Generac Power Systems 005012-1 owner manual Generator, Transfer Switch, Automatic System Operation

Section 1 - General Information

40kW Liquid-cooled 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 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.

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.

1.2TRANSFER SWITCH

This generator system is intended to be used with the manufacturer's transfer switch. It will be avail- able 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:

1.3AUTOMATIC 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 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 volt- age and the generator then shuts down.

Please reference the transfer switch manual for spe- cific 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 sup- ply 120VAC, 60 Hertz. When the two windings are connected in series, a 240VAC, 60 Hertz AC output results. Typically the two HOT leads in the circuit are wires 11 and 44. The NEUTRAL leads are the junction of Wires 22 and 33. The NEUTRAL is not grounded.

•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.

An Authorized Dealer can supply an appropriate transfer switch for the generator.

Figure 1.1 - Generator AC Connection System

1.5MAIN CIRCUIT BREAKER

The generator’s main circuit breaker is included with the unit as shipped from the factory. The breaker for this unit is described in Figure 1.2.

Figure 1.2 - Main Circuit Breaker

Model	Rating	Phase	Actual Current	C/B Rating*	Circuit Breaker
005012-1	37,000 NG	1	154.2	200	200A QN2
	40,000 LP	1	166.7	200	200A QN2
		* Amp Rating of C/B structured under model.

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