IS 11426 : Part 1 : 2006 Alternating Current Precision Electricity Meters for Testing Purposes - Part 1 : Requirements for Electro-Mechanical Meters

1 Scope

1.1 This standard (Part 1) covers the requirements of single phase two-wire and poly phase, 3 phase3 wire/3 phase 4 wire electro-mechanical meters requiring a degree of accuracy of 0.5. Performance characteristics will be suitable for the purpose of testing electro-mechanical meters with an accuracyof not better than class 2. The meter may be either whole current or transformer operated. It does notapply to poly phase meter in which the principle of measurement requires balanced conditions of load or supply.

1.2 This is applicable to meters constructed to register MWh/kWh and (or alternatively) the number of revolutions of the meter rotor both for fixed and portable meters. Meters of metering equipments may have single or multi-current and single or multi-voltage ratings.

1.3 Since manufacture of such electro-mechanical meters has almost ceased and with the growing useof more precision static meters [to be covered in IS 11426 Part (2)], the requirements covered underthis standard are merely restricted to continued usage of old meters by utilities.