Generac Power Systems 005040-0 - Manual (Page 6)

4 Generac ® Power Systems, Inc.
1.1 GENERATOR
This equipment is a liquid-cooled, engine-driven gen-
erator set. The generator is designed to supply elec-
trical power that operates critical electrical loads
during utility power failure. The unit has been facto-
ry-installed in a weather resistant, all metal enclosure
and is intended for outdoor installation only. Use this
generator as a source of electrical power for the oper-
ation of 120 and/or 240VAC, single-phase loads.
These models are available. They are rated as fol-
lows:
Model 005040-0: Provides 25,000 watts (25 kW) of single-phase
power.
Model 005053-0: Provides 20,000 watts (20 kW) of single-phase
power.
Model 005054-0: Provides 15,000 watts (15 kW) of single-phase
power.
If this generator is used to power electrical
load circuits normally powered by a utility
power source, it is required by code to install
a transfer switch. The transfer switch must
effectively isolate the electric system from the
utility distribution system when the generator
is operating (NEC 701). Failure to isolate an
electrical system by such means results in
damage to the generator and may also result
in injury or even death to utility power work-
ers due to backfeed of electrical energy.
1.2 TRANSFER SWITCH
This generator system is intended to be used with a
matched automatic transfer. It may be supplied in
either a NEMA 1 enclosure or a NEMA 3R enclosure.
The NEMA 1 enclosure is intended for indoor use
only. The NEMA 3R enclosure is weather proof and
can be used indoors or outdoors. Follow these rules:
• Install the transfer switch on a firm, sturdy sup-
porting structure.
• To prevent switch distortion, level the switch if nec-
essary. This can be done by placing washers
between the switch enclosure and the mounting
surface.
• Never install the switch where water or any corro-
sive substance might drip onto the enclosure.
• Protect the switch at all times against excessive
moisture, dust, dirt, lint, construction grit and cor-
rosive vapors.
If a transfer switch is not included, one may be pur-
chased separately from a Generac Authorized Dealer.
1.3 AUTOMATIC SYSTEM OPERATION
When this generator, along with a transfer switch, has
been installed and interconnected, a circuit board in
the generator panel constantly monitors utility power
source voltage. Should that voltage drop below a pre-
set value, and remain at such a low state for a preset
amount of time, the generator cranks and starts. After
the generator starts, the transfer switch transfers load
circuits so the generator can power them.
When utility source voltage has been restored, the
switch re-transfers back to the utility source voltage
and the generator then shuts down.
Please reference the transfer switch manual for spe-
cific information.
1.4 GENERATOR AC CONNECTION
SYSTEMS
The generator was shipped from the factory with its
stator AC output leads connected in a single-phase,
3-wire generator AC connection system (Figure 1.1).
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
VAC, 60 Hertz. When the two windings are connected
in series, a 240 VAC, 60 Hertz AC output results.
Typically the two “hot” leads in the circuit are Wires
No. 11 and 44. The “Neutral” leads are the junction
of Wires 22 and 33.
Figure 1.1 - Generator AC Connection System
0
NEUTRAL
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Section 1 - General Information
Guardian Liquid-cooled 25 kW Generator
Model Rating Phase Actual Current C/B Rating* % over rating Circuit Breaker
005040-0 25,000 W 1 104.2 A 125 A 120% 125A BQ2
005053-0 20,000 W 1 83.3 A 100 A 120% 100A BQ2
005054-0 15,000 1 62.5 70 A 120% 70A BQ2
* Amp Rating of C/B structured under model.
Figure 1.2 - Main Circuit Breaker