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1.1 GENERATOR
This equipment is a liquid-cooled, engine-driven
generator set. The generator is designed to supply
electrical 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
operation of 120 and/or 240VAC, single-phase loads.
This model is available and rated as follows:
Model 005031-2: Provides 25,000 watts (25 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 trans-
fer switch. The transfer switch must effectively
isolate the electric system from the utility distri-
bution system when the generator is operating
(NEC 701). Failure to isolate an electrical system
by such means results in damage to the genera-
tor and may also result in injury or even death
to utility power workers due to backfeed of
electrical energy.
1.2 TRANSFER SWITCH
This generator system is intended to be used with a
matched automatic transfer switch. It may be sup-
plied 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
necessary. 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 an Authorized Dealer.
1.3 ATS MODE (AUTOMATIC
OPERATION)
When this generator, along with a transfer switch, has
been installed and interconnected, a circuit board in
the generator control panel constantly monitors utility
power source voltage. Should that voltage drop below a
preset value, and remain at such a low state for a pre-
set 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
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NEUTRAL
1.5 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 in Figure 1.2.
Section 1 - General Information
Liquid-cooled 25 kW Generators
Model Rating Phase Actual Current C/B Rating* % over rating Circuit Breaker
005031-2 25,000 W 1 104.2 A 125 A 120% 125A BQ2
* Amp Rating of C/B structured under model.
Figure 1.2 - Main Circuit Breaker