Generac Power Systems 5413, 5412, 5411, 5415, 5414, 5410 Field Boost, Generator AC Connection System

Section 1

GENERATOR FUNDAMENTALS

Field Boost

When the engine is cranked during startup, the starter contactor is energized closed. Battery voltage is then delivered to the starter motor and the engine cranks.

During cranking, battery voltage flows through a resis- tor and a field boost diode in the Printed Circuit Board, then to the Rotor via brushes and slip rings. This is called “Field Boost” voltage.

Field boost voltage is delivered to the Rotor only while the engine is cranking. The effect is to “flash the field” every time the engine is cranked. Field boost voltage helps ensure that sufficient “pickup” voltage is avail- able on every startup to turn the Voltage Regulator on and build AC output voltage.

NOTE: Loss of the Field Boost function may or may not result in loss of AC power winding output. If Rotor residual magnetism alone is sufficient to turn the Regulator on, loss of Field Boost may go unnoticed. However, if residual magnetism alone is not enough to turn the Regulator on, loss of the Field Boost function will result in loss of AC power winding output to the load. The AC output voltage will then drop to a value commensurate with the Rotor’s residual magnetism (about 7-12 VAC).

Generator AC Connection System

These air-cooled generator sets are equipped with dual stator AC power windings. These two stator wind- ings supply electrical power to customer electrical loads by means of a dual 2-wire connection system.

Generators may be installed to provide the following outputs:

1.120 VAC loads only — one load with a maximum total wattage requirement equal to the generator’s rated power output (in watts), and 120 VAC across the generator output terminals. Figure 1-8, page 7, shows the generator lead wire connections for 120 VAC ONLY.

2.120/240 VAC loads — one load with a maximum total wattage requirement equal to the generator’s rated power output, and 240 VAC across the gen- erator output terminals; or two separate loads, each with a maximum total wattage requirement equal to half of the generator’s rated power out- put (in watts), and 120 VAC across the generator output terminals. Figure 1-9 on page 7, shows the generator lead wire connections for 120/240 VAC loads.

You can use your generator set to supply electrical power for operating one of the following electrical loads:

•RV 45G & LP: 120 and/or 240 volts, single phase,

60 Hz electrical loads. These loads can require up to 4500 watts (4.5 kW) of total power, but cannot exceed 45.8 AC amperes of current at 120 volts or exceed 22.9 AC amperes at 240 volts.

•RV 55G & LP: 120 and/or 240 volts, single phase,

60 Hz electrical loads. These loads can require up to 5500 watts (5.5 kW) of total power, but cannot exceed 54.1 AC amperes of current at 120 volts or exceed 27 AC amperes at 240 volts.

•RV 65G & LP: 120 and/or 240 volts, single phase,

60 Hz electrical loads. These loads can require up to 6500 watts (6.5 kW) of total power, but cannot exceed 62.5 AC amperes of current at 120 volts or exceed 31.2 AC amperes at 240 volts.

*Caution! Do not overload the generator. Some installations may require that electrical loads be alternated to avoid overloading. Applying excessively high electrical loads may damage the generator and may shorten its life. Add up the rated watts of all electrical lighting, appli- ance, tool and motor loads the generator will power at one time. This total should not be greater than the wattage capacity of the gen- erator. If an electrical device nameplate gives only volts and amps, multiply volts times amps to obtain watts (volts x amps = watts). Some electric motors require more watts of power (or amps of current) for starting than for continuous operation.

Line breakers (120 Volts Only):

Protects generator’s AC output circuit against overload, i.e., prevents unit from exceeding wattage/ amperage capacity. The circuit breaker ratings are as follows:

Model	Cir. Breaker 1	Cir. Breaker 2	240 Volt
RV 45	20A	20A	20A 2P
RV 55	20A	30A	25A 2P
RV 65	30A	30A	30A 2P

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