JS SERIES PUMPS
MR−03955
FM
APPROVED
TROUBLESHOOTING
PAGE B − 4
Insulation Resistance
Set the megohmmeter at R x 100, and zero-ba-
lance it. Test as follows:
a. Shut off incoming power to the control box,
and disconnect the motor power cable leads.
Connect one megohmmeter test lead to the
motor cable green/yellow ground lead. Touch
the other test lead to each of the motor cable
leads in turn. Note the readings.
b. Readings will indicate resistance values in
both the power cable and motor windings.If
resistance reads infinity (
1
), insulation is
good. If resistance reads between infinity (
1
),
and 1 megohm, insulation is acceptable but
should be rechecked regularly. If resistance
reads less than 1 megohm, insulation should
be checked more closely and frequently.
c. If readings indicate that a ground exists, the
motor must be returned to the factory or to a
Gorman-Rupp authorized repair facility.
