Instruction Manual

MQP20P STANDBY GENERATOR • OPERATION AND PARTS MANUAL — REV. #1 (11/28/11) — PAGE 35
MAINTENANCE
used to adjust the generator output voltage. Clockwise
adjustment increases the generator output voltage.
2. Stability Adjust — System stability is the ability of the
generator to respond to load transients. Decreasing the
stability makes the generator less sluggish and faster
to respond to load transients.
If the stability of the regulator is decreased too much,
the generator will tend to hunt under steady state
conditions. Increasing stability increases the response
time of the generator while decreasing stability
decreases response time.
The screwdriver adjustable potentiometer is used
to adjust the system stability. Clockwise adjustment
increases stability.
3. Roll-Off Frequency Selection — The roll-off point is
the frequency where the generator voltage starts to
decrease. This reduces the kilowatt load to the engine,
which allows the engine to recover in speed under any
load transient condition.
The voltage regulator has the roll-off point preset to
58 Hz in the 60 Hz mode. To change the roll off point,
perform the following:
a. Adjust the engine to the desired rated speed
(60 Hz).
b. Set the voltage to the desired setting at rated
speed.
c. Adjust the engine speed to the desired roll-off point.
d. Turn the potentiometer counterclockwise until the
voltage returns to rated.
e. Readjust the engine speed to rated speed.
Adjustment Procedure
1. Make sure that the voltage regulator is connected
correctly to the generator. Refer to the generator wiring
diagram.
2. Tur n the Voltage Adjust potentiometer fully
counterclockwise.
3. Turn Stability Adjust potentiometer fully clockwise.
4. Set the remote Voltage Adjust to the center position.
5. Connect the positive lead of a 100 VDC voltmeter to
F1 and the negative lead to F2 or use an appropriate
AC voltmeter on the generator output leads.
6. Start and run the generator at no load and rated speed.
The generator voltage should build up to a minimum
level. If it does not build up, refer to the generator
manual for field flashing information.
7. Slowly adjust the Voltage Adjust potentiometer until
the generator voltage reaches the nominal value. Also
adjust the remote Voltage adjust to set the generator
voltage to the exact value desired.
8. Turn the Stability Adjust potentiometer counterclockwise
until instability is shown on the voltmeter. With the
system operating in an unstable condition, slowly
adjust the Stability Adjust potentiometer clockwise until
generator stability is reached.
9. Interrupt the regulator power for a short period of time
(1 to 2 seconds).
10. If the generator remains stable, no further adjustment
is necessary.
11. If generator does not remain stable, increase the
stability slightly and interrupt the regular power again.
12. Repeat step 11 until system stability is reached and
maintained.
GENERATOR STORAGE
For long term storage of the generator the following is
recommended:
1. Drain the fuel tank completely. Treat with a fuel stabilizer
if necessary.
2. Completely drain the oil from the crankcase and refill,
if necessary, with fresh oil.
3. Clean the entire generator, inside and outside.
4. Disconnect the battery.
5. Make sure engine coolant is at proper level.
6. Cover the generator and store in a clean, and dry place.