16 Generac
®
Power Systems, Inc.
3.5.2 TRANSFER BACK TO UTILITY POWER
SOURCE
When utility power has been restored, transfer back
to that source and shut down the generator. This can
be accomplished as follows:
1. Set the generator’s main circuit breaker to its
OFF (or open) position.
2. Let the engine run for a minute or two at no-load
to stabilize the internal temperatures.
3. Set the generator’s AUTO/OFF/MANUAL switch to
its OFF (or open) position. The engine should
shut down.
4. Check that utility power supply to the transfer
switch is turned OFF.
Do not attempt to activate the transfer switch
manually until all power voltage supplies
to the switch have been positively turned off.
Failure to turn off all power voltage supplies
may result in extremely hazardous and possibly
fatal electrical shock.
5. Use the manual transfer handle inside the trans-
fer switch to move the main contacts back to their
UTILITY position, i.e., loads connected to the util-
ity power source (Figure 3.2).
6. Turn ON the utility power supply to the transfer
switch using the means provided.
7. Set the system to automatic operation as outlined
in “Automatic Transfer Operation,” Section 3.3.
3.6 SETTING THE EXERCISE TIMER
This generator is equipped with an exercise timer.
Once it is set, the generator will start and exercise
once every seven days, on the day of the week and at
the time of day the following sequence is completed.
During this exercise period, the unit runs for approx-
imately 12 minutes and then shuts down. Transfer of
loads to the generator output does not occur during
the exercise cycle.
A switch on the control panel (see Figure 3.1) permits
selection of the day and time for the system to exer-
cise. At the chosen time, perform the following
sequence to select the desired day and time of day the
system will exercise.
1. Verify that the AUTO/OFF/MANUAL switch is set
to AUTO.
2. Hold down the “Set Exercise Time” switch until
the generator starts (approximately 10 seconds)
and then release.
3. The generator will start and run for approximate-
ly 12 minutes and then shut down on its own.
The exerciser will then be set to run at that time
of day every week.
NOTE:
The exerciser will only work in the AUTO mode
and will not work unless this procedure
is performed. The exerciser will need to be reset
every time the 12-volt battery is disconnected and
then reconnected. The exerciser WILL NOT work
if dip switch 2 on the controller printed circuit
board (Remote Not Auto) is ON.
3.7 PROTECTION SYSTEMS
3.7.1 LOW OIL PRESSURE SWITCH
This switch (Figure 3.3) has normally closed contacts
that are held open by engine oil pressure during
cranking and operating. Should oil pressure drop
below the 8 psi range, switch contacts close, and the
engine shuts down. The unit should not be restarted
until oil is added. The AUTO/OFF/MANUAL switch
must then be turned to OFF and then back to AUTO.
3.7.2 HIGH TEMPERATURE SWITCH
This switch’s contacts (Figure 3.3) close if the tem-
perature should exceed approximately 140º C (284º
F), initiating an engine shutdown. The generator will
automatically restart and the LED on the generator
control panel will reset once the temperature has
returned to a safe operating level.
Figure 3.3 – Low Oil Pressure and
High Temperature Switches
3.7.3 OVERCRANK
This feature prevents the generator from damaging
itself when it continually attempts to start and anoth-
er problem, such as no fuel supply, prevents it from
starting. The unit will crank and rest for a preset time
limit. Then, it will stop cranking, and the LED on the
generator control panel will light indicating an over-
crank failure. The AUTO/OFF/MANUAL switch will
need to be set to OFF and then back to AUTO to reset
the generator control board.
Oil Filter
Oil
Drain
Hose
Low Oil Switch
High Temp Switch
L
o
o
s
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DANGER
Section 3 — Operation
Guardian Air-cooled 7 kW, 12 kW and 15 kW Generators