Curtis 1204 Manual page 34

Curtis PMC 1204/1205 Manual
1 Check for power to the controller
TEST
Leave the keyswitch off for these tests.
1-A
Verify that battery (-) connects to the B- terminal of the controller.
1-B
Connect voltmeter (-) lead to this point.
Connect voltmeter (+) to the battery side of the main contactor.
1-C
Check for full battery voltage. If it is not there, the trouble is in the
battery pack, the cables to it, or the power fuse.
Connect the voltmeter (+) lead to the controller B+ terminal. You
1-D
should read a voltage 1 to 5 volts less than the full battery voltage. If
this voltage is zero or close to zero, the trouble is either a bad
controller, a bad 250 Ω resistor across the contactor, or an incorrectly
connected cable between the contactor and the controller. Trace the
cable to make sure it is hooked up right. Remove and test the 250 Ω
resistor with an ohmmeter. If these check out, the controller is
malfunctioning. If you see full battery voltage at this point, then the
contactor has welded and must be replaced.
2 Check for main contactor operation and KSI
TEST
Turn the key on, place the forward/reverse switch in forward or
2-A
reverse, and depress the footpedal until its microswitch operates. (In
these procedures, we assume the footpedal is equipped with the
recommended microswitch.)
This should cause the main contactor to operate with an audible
2-B
click. Connect the voltmeter across the contactor coil terminals. You
should see full battery voltage (minus the polarity diode drop).
The controller KSI terminal should also be getting full battery
2-C
voltage. Verify this by connecting the voltmeter (-) to the controller's
B- terminal, and the voltmeter (+) to the controller's KSI terminal.
If the contactor and KSI terminal are not getting voltage, that's the
2-D
problem. Use the voltmeter to find out where it is not getting
through. Connect the voltmeter (-) to the controller's B- terminal
and check the following points with the voltmeter (+) lead to trace
TROUBLESHOOTING & BENCH TESTING
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