Voltage Regulation; Voltage Adjustment - Kohler 15/30RES Service Manual

5.7 Voltage
5.7.1

Voltage Regulation

Voltage regulation is performed by the Advanced Digital
Control (ADC) and the SCR module. The ADC monitors
generator output voltage and adjusts the excitation
current to the rotor through the SCR module.
5.7.2

Voltage Adjustment

The factory sets the voltage for correct generator
operation under a variety of load conditions. Usually, the
voltage needs no further adjustment. Adjust the voltage
when necessary according to the following procedure.
The adjustment procedure requires a meter that can
measure voltage and frequency.
Use the ADC controller to adjust the voltage, gain, and
volts/hertz (Hz). Refer to Section 4.9.2 for instructions to
adjust each parameter and save changes using
controller keypad.
Note: The ADC controller will time out and exit the
adjustment mode after approximately 1 minute if
no buttons are pressed. Any unsaved changes
are discarded if the controller times out before the
settings are saved. Refer to Section 4.9.2 for
instructions to save your settings.
Voltage Adjustment.
between 100 and 130 volts.
Gain (Stability) Adjustment. Fine tunes regulator
circuitry to reduce light flicker.
Volts/Hz Adjustment. Determines frequency (Hz) at
which generator output voltage begins to drop.
The controller maintains generator output at the
specified voltage under load until the generator engine
speed drops to a preset level (factory setting 57.5 Hz on
60 Hz models and 47.5 Hz on 50 Hz models). Then the
controller allows the generator voltage and current to
drop. The voltage/current drop enables the engine to
pick up the load. When the generator speed returns to
normal (60 Hz or 50 Hz) as load is accepted, the
generator output also returns to normal.
TP-6198 3/15
Adjusts generator output
Voltage Adjustment Procedure
WARNING
Hazardous voltage.
Can cause severe injury or death.
Operate the generator set only when
all guards and electrical enclosures
are in place.
Short circuits. Hazardous voltage/current can cause
severe injury or death. Short circuits can cause bodily injury
and/or equipment damage.
connections with tools or jewelry while making adjustments or
repairs. Remove all jewelry before servicing the equipment.
Testing live electrical circuits.
current can cause severe injury or death. Have trained and
qualified personnel take diagnostic measurements of live
circuits. Use adequately rated test equipment with electrically
insulated probes and follow the instructions of the test
equipment manufacturer when performing voltage tests.
Observe the following precautions when performing voltage
tests: (1) Remove all jewelry. (2) Stand on a dry, approved
electrically insulated mat. (3) Do not touch the enclosure or
components inside the enclosure. (4) Be prepared for the
system to operate automatically.
(600 volts and under)
1. Connect a digital voltmeter from one side of the
circuit breaker to the L0 terminal on the end bracket
casting. See Figure 5-11.
measure voltage.
Note: For 120- or 240-volt systems the voltage
measured from one side of the breaker to L0
should be approximately 120 VAC.
240-volt systems, the voltage measured
from one side of the circuit breaker to the
other should be approximately 240 VAC.
2. Start the generator set.
3. Follow the controller instructions in Section 4.9.2 to
enter the adjustment mode and increase voltage or
decrease voltage (parameter 1P) until the output
reaches the desired voltage.
Section 5 Component Testing and Adjustment
Moving parts.
Do not contact electrical
Hazardous voltage or
Set the meter to
For
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