TLD GPU-406, Manual

Page: 37 / 74

Creation: 01.31 - 2014 2-4-9
GPU - 406
GPU - 409
Generator and Controls (cont.)
PROBLEM CAUSE REMEDY
4. Poor regulation, or erratic
voltage output
A. The engine is not a rated
speed, or the engine speed is not
stable. A. Ensure that the J1939 bus
connections are in good condition.
Consult chapter 5 for engine
performance troubleshooting.
Contact the engine manufacturer
or TLD if necessary.
B. Circuit components inside the
GCM are defective. B. Replace the GCM.
C. The engine is overloaded. C. Reduce the load at the aircraft
to the rating of the TLD generator.
Overloading can also occur for a
short period when the aircraft first
requests power.
D. The engine is not producing full
power. D. Refer to chapter 5 to
troubleshoot engine performance
issues. Contact the engine
manufacturer or TLD if necessary.
E. The engine charging voltage is
less than 24VDC. E. Refer to chapter 5 to
troubleshoot engine charging
system issues. Contact the engine
manufacturer or TLD if necessary.
F. Fault in the generator exciter F. Refer to the generator manual.
The exciter may require
replacement.
5. Voltage recovery is slow (takes
more than 3 seconds) when the
load changes.
A. Faulty engine computer or
other performance issue. A. Refer to chapter 5 to
troubleshoot engine performance
problems.
B. Low fuel pressure B. Check the fuel supply lines and
fuel filter. Repair or replace if it is
necessary.
C. Circuit components inside the
GCM are defective. C. Replace the GCM.
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