Generac
®
Power Systems, Inc.
15
Section 3 - Operation
Guardian Liquid-cooled 25 kW Generator
3. Under no load condition, increase the GAIN pot
as much as possible without causing instability.
4. Apply 1/4, 1/2, 3/4 and full load to the unit.
Decrease the GAIN pot if there is instability at any
load point.
5. Under full load condition, increase the stability
pot until the unit returns to 60 Hertz (or 50 Hertz
in 50 Hertz applications).
6. Reduce load to 3/4, 1/2, 1/4 and no load.
Decrease the stability pot if there is instability at
any load point.
7. Adjust differential pot to make the recovery to
load changes even faster and minimize load
change undershoot and overshoot. If it is set too
high, it may introduce oscillations at some load.
It can be set to zero (full CCW) if a small amount
causes oscillations at some load.
Figure 3.2 — Engine Governor Adjustment
3.5
RETRANSFER AND SHUTDOWN
When utility power source voltage has been restored,
electrical loads may be transferred back to that
source and the generator can be shut down as fol-
lows:
• Verify that utility power supply voltage to the trans-
fer switch has been positively turned Off, using
whatever means provided (such as utility main line
circuit breaker).
• Set the generator’s main circuit breaker to its Off
or Open position.
• Let the generator engine run at no-load for a few
minutes, to stabilize internal unit temperatures.
• On the generator console, set the Auto/Off/ Manual
switch to Off. Wait for engine to come to a complete
stop.
• For transfer to utility position, refer to the Owner’s
Manual of the particular transfer switch.
• Turn on the utility power supply to the transfer
switch, using whatever means provided (such as a
utility main line circuit breaker). The utility power
source now powers the loads.
3.6
AUTOMATIC OPERATION
To set the system for fully automatic operation, pro-
ceed as follows:
• Check that load circuits are connected to the
utility power supply.
• Set the AUTO/OFF/MANUAL switch to its AUTO
position.
• Set the generator main circuit breaker to its ON or
CLOSED position.
3.7
WEEKLY EXERCISE CYCLE
The engine control board will start and run the gen-
erator once every seven days for approximately 12
minutes. If utility should fail during this exercise
period, the engine control board will transfer the load
to the generator output and continue to run until util-
ity returns.
On the day, and at the time of day chosen for the gen-
erator to exercise, set the weekly exercise cycle as fol-
lows:
1. Place the AUTO/OFF/MANUAL switch in the auto
position (Figure 3.3).
2. Press and hold the “Set Exercise” switch for five
seconds, then release.
Figure 3.3 - “Set Exercise Time” Switch
FOR STAND-BY SERV
TRANSFER SWITCH IN
ATTENTION: POUR L'
ICE A UN COM
CAN
RISK OF ELECTRICAL
PARTS INSIDE. R
THIS EMERGEN
N AUTOMATICA
INJURY REMO
LOW COOLANT LEVEL
HI COOLANT TEMPERATURE
FLASHING GREEN LED = NO UTILITY SENSE
5 FLASHING RED LED'S = EXERCISER NOT SET
(IN AUTO MODE ONLY) SOLID GREEN LED = SYSTEM READY, UTILITY POWER ON
(SEE OWNER'S MANUAL FOR COMPLETE DETAILS)
LED INDICATORS:
RED LED'S = INDIVIDUAL FAULT
OVER CRANK
SYSTEM READY
LOW BATTERY
LOW OIL PRESSURE
OVER SPEED
OFF
MANUAL
AUTO
START, RUN THROUGH THE EXERCISE
CYCLE AND SHUTDOWN.
TIME
SET
EXERCISE
TO AUTO POSITION.
SWITCH IN "ON" POSITION FOR
1) PLACE AUTO/OFF/MANUAL SWITCH
2) HOLD "SET EXERCISE TIME"
TO SET EXERCISER TIME
10 SECONDS. THEN THE UNIT WILL
THE EXERCISER IS NOW SET. ALL
FIVE RED LED'S WILL FLASH FOR
THREE SECONDS AND RELEASE.
ON
0F0653
OFF
