Franklin 2007 Manuel D’Utilisation

The values below are for copper conductors. If aluminum 
conductor drop cable is used, the resistance will be 
higher. To determine the actual resistance of the 
aluminum drop cable, divide the ohm readings from this 
chart by 0.61. This chart shows total resistance of cable 
from control to motor and back. 

The winding resistance measured at the motor should 
fall within the values in tables 13, 22, 24 & 26. When 
measured through the drop cable, the resistance of 
the drop cable must be subtracted from the Ohmmeter 
readings to get the winding resistance of the motor. See 
table below.

Insulation resistance varies very little with rating. Motors of all hp, voltage, and phase rating have similar values of 
insulation resistance.

The table above is based on readings taken with a megohm meter with a 500 VDC output. Readings may vary using a lower 
voltage Ohmmeter, consult Franklin Electric if readings are in question.

 A new motor (without drop cable).

 A used motor which can be reinstalled in well.

200,000,000 (or more)

10,000,000 (or more) 

200.0 (or more)

10.0 (or more)

2,000,000 (or more) 

500,000 - 2,000,000

Less than 500,000

2.0 (or more)

0.50 - 2.0

Less than .50

New motor.

Motor in good condition.

Insulation damage, locate and repair.

0.544

0.338

0.214

0.135

0.082

0.052

0.041

0.032

0.026

0.021

0.017

0.013

0.010

0.0088

0.0073

0.0063

0.0056

0.0044

0.0037

0.0032

45