Page 7 - August 2022 Track N Times

TECHNICAL TRAINING

Reverse Power Continued

regulator output is at 63 volts (Max voltage) it cannot ex-
cite the generator anymore and goes into reverse power.
To determine if the generator has 1 or multiple bad diodes
is to measure the F+ (red probe) to F- (black probe) volts
DC on the back of the regulator (NOTE: Ensure the
probes do not come in contact with each other.)
with the engine running unloaded or online (small load). If
the diodes are bad, it will need more field excitation, 20 or
more volts, if everything is good it will be more like 10
volts. The only difficulties is that the generator field wires
need to remain connected to the back of the regulator. To
take the measurements the wires need to be pulled off just
enough to get the probes on the terminal (spade connect-
ors). The values listed are typical for a 1300KW generator- if
abnormal readings are measured each diode will need to be
measured one at a time on the rectifier.

Page 5 AUGUST 2022