Scotchman FI-8510-20M, Manual

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PAGE 68
8.2 LIMIT SWITCH INSPECTION PROCEDURE
To determine if the limit switches are functioning properly, place the run/jog switch in the JOG position
and move the limit switches out to their farthest position.
Place the selector switch in the START position and power the machine.
Place the selector switch in the PUNCH position.
While holding the jog control, use a pencil or similar device and depress the limit switch that the
metering boss is traveling towards.
If the machine does not stop when the switch is depressed, the limit switch or the control valve is not
functioning properly.
If the machine stops when the jog control is released, the problem is in the limit switch.
For instructions if the machine does not stop when the jog control is released, SEE SECTION 8.3.
Check the limit switch plunger to make sure that it is operating freely.
The limit switch can be tested with an Ohm meter.
The limit switch wires must be disconnected from the terminal block.
The switch should read continuity with the plunger out and open with the plunger depressed.
8.3 CONTROL VALVE INSPECTION
THE MACHINE WILL ONLY TRAVEL IN ONE DIRECTION.
THIS COULD BE CAUSED BY:
1. Contamination in the hydraulic oil which causes the spool to stick in one position: With the
machine’s power off, the spool of the valve can be manually shifted. To shift the spool manually,
on each end of the control valve, there is a pin in the center of the knurled nut that holds the coil
on. Using a small punch or similar device, push these pins in by hand; first one, then the other.
After manually shifting the spool, turn the machine on and try it again. If the machine now
operates, the hydraulic oil and filter should be changed.
2. A defective coil on the control valve: The coils can be checked using an Ohm meter. The wires to
the coils must be disconnected. If the ohm reading shows open, the coil is defective and must be
replaced.