The insulation resistance of a DC motor is observed to be 15 MΩ at a temp. of 70°C. what is its value corrected to 40°C. the correction factor for 70°C is 8.0.

The insulation resistance of a DC motor is observed to be 15 MΩ at a temp. of 70°C. what is its value corrected to 40°C. the correction factor for 70°C is 8.0. 
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1 Answer

Answer :

Observed resistance at 70°C – 15 MΩ.

Temperature correction factor – 8.

Rm = kt * Rt           kt – correction factor.

Rm = 8 * 15          Rt – resistance measured at +°C.

Rm = 120 MΩ.       Rm – corrected value to 40°C

The IR of DC motor corrected to 40°C is 120 MΩ. 
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