What are the Errors and their Adjustments in 1Φ energy meter
Errors and their Adjustments in 1Φ energy meter Energy meters should give correct readings over a period of several years under normal use conditions. Some of the common errors in energy meter and their remedial measures are discussed below. 1. Phase Error: It is necessary that the energy meter should give correct reading on all power factors, which is only possible when the field setup by shunt magnet lags behind the applied voltage by 90 o . But the flux due to shunt magnet does not lag behind the applied voltage exactly by 90 o because of winding resistance and iron losses. Adjustment: The flux in the shunt magnet can be made to lag behind the supply voltage by exactly 90 o by adjusting the position of shading band (or shading ring or shading coil) placed round the lower part of the control limb of the shunt magnet. This adjustment is known as lag adjustment or power factor adjustment (or power factor compensator ). 2. ...