Sunday, June 18, 2017
Creeping in Energy Meters:
In some energy meters a slow but continuous rotation of the disc is obtained when the pressure coils are energized and there is no load current passing through the current coil i.e. current coil is not energized.The main reason for creeping is over-compensation the aluminium disk to over come the static friction of disk and another reason is over voltage across the shunt magnet.Due to this creeping consumers suffers from high tariff. This may be due to incorrect friction compensation to vibration, to stray magnetic field or to the fact that the supply voltage is in excess of the normal voltage. This unwanted effect is called as "creeping in energy meter".
Read Here : How Energy Meter Works?
How to reduce creeping error in energy meter?
To prevent such creeping of the meter two holes or slots are cut in the disc on opposite sides of the spindle. The disc tends to remain stationary when one of the holes comes under one of the poles of the shunt magnet. In some cases a small piece of iron wire is attached to the edge of the disc. The force of attraction of the brake magnet upon this iron wire is sufficient to prevent the creeping of the disc under no load condition.