Induction type energy meter

in this article we will learn about the induction type energy meter. we will learn about the application of induction type energy meter.
induction type energy meter, adjustment of energy meter, application of energy meter

Induction type energy meter

Energy is total power delivered or consumed over a time interval,
Energy = power x Time
Electrical energy developed as work or dissipated as heat over an interval time t
Energy is an integrating type of instrument used for measurement of energy in domestic and industrial AC circuits.
Single phase induction type energy meter
Construction of induction type energy meter
In induction type energy meter mainly four part
induction type energy meter, adjustment of energy meter, application of energy meter

1. Driving system

Consists of two electromagnets made of silicon steel laminations.
Coil of one of the electromagnet (shunt magnet) is excited by load current known as current coil.
Coil of second electromagnet (series magnet) is connected across supply and carries a current proportional to voltage known as pressure coil.
Copper shading bands whose position is adjustable are provided on central limb to bring the flux exactly in quadrature with the applied voltage.

2. Moving system

Consist of an aluminum disc mounted on a light alloy shaft positioned in the air gap between magnets.
Shaft is pivoted on jewel bearings and a pinion engages it with counting or registering mechanism.

3. Breaking system

Breaking torque is required to control the speed of moving system. A permanent magnetism positioned near the edge of the aluminum disc to provide breaking torque.
This magnet induces eddy currents that produce the braking torque proportional to the speed of moving system.

4. Registering or counting mechanism

Records continuously a no. proportional to the revolutions made by moving system.
Train of gears drives a series of 4 or 5 pointers. There are two types of registers- pointer type and cyclometer register.

Adjustments of induction type energy meter

Some adjustments are carried out in energy meters so that they read correctly. They are,

1. Preliminary light load adjustment

Disc is so positioned that the holes are not under neath the electromagnets.
Reated voltage applied to pressure coil with no current in current coil.
Light load device adjusted until disc just fails to start.

2. Full load unity power factor adjustment

Rated voltage applied to pressure coil.
Rated full load current at upf passed through current coil.
Position of brake magnet adjusted so that disc revolves at correct speed.

induction type energy meter, adjustment of energy meter, application of energy meter

3. Lag adjustment (low power factor adjustment)

Rated voltage applied to pressure coil.
Rated full load current at .5 pf lagging passed through current coil.
Lag device adjusted so that disc revolves at correct speed.

4. Full load unity power factor adjustment and low power factor adjustment

Rated voltage applied to pressure coil.
Rated full load current at upf passed through current coil. Full load unity power factor adjustment and low power factor adjustment done so that disc revolves at correct speed.

5. Light load adjustment

Rated voltage applied to pressure coil.

Low current passed through current coil at upf.

Light load adjustment done so that disc revolves at correct speed.

Full load unity power factor and light load adjustment are gain done so that disc revolves at correct speed.

Performance is rechecked at .5 pf lagging.

Creep adjustment—pressure coils excited by 110% of rated voltage with zero load current. At this condition meter should not creep.
Hence it is the working of induction type energy meter , adjustment of induction type energy meter.

if you want to know more about the induction type energy meter you must watch this video.

Post a Comment