12 Generac
®
Power Systems, Inc.
2.11.2 TRANSFER SWITCH
If this generator is used to supply power to any elec-
trical system normally powered by an electric utility,
the National Electrical Code requires that a transfer
switch be installed. The transfer switch prevents elec-
trical backfeed between two different electrical sys-
tems. (For additional information, see the applicable
transfer switch manual for this unit.) The transfer
switch, as well as the generator and other standby
components, must be properly located and mounted
in strict compliance with applicable codes, standards
and regulations.
2.11.3 FUEL SYSTEM
Make sure the fuel supply system to the generator (a)
delivers the correct fuel at the correct pressure and
(b) is properly purged and leak tested according to
code. No fuel leakage is permitted. See
“Specifications” (Section 1.10) for more information.
2.11.4 GENERATOR SET LUBRICATION
Check the engine crankcase oil level before operating
and add oil to the proper level – the dipstick “FULL”
mark. Never operate the engine with the oil level
below the dipstick “ADD” mark. See “Specifications”
(Section 1.10) and “Engine Oil Recommendations”
(Section 1.14).
NOTE:
This engine is shipped from the manufacturer
with 15W-40 oil. This oil should be changed after
30 hours of operation.
2.11.5 ENGINE COOLANT
Have the engine cooling system properly filled with
the recommended coolant mixture. Check the system
for leaks and other problems. See “Specifications”
(Section 1.10) and “Coolant” (Section 1.15).
2.11.6 BELT TENSION
Check the engine fan belt tension and condition prior
to placing the unit into service and at recommended
intervals. Belt tension is correct when a force of
approximately 22 pounds (10 kg), applied midway
between pulleys, deflects the belt about 3/8- to 5/8-
inch (10 to 16 mm).
2.11.7 ELECTRICAL SYSTEM
Make sure the generator is properly connected to an
approved earth ground and/or ground rod.
Make sure the generator battery is fully charged, prop-
erly installed and interconnected, and ready for use.
Check to ensure that there are no loose electrical con-
nections. Restrain any loose wires to keep them clear
of any moving generator set components.
3.1 USING A STANDARD “GTS”
TRANSFER SWITCH
When required, the pre-packaged standby generator
can be installed with a standard Generac “GTS” type
engineered automatic transfer switch.
When a GTS type transfer switch is used, it controls
automatic operation and automatic transfer as fol-
lows:
• Solid state circuits in the transfer switch monitor
utility power source voltage.
• When utility source voltage drops below a pre-set
level, transfer switch action closes the circuit. The
engine then cranks and starts as controlled by the
pre-packaged generator’s Control Module circuit
board.
• After the engine starts and when the generator AC
output voltage and frequency have reached a
pre-set value, transfer switch circuits signal the
transfer switch main contacts to actuate to the
“STANDBY” power source side. Generator AC out-
put then powers load circuits.
• When the utility power source voltage is restored
above a pre-set level, transfer switch solid state
circuits signal the switch main contacts to move
back to their utility power source side.
• Following re-transfer back to the utility power
source side, transfer switch circuit board action
opens the circuit. Engine then shuts down.
NOTE:
If the generator is installed in conjunction with a
standard GTS type transfer switch, refer to the
applicable transfer switch manual for exact oper-
ating parameters and timing sequences.
3.2 CONTROL CONSOLE
COMPONENTS
The components of a liquid-cooled generator control
console (Figure 3.1) are as follows:
Figure 3.1 - Liquid-Cooled Generator Panel
AUTO
MANUAL
OFF
FUSE
15-A
AGC
FAULT
INDICATOR
SET
EXERCISE
TIME
ON
HOUR METER
Section 3 — Operation
Guardian Liquid-cooled 15 kW, 20 kW and 25 kW Generators