Generac Power Systems Liquid-cooled Standby Generators 004090-2 - Manual (Page 7)

Generac ® Power Systems, Inc. 5
Figure 3 represents a single-phase, 3-wire generator AC
connection system. The stator assembly in this system
consists of a pair of stationary windings, with two leads
brought out of each winding. Each single winding can
supply 120 volts AC, 60 Hertz. When the two windings
are connected in series, a 240 volts, 60 Hertz AC output
results. Typically the two “hot” leads in the circuit are
Wires No. 11 and 44. The “Neutral” leads are the junc-
tion of Wires 22 and 33.
Figure 3 - Generator AC Connection System
MAIN CIRCUIT BREAKER
The generator’s main circuit breaker is included with the unit as
shipped from the factory. The breaker for each unit is described as
follows:
GENERATOR FUEL SYSTEM
Your unit has been factory tested and adjusted using a
natural gas fuel system. If propane (LP) gas is pre-
ferred, contact an authorized service dealer.
WARNING: Gaseous fuels such as natural and LP
(propane) gas are highly explosive. Even the slightest
spark can ignite such fuels and cause an explosion. No
leakage of fuel is permitted. Natural gas, which is lighter
than air, tends to collect in high areas. LP gas is heavier
than air and tends to settle in low areas.
ENGINE PROTECTIVE DEVICES
The engine has several safety switches which cause the
engine to automatically shut down under the following
conditions: low oil pressure, high coolant temperature,
engine overspeed, low coolant level or overcrank.
LOW OIL PRESSURE SWITCH:
This switch is normally-closed (N.C.) but is held open
by engine oil pressure during engine running. Should
operating oil pressure drop below about 8-10 psi (55-68
kPa), the switch contacts close and the engine shuts
down automatically (Figure 4).
Figure 4 - Low Oil Pressure Switch
HIGH COOLANT TEMPERATURE SWITCH:
Normally open (N.O.) thermostatic switch has sensing
tip which is immersed in captive coolant. Should
coolant temperature exceed about 230°F (110°C), the
switch contacts close, which causes the engine to shut
down automatically (Figure 5).
Figure 5 - High Coolant Temperature Switch
Section 1 - General Information
Guardian Liquid-cooled 10 kW, 15 kW, 20 kW and 25 kW Generators
MODEL CIRCUIT BREAKER RATING
004090-2, 004124-1 50 amp BQ2 breaker
004091-2, 004125-1 40 amp BQ3 breaker
004092-2, 004128-1 90 amp BQ2 breaker
004093-2 70 amp BQ3 breaker
004094-2, 004126-1 70 amp BQ2 breaker
004095-2, 004127-1 60 amp BQ3 breaker
004096-2, 004130-1 125 amp BQ2 breaker
004097-2, 004131-1 90 amp BQ3 breaker
004474-0, 004475-0 125 amp BQ2 breaker