System voltage 415 V +/- 10%, 3 Phase, 4 wire AC
2. Frequency 50 Hz +/- 3%
3. Fault level Shall be designed for fault level of 50 KA for 1 sec
4. Grounding Solidly grounded neutral system
5.
Insulation level
a) Power circuit
b) Control circuit
2.5 KV / 1 minute
1.5 KV / 1 minute
6. Main bus bars
Shall be designed to carry continuous current rating of 1.2
times of incomer ACB unitâ??s continuous current rating and
STC of 50 kA for 1 sec. Temperature rise, short circuit
design shall be as per IS 8623.
Max. Current density for the material of bus bar shall be as
follows:
Copper: 1.6 Amp/Sq.mm
Aluminum: 0.8 Amp/Sq.mm (For Sl. No. 12 PCC)
