NATIONAL ALUMINIUM COMPANY LIMITED - Rites

Internal control wiring shall be by 1100V V grade PVC insulated, single core stranded copper
conductor of minimum cross section 2.5 sq.mm. for CTs and space heater circuits and 1.5
sq.mm for other circuits. For CT secondary wiring, disconnecting type terminal blocks (CAD
type) shall be considered. .
For external terminations, , DIN rail mounting type bakelite type terminal blocks shall be used
complete with insulated barriers, stud type terminals, washers, nuts and lock nuts and
identification strips. Power and control terminals segregated.
Other accessories
Following items shall be provided for the MCCs under the scope of the Bidder:
Breaker lifting/handling trolley (for ACBs) : 1 No. per MCC Room
Breaker racking handle (for ACBs) : 4 Nos. per MCC Room
Panel key (if applicable)
: 5 Nos. per MCC Room
Selection of power components & wiring for continuous duty cage motor drives is given below:
Motor
Rating
at S1
Duty
(KW )
Up to
3.7
5.5
7.5
Minimu
m
rating
of
MCCB
*
*
*
11 *
15 *
18.5 *
22 *
30 *
37 *
45 *
55 *
75 *
90 *
110 *
125 *
135 *
160 *
Technical Specification:Sec-6, Electrical
Minimum
rating of
contactor
(AMPS) AC3
duty
25
40
40
Minimum size for internal
power connections
Copper
wire
(sq.mm)
Aluminium flat
(mm x mm )**
*Minimum rating of MCCB shall be selected to achieve type ‘2' protection.
4
4
6
40 6 -
63 10 -
-
-
-
Minimum size of
power cable
Aluminium
(sq.mm)
4x 2.5(copper)
4x 2.5(copper)
4 x 6
4 x 16
4 x 16
63 16 12 x 2 3.5 x 35
63 16 12 x 2 3.5 x 35
100 25 12 x 2 3.5 x 70
100 35 15 x 3 3.5 x 70
160 50 15 x 3 3.5 x 95
160 70 20 x 3 3.5 x 120
200 95 20 x 5 3.5 x 185
400 20 x 5 3.5 x 185
400 30 x 5 2(3.5 x 120)
400 40 x 5 2(3.5 x 120)
400 40 x 5 2(3.5 x 120)
400 40 x 5 2(3.5 x 185)
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