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Cummins/Onan — －23－

A Cummins/Onan service procedure — check it applies to your exact model before use.

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Procedure

  1. 6. WATTAGE INFORMATION Some appliances need a "surge" of energy when starting. This means that the amount of electrical power needed to start the appliance may exceed the amount needed to maintain its use. Electrical appliances and tools normally come with a label indicating voltage, cycles / Hz, amperage (amps) and electrical power needed to run the appliance or tool. Check with your nearest dealer or service center with questions regarding power surge of certain appliances or power tools. ■Electrical loads such as incandescent lamps and hot plates require the same wattage to start as is needed to maintain use. ■Loads such as fluorescent lamps require 1.2 to 2 times the indicated wattage during start-up. ■Loads for mercury lamps require 2 to 3 times the indicated wattage during start-up. ■Electrical motors require a large starting current. Power requirements depend on the type of motor and its use. Once enough "surge" is attained to start the motor, the appliance will require only 50% to 30% of the wattage to continue running. ■Most electrical tools require 1.2 to 3 times their wattage for running under load during use. For example, a 5,000 watt generator can power a 1800 to 4000 watt electrical tool. ■Loads such as submersible pumps and air compressors require a very large force to start. They need 3 to 5 times the normal running wattage in order to start. For example, a 5,000 watt generator would only be able to drive a 1,000 to 1,700 watt pump. NOTE : The following wattage chart is general guide only. Refer to your specific appliance for correct wattage. To determine the total wattage required to run a particular electrical appliance or tool, multiply the voltage figure of the appliance/tool by the amperage (amps) figure of same. The voltage and amperage (amps) information can be found on a name plate which is normally attached to electrical appliances and tools. Applications Applicable Wattage (W) PX6100/e 4800 2400 RGV2800 60Hz RGV4100 1600 60Hz 1100 60Hz Incandescent lamp, Heater 2300 3600 Fluorescent lamp, Electric tool 1200 1800 Mercury lamp 800 1400 Pump, Compressor 550 850 －24－ VOLTAGE DROP IN ELECTRIC EXTENSION CORDS When a long electric extension cord is used to connect an appliance or tool to the generator, a certain amount of voltage drop or loss occurs in the extension cord which reduces the effective voltage available for the appliance or tool. The chart below has been prepared to illustrate the approximate voltage loss when an extension cord of 300 feet (approx. 100 meters) is used to connect an appliance or tool to the generator. Nominal cross section A.W.G. Allowable current No.of strands / strands dia. Resistance Current Amp. No./mm Ω/100m mm2 No. A 1A 3A 5A 8A 10A 12A 15A
  2. 0.75 18 7 30/0.18
  3. 2.477
  4. 2.5V 8V
  5. 12.5V ─ ─ ─ ─ Voltage drop
  6. 1.27 16 12 50/0.16
  7. 1.486
  8. 1.5V 5V
  9. 7.5V 12V 15V 18V ─
  10. 2.0 14 17 37/0.26

Source: manual:914-0109 Onan EGMBM Operators Manual (4-2008) .pdf. Figures and steps are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.