outlet shall be supplied with metal clad plug. The socket outlets and
plugs shall have porcelain base and shall be of 32A rating.
Weather-proof proof enclosure shall be used for outdoor installation. Inscription plate shall be
provided indicating the voltage rating for the switch outlet.
240 V switch socket outlets
Socket outlet for 240 V supply shall be of 33-pin
(two-pole pole and one earth) nonreversible, metal-
clad, dust-proof, proof, industrial type suitable for horizontal insertion generally as per IS 1293. 240 V
Technical Specification:Sec-6, Electrical
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