Kohler 27EFOZ, Service Manual

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TP-5936 7/04 30 Section 7 Generator Troubleshooting
7.5 Voltage Regulator Adjustment
The voltage regulator is factory set and, under normal
circumstances,
requires no further adjustment.
However, if the voltage regulator has been replaced, or
tampered with, or if voltage/frequency reconnection has
been done, readjust the voltage regulator according to
the following procedure.
The voltage regulator
components are identified and described in the
following paragraphs.
66 55
4 3
AC
F +
8
7
6
5
4
3
2
1
Input
Green
Output
Red
V/HZ
Stab
Sensing
Yellow
B1 B2
2 1
F --
AC
AC
Volts
1
2
4 5
6
7
3
TP-593656
1. Sensing leads
2. Main field (rotor)
3. Stator windings
4. Rectifier
5. Armature
6. Exciter field
7. Voltage regulator power supply leads
Figure 7-4 PowerBoost
t
V Voltage Regulator
Connection
TP-593657
8
7
6
5
4
3
2
1
Input
Green
Output
Red
STAB
Sensing
Yellow
V/HZ VOLTS
1
2
3 4 5
6
1. LED1 (green input)
2. LED2 (red output)
3. Voltage potentiometer 4. LED3 (yellow sensing)
5. Volts/Hz potentiometer
6. Stability potentiometer
Figure 7-5 PowerBoost
t
V Voltage Regulator
Note: The voltage regulator is located inside the
generator set controller.
Voltage Adjustment Pot. Pot adjusts the generator
output.
Stability Pot. Pot fine tunes the regulator circuitry to
reduce light flicker.
Volts/Hz Pot. Pot adjustment determines the engine
speed (Hz) at which the generator output begins to drop.
Voltage Regulator Adjustment Procedure
1. Place the generator set controller start/stop switch
in the STOP position.
2. Turn the Volts/Hz and the stability pots fully
counterclockwise. Connect the voltmeter to the AC
circuit or an electrical outlet.
3. Start the generator set and rotate the voltage
adjustment pot clockwise (increase voltage) or
counterclockwise (decrease voltage) until the
desired output voltage is achieved.
4. Rotate the stability pot clockwise until light flickers
minimally.
5. Readjust the voltage adjustment pot until the
desired output voltage is achieved.
6. Adjust the engine speed to the specified cut-in
frequency as measured on the frequency meter.
The factory setting is 57.5--58 Hz for 60 Hz models
and 47.5--48 Hz for 50 Hz models.
7. Rotate the volts/Hz pot clockwise until the voltage
level as measured on the voltmeter begins to drop.
When the regulator is set to these specifications,
the generator will attempt to maintain normal
output until the engine speed drops below the
frequency set in step 6 as load is applied.
8. Readjust the engine speed to 1800 rpm for 60 Hz
models and 1500 rpm for 50 Hz models.
9. Readjust the voltage adjustment pot until the
desired output is achieved.
10. Readjust the stability pot until light flickers
minimally.
11. Place the generator set controller start/stop switch
in the STOP position.