Section 1
GENERATOR FUNDAMENTALS
FIELD BOOST
When the engine is cranked during startup, the engine's starter contactor is energized closed. Battery current is then delivered to the starter motor and the engine cranks.
Closure of the starter contactor contacts also delivers battery voltage to Pin 13 of an Engine Controller cir- cuit board. The battery current flows through a 47 ohm, 2 watt resistor and a field boost diode, then to the Rotor via brushes and slip rings. This is called “Field Boost” current.
Field boost current 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 current 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 out- put. If Rotor residual magnetism alone is suffi- cient to turn the Regulator on loss of Field Boost may go unnoticed. However, If residual magnet- ism 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 commen- surate with the Rotor's residual magnetism (about
GENERATOR AC CONNECTION SYSTEM
These
You can use your generator set to supply electrical power for operating one of the following electrical loads:
•QUIETPACT 55G & LP: 120 and/or 240 volts, sin- gle phase, 60 Hz electrical loads. These loads can require up to 5500 watts (5.5 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.
•QUIETPACT 65G & LP: 120 and/or 240 volts, sin- gle phase, 60 Hz electrical loads. These loads can require up to 6500 watts (6.5 kW) of total power, but cannot exceed 54.1 AC amperes of current at 120 volts or exceed 27 AC amperes at 240 volts.
•QUIETPACT 75G & LP: 120 and/or 240 volts, sin- gle phase, 60 Hz electrical loads. These loads can require up to 7500 watts (7.5 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 exces- sively high electrical loads may damage the gen- erator and may shorten its life. Add up the rated watts of all electrical lighting, appliance, tool and motor loads the generator will power at one time. This total should not be greater than the wattage capacity of the generator. 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.
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 120V across the generator output terminals. Figure 1.8, page 7, shows the generator lead wire connections for 120VAC ONLY.
2.120/240 VAC loads — one load with a maximum total wattage requirement equal to the generator’s rated power output, and 240V across the generator output terminals; or two separate loads, each with a maximum total wattage requirement equal to half of the generator’s rated power output (in watts), and 120V across the generator output terminals. Figure 1.9 on page 7, shows the generator lead wire connections for 120/240 VAC loads.
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 rat- ings are as follows:
| Model | Circuit Breaker 1 | Circuit Breaker 2 |
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| QuietPact 55 | 30A | 20A |
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| QuietPact 65 | 30A | 30A |
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| QuietPact 75 | 35A | 35A |
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