TLD GPU-406 - Page 36

Creation: 01.31 - 2014 2-4-8
GPU - 406
GPU - 409
Generator and Controls (cont.)
PROBLEM
CAUSE
REMEDY
2. Voltage is high or unbalanced,
as shown on the screen, and it
cannot be adjusted.
A. No voltage sensing connection
to one or more of the generator
phases
A. Correct the wiring.
B. Faulty GCM
B. Replace the GCM
3. Voltage is high or unbalanced,
and it can be adjusted.
A. Poor connections to the voltage
sensing terminals from the
contactor to the GCM.
A. Correct the wiring to the
regulator.
B. Poor connections to the neutral
sensing terminals from the
distribution block to the GCM.
B. Correct the wiring to the
regulator.
C. Voltage display is inaccurate
C. Correct the wiring to the
regulator. The GCM may require
calibration. Refer to the TLD
document 102-00688.
D. The voltage adjustment on the
GCM is incorrect.
D. Calibrate the GCM.
E. Circuit components inside the
GCM are defective.
E. Replace the GCM.
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