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5
Troubleshooting
CAUTION
There are no user serviceable parts inside the Model 3502 Optical
Chopper Controller or Motor Head. Work performed by persons not
authorized by New Focus will void the warranty.
5.1
Normal Startup Operation
When the Chopper Controller is properly connected to the power mains and a
Chopper Head, and is turned on, the front panel LEDs will blink and the display
will show
PASS
before recalling the last Chopper Controller set up. The motor
should begin turning and come to speed within about one minute.
5.2
Symptoms and Steps to Follow
If nothing happens:
Check that the power cord is connected to the Chopper Controller.
Check that the Chopper Head is connected to the Chopper Controller. Do not
connect the Chopper Head when the Chopper Control unit is powered on.
Fails test at start up:
Please contact New Focus for service.
Motor fails to turn:
With power removed from the control unit, check that the wheel is free to turn
without obstructions. Also, this condition may be caused by a broken shielded
Ethernet cable between the Chopper Controller and the Chopper Head.
Substitution of a known functional shielded Ethernet cable is the best solution.
Motor spins down and stops when sync frequency is changed:
The Chopper Controller will stop driving the motor in the Chopper Head if an
externally-supplied sync frequency is outside the range of the chopping
frequencies allowed for a given wheel setting. Verify that this external signal is
of the correct frequency.
