List any four errors in induction type energy meter. Give method of compensation for each.

1 Answer

Answer :

Errors in Induction Type Energy Meter with their Compensation: 

1) Error due to friction: This error can be compensated by the additional shading band provided on the shunt electromagnet. 

2) Phase or low p.f. error:To overcome this error the shading band is provided on the central limb of the shunt electromagnet. 

3) Error due to temperature variation: The effects of temperature changes on the driving and braking system tend to balance each other, hence no need of compensation. 

4) Error due to variation of frequency: The frequency should be kept constant. 

5) Creeping error: This error can be compensated by providing two small holes on the disc diametrically opposite side.When the hole comes under the pole of a shunt magnet,the disc stops running. 

6) Error in Registration: This error can be compensated by adjusting the braking magnet or changing registering system. 

7) Speed error: This error can be compensated by readjusting the compensating mechanism. 

8) Overload error: This error can be compensated by providing a ‘flux diverter’ to the current magnet. 

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