Terex Genie AL5HT, Service Manual

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May 2015 Service Manual
Light Ballast
Part No. 1265482 AL5HT 61
9-2
Light Ballast
High voltage. Exposure to
electrical wires or electrical
current will result in death or
serious injury. Turn off all power
when not needed for testing. Use
extreme caution when working
with high voltage electrical
components.
Electrocution/burn hazard.
Attempting to service the
machine before the capacitor is
fully discharged will result in
death or serious injury.
Note: Be sure the engine has been turned off for at
least 15 minutes before servicing the machine. Use
a voltmeter to confirm there is no residual voltage
in the capacitor.
Note: This procedure is only for the capacitors
which are attached to the lighting ballasts. To test a
generator capacitor, see 5-2, How to Check a
Generator Capacitor.
1 Open both cabinet doors and locate the light
ballast boxes on each side of the machine.
2 Choose a ballast box. Tag and disconnect the
wire harness connector from the ballast box.
Note: If the ballast capacitor to be tested is located
under another ballast box, the top ballast box will
need to be removed first.
3 Remove the ballast box cover fasteners.
4 Using an insulated conductor or a screwdriver
with an insulated handle, discharge the
capacitor by shorting across the capacitor
terminals.
Note: Refer to the instructions which are provided
for your multimeter to ensure the diode is
accurately tested.
High voltage. Exposure to
electrical wires or electrical
current will result in death or
serious injury. Turn off all power
when not needed for testing. Use
extreme caution when working
with high voltage electrical
components.
5 With an ohmmeter set to its highest resistance
scale, connect the ohmmeter leads to the
capacitor terminals and observe the reading
on the meter. Then, reverse the connections
and observe the reading on the meter.
Result: The meter indicates a resistance
which then gradually decreases. The capacitor
is working.
Result: The meter indicates a very high
resistance which does not decrease. The
capacitor is faulty and should be replaced.
Result: The meter indicates a very low
resistance which does not increase. The
capacitor is faulty and should be replaced.
Probable causes of capacitor failure:
•
Normal end-of-life failure.
•
Overheated due to light fixture heat or high
ambient temperature.
•
Incorrect capacitor voltage rating.
•
Capacitor becomes loose in ballast box.