The type of damping use for moving iron instruments is ______.

M.C. Instruments

M.I. Instruments

1. MC type instruments are more accurate.

1. MI type are less accurate than MC type.

2. Manufacturing cost is high.

2. Cheap in cost.

3. Reading scale is uniformly distributed.

3. Non-uniform scale

(scale cramped at beginning and finishing)

4. Very sensitive in construction & for input.

4, Robust in construction.

5. Low power consumption

5. Slightly high-power consumption.

6. Eddy current damping is used.

6. Air friction damping is used.

7. Can be used only for D.C measurements.

7. Can be used for A.C as well as for D.C measurements.

8. Controlling torque is provided by spring.

8. Controlling torque is provided by gravity or spring

9. Deflection is proportional to current. (θ α l).

9. Deflection is proportional to the square of the current.

(θ α l2).

10. Errors are set due to the ageing of control

springs. Permanent magnet (i.e. No Hysteresis loss).

10. Errors are set due to hysteresis and stray fields.

(i.e. hysteresis loss takes place).