Bharat Heavy Electricals Watthour Meters

1 This standard specifies static watthour meters of accuracy class 1 and 2, for the measurement of alternating-current electrical active energy of frequency in the range 45~Hz to 55 Hz for single-phase and threephase balanced and unbalanced loads. It applies to their type tests, routine tests and acceptance tests. A watthour meter provided with a number of registers, each operative at specified time intervals
corresponding to different tariffs.