(1) The declared frequency of the alternating current (AC) shall be 50 Hz. The Licensee shall maintain the frequency within the frequency band as may be notified by the Authority from time to time.
(2) The voltage levels for supply shall be as under:- [PART III DELHI GAZETTE : EXTRAORDINARY 61
(i) Low Tension (LT)
(a) Single Phase: 230 volts between phase and neutral.
(b) Three Phase: 400 volts between phases.
(ii) High Tension (HT) - Three Phase: 11 kV between phases
(iii) Extra High Tension (EHT) - Three Phase: 33kV or 66kV between phases.
(3) The Licensee shall design, install, maintain and operate a distribution system in conjunction with the transmission system.
(4) The voltage at the point of supply shall remain within the limits as specified hereunder:
(i) In the case of low tension, 6%.
(ii) In the case of high tension, + 6% to - 9%.
(iii) In the case of extra high tension, + 10% to -12.5%.