Norton Abrasives C6136 - Manual (Page 50)

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the ground wire du e to the construction of the motor solenoid
switch (See Electrical Switches). Likely spots for "faults" are
the same as shorts see above.
J. Solenoid Coils
Coils are used in solenoid start switches. Failures can be
caused by vibration, water, improper voltage or corrosion.
The best way to test a coil is with an OHM meter. The meter
should read some value of OHMS and an infinite reading
means that the coil has an open circuit. The reading between
any lead on the coil and the "can" should be infinite unless
there is only one lead wire and the coil is grounded to the
can.
K. Electrical Polarity
Motors and valves supplied by Monarch can be used on
either positive or negative ground systems with the exception
of the model M 310 or any system using the round (cylindrical
shaped) manual valve with a covered switch on the back
plate. In these units, there is a capacitor connected on the
switch which must be "polarized." They are normally sent out
for negative ground systems and if used on a positive ground
system, the capacitor must be turned end for end as the +
sign must face the most positive side of the circuit. Failure to
align properly will cause the lead wire to "blow" off the
capacitor, which in turn could make a "Ground Fault' and
cause the motor to run with no control.
12. Diagnosing and Repairing Hydraulic Pump Relief Valves
NOTE: When testing or making adjustments on the relief valve, the system
must be "dead headed"(cylinder at full stroke or in a position where cylinder
movement is zero).
A. Relief valve pressure too high.
1. Symptoms:
•
Amp draw and battery drain excessive when system is
"dead headed."
• Motor RPM is slow in comparison to full load system
operation.
2. Repair Procedure:
Turn relief valve adjusting screw counterclockwise using a
gauge, tee'd into the high pressure line to record the proper
pressure setting.
Note: On the "internal" relief valve the flush 1/4" pipe plug
will have to be removed to reach the adjusting screw (see