Generac 004912-0, 004912-1, 004913-0, 004913-1 1.1GENERATOR, 1.3AUTOMATIC SYSTEM OPERATION

Section 1 - General Information

Centurion Liquid-cooled 15 kW and 25 kW Generators

1.1GENERATOR

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 factory-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.

These models are available. They are rated as follows:

Model 004912 : Provides 15,000 watts (15 kW) of single-phase power.

Model 004913: 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 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 workers due to backfeed of electrical energy.

1.3AUTOMATIC SYSTEM OPERATION

When this generator, along with its 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 preset 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 specific information.

1.4GENERATOR AC CONNECTION

SYSTEMS

The generator was shipped from the factory with its stator AC output leads connected in a single-phase, three-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 120VAC, 60 Hertz. When the two windings are connected in series, a 240VAC, 60 Hertz 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

1.2TRANSFER SWITCH

This generator system includes a matched automatic transfer switch which is intended to be used in conjunction with the Centurion generator. It is supplied in a NEMA 3R enclosure. The NEMA 3R enclosure is weather resistant and can be used indoors or outdoors. Follow these rules:

•Install the transfer switch on a firm, sturdy supporting 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 corrosive substance might drip onto the enclosure.

•Protect the switch at all times against excessive moisture, dust, dirt, lint, construction grit and corrosive vapors.

•It is highly recommended to utilize a Generac/Centurion transfer switch with this generator or it may void the warranty.

NOTE:

Rated power of generator is subject to and limited by such factors as ambient temperature, altitude, engine condition, and other factors. Engine power will decrease about 3% for each 1000 feet above 3000 feet and will decrease an additional 1.5% for each 10°F above 77°F. Maximum output power of the generator is limited by maximum engine power.

4 Generac® Power Systems, Inc.