Primepact 50 & 50LP RV Owner's Manual D7431 - Electric Generators

Section 2 – OperationPRIMEPACT 50 Recreational Vehicle GeneratorWhen the heat riser is in the WINTER (up) position,air is drawn from the lower intake tube, which ispositioned to draw the heated air near the exhaustmanifold.To prevent carburetor icing, the owner/operatorshould physically position the heat riser to the properposition dependent on the temperature.◆ 2.8.1 DO NOT OVERLOAD THE GENERATORYou can read the rated wattage/amperage capacity ofyour generator on the generator data decal (seeSection 1.1 on Page 4).Applying electrical loads in excess of the unit’s ratedcapacity will cause the engine/generator to automaticallyshut down.To avoid overloading, add up the wattage of all connectedelectrical lighting, appliance, tool and motorloads. This total should not be greater than the generator’srated wattage capacity.• Most lighting, appliance, tool and motor loads indicatetheir required watts on their nameplate ordata plate. For light bulbs, simply note the wattagerating of the bulb.• If a load does not show its rated wattage, multiplythat load’s rated VOLTS times AMPS to obtainWATTS.• Induction type motors (such as those that run thevehicle’s furnace fan, refrigerator, air conditioner,etc.) need about 2-1/2 time more watts of power forstarting than for running (for a few seconds duringmotor starting). Be sure to allow for this when connectingelectrical loads to the generator. First, figurethe watts needed to start electric motors in thesystem. To that figure, add the running wattages ofother items that will be operated by the generator.• Do not apply heavy electrical loads for the first twoor three hours of operation.2.9 PROTECTION SYSTEMSFigure 2.4 – Low Oil Pressure andHigh Temperature Switches◆ 2.9.3 FIELD BOOSTThe Controller Circuit Board houses a field boostdiode and resistor that are not part of the automaticchoke circuit. These two components are part of a“field boost” circuit (Figure 2.5). During enginecranking only, a positive DC (battery) voltage is deliveredthrough the diode, resistor, brushes and sliprings, and the generator rotor. Application of thisvoltage to the rotor “flashes the field” whenever it isstarted. Flashing of the field each time the generatorstarts makes sure that a sufficiently strong magneticfield is available to produce “pickup” voltage in thestator windings.Figure 2.5 – Field Boost Circuit◆ 2.9. LOW OIL PRESSURE SWITCHThis switch (Figure 2.4) has normally closed (N.C.)contacts that are held open by engine oil pressure duringcranking and operating. Should oil pressure dropbelow a preset level, switch contacts close, and theengine automatically shuts down. The unit should notbe restarted until oil is added.◆ 2.9.2 HIGH TEMPERATURE SWITCHThis switch (Figure 2.4), which has normally open(N.O.) contacts, is mounted near the oil filter. Thecontacts close if the temperature should exceedapproximately 293º F (145º C), initiating an engineshutdown.10 Generac ® Power Systems, Inc.