Generac
®
Power Systems, Inc. 15
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.
2. Press and hold the “Set Exercise” switch for three
seconds, then release.
At this time all five red LEDs will flash for approxi-
mately 10 seconds, then the engine will start and run
for it’s 12 minute exercise period, then shut down.
The generator will now start and run each week at the
same time.
If DC power to the control board is lost, the weekly
exercise setting will be lost. This is indicated by all
five red LEDs continually flashing. In this state the
generator will still start and run in manual mode, or
automatically start and run if UTILITY is lost while in
AUTO mode, but it will not perform a weekly exercise
cycle.
If a failure occurs while running in this mode, the five
red LEDs will stop flashing, the individual fault LED
will turn on and the engine will shut down. Once the
AUTO/OFF/MANUAL switch has been switch to OFF,
the individual fault LED will turn OFF and the five
red LEDs will begin flashing to show exercise has still
not been set.
Figure 3.2 - “Set Exercise Time” Switch
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MAIN
Section 3 - Operation
Guardian 40kW Liquid-cooled Generators