Westerbeke 20.0KW sbeg Operator's Manual page 44

VOLTAGE REGULATOR ADJUSTMENTS
Description
The voltage regulator is an advanced design which ensures
optimum AC alternator performance.
It
is equipped with
complete protection circuitry to guard against operating
conditions that could be detrimental to the AC alternator.
Volts
FUSE
PROTECTS THE REGULATOR BOARD
FROM AN ELECTRICAL OVERLOAD
This potentiometer is used to adjust output voltage. At proper
engine operating speed the output voltage should be held at
±I
%
from a no-load condition to a full rated generator output
and from power factor 1.0 - 0.8 with engine drive speed
variations up to -6%. Prior to starting the engine, tum the
VOLT and STAB trimmers (using a mini phillips screw-
driver) fully in a counter clockwise (Minimum) direction
until you feel them hit their stops. Tum the AMP and HER1Z
trimmers completely clockwise (Maximum) in the same
manner. With the generator running at no-load, at normal
speed, and with VOLT adjust at minimum, it is possible that
output voltage will oscillate. Slowly rotate the VOLT
adjust clockwise. The voltage output of the alternator will
increase and stabilize. Increase the voltage to the desired
value. In this situation, only the green LED will stay lit.
red
~
green
c
~
~
yel/ow
~
Hertz
Amp
E
Slab
g
'E
Vall
""
g
~
VOLTAGE REGULATOR DIAGRAM
Stability
This potentiometer pennits variation of the regulator's
response to generator load changes so as to limit
overcompensation and obtain a minimum recovery time to
the normal voltage output.
In order to adjust the regulator stability the alternator must be
running at no-load and the output must be monitored.
Tum the STAB adjust slowly clockwise until the voltage
starts to fluctuate. At this point rotate the STAB adjust
counterclockwise until the voltage is stable within I or 2
tenths of a volt.
Amp-Hertz
These two adjustments are used in conjunction with the two
protection circuits in the voltage regulator that are indicated
by the illumination of a colored LED lights.
1.
Delayed overload protection (yellow LED).
2. Low speed protection (red LED).
Both systems have an intervention threshold which can be
adjusted using the respective potentiometer. Each of the two
circuits are able to cause an adequate reduction in excitor
voltage to safeguard the excitor windings and prevent their
overheating.
The overload protection system has a delay which permits
temporary overloading of the generator during times such as
motor start-up or other similar load surge demands. The
regulator also has a third LED (green), that glows during
generator operation to indicate correct operation of the
regulator with the generator.
Engines & Generators
32