# What arc the errors occurring in measuring devices due to stray magnetic field and temp '? Explain how to compensate them.

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What arc the errors occurring in measuring devices due to stray magnetic field and temp '? Explain how to compensate them.

1. Error due to stray magnetic fields-

Main magnetic field gets disturbed by external magnetic fields known as stray magnetic fields.

2. Compensation technique

To avoid this error, magnetic shield made up of magnetic material is placed over CC & PC.

3. Error due to Temperature

Change in room temp. changes the value of resistance of pressure coil and the stiffness of the springs.

4. Compensation technique

Using low temp. coefficient materials for coils and components this can be minimized.

Using copper and resistance alloy having a negligible resistance temp coefficient in the ratio of 1:10 for pressure coil

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