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TYPICAL VOLTAGE MEASUREMENTS
Voltage Measurement
Test Point
Meter/Range Selection
Requirement
Generator Output Voltage
Output “T” leads or bus bars,
also main circuit breaker
“line” side.
System voltage - volts AC See
generator nameplate and
connection diagram.
Regulator Output (Exciter
Stator Input)
Fl and F2 terminals at the
regulator.
200 volts D.C. range. Fl is
plus (+), F2 if minus (—
Regulator Sensing
El, E2, E3 terminals at the
Voltage the regulator.
Usually the same as the
system voltage (generator
output volts). However, in
some cases, sensing taken
from winding center taps or
instrument potential
transformers. Maximum 600
volts AC
Example:
Center tap of 480-
volt system would give 240
volts El, E2, or E3.
Example:
A 4160-volt system must use a
transformer to step
voltage
down below 600 volts.
See the connection diagram
supplied with generator set.
Regulator Input Volts
(PMG Output Volts)
“PMG” leads at the regulator
or capacitor.
200-240
VAC 300 Hz
@ 1800 rpm
180-220
VAC 250 Hz
@ 1500 rpm
CURRENT (AMP) MEASUREMENTS
Current measurement (AC) can be easily
taken with a clamp on type meter.
NOTE:
Most clamp type ammeters will not
measure D.C.
When measuring generator output current,
be sure the clamp is around all cables for
each phase. If the physical size of the
conductors or the capacity of the meters will
not permit all cables to be measured at once,
Each one can be measured individually. Add
the individual readings together to get the
total. Compare readings to the generator
nameplate (nameplate ratings are always
given per phase).