Norton Abrasives C6120, C3120, C3126 J. Solenoid Coils, K. Electrical Polarity, Repair Procedure

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

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