SYSTEM OF SUPPLY :
The declared frequency of A.C. supply is 50 Hz
The declared voltage of A.C. Supply is as follows:
a. Low Voltage - single phase, 230 V, between phases and neutral.
b. Medium Voltage - Three phase or Two phase 400 Volts between phases.
c. High tension supply - Three phase at 11 KV or 33 KV.
d. EHT supply - Three phase at 132KV, 220KV or 400KV or two phases at 132 KV/220 KV for existing Railway Traction.
The voltage of supply shall be determined by the engineer depending on the contract demand of the consumer. The supply voltage for the contract demands shall normally be as follows.
a. For contract demand not exceeding 5 KW or 5.55 KVA, excepting in the case of irrigation pumps and agricultural services, supply shall be at single phase, two wires and 230 volts,
b. For irrigation pumping and agricultural service load of 3 BHP and below, supply shall be at single phase, two wire and 230 volts, between phase and neutral, or 3 phase, 3 or 4 wire and 400 volts between phases,
c. For load above 5 KW or 5.55 KVA up to and including 70 KVA, supply shall be at 2 phase, 3 wires or 3 phases, 3 or 4 wires at 400 volts between phases.
For contract demand above 70 KVA but below 555 KVA, supply shall be at 3 phase, 3 wires at 11000 volts. For contract demand of 555 KVA and above but below 1110 KVA, supply may be given at 3 phase, 3 wires at 11000 volts or 33000 volts depending on the convenience of the licensee;
1. For contract demand of 1110 KVA and above but below 5000 KVA, supply shall be at 3 phase, 3 wires at 33000 volts;
2. For contract demand of 5000 KVA and above, supply shall be at 3 phase, 3 wires EHT;
Power Factor :
The consumer shall so arrange his installation that the average power factor of his load during any billing period is not less than 90%. Power factor penalty shall be levied if there is a breach of the aforesaid requirement and supply of power may be disconnected if the power factor falls below 60%;
Balance of Load :
A consumer taking two or three phase supply shall balance his load in such a way that the difference in loading of each phase does not exceed 5% of average loading between the phases.