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OPERATING TIPS
RATED VERSUS ACTUAL CURRENT DRAW OF EQUIPMENT
Most electrical tools, appliances and audio/video equipment have labels that indicate the power consumption
in Amps or Watts. Be sure that the power consumption of the item you wish to operate is less than inverter’s
power. (If the power consumption is rated in Amps AC, simply multiply by the AC Volts (115) to determine the
approximate Wattage). The inverter will shut down if it is overloaded. The overload must be removed before
the inverter will restart. Resistive loads are the easiest for the inverter to run. However, larger resistive loads,
such as electric stoves or heaters, usually require more wattage than the inverter can deliver. Inductive loads,
such as TV’s and stereos, require more current to operate than do resistive loads of the same wattage rating.
Induction motors, as well as some televisions, may require 2 to 6 times their wattage rating to start up. The
most demanding in this category are those that start under load, such as compressors and pumps. To restart the
unit after a shutdown due to overloading, remove the overload if necessary turn the power switch OFF,
wait
for at least 3 minutes
and then switch ON again.
SIZING CHART FOR TYPICAL LOADS THAT REQUIRE HIGH STARTING SURGE
The manufacturers’ specifications of the appliances and devices indicate only the running power required.
The surge power required by some specific types of devices has to be checked with the manufacturer, actually
tested or guessed at best.
The Table below lists some common loads that require high surge power on start up. A “Sizing Factor” has
been recommended against each which is a Multiplication Factor to be applied to the rated running Watt
rating of the load to arrive at the continuous power rating of the inverter (Multiply the running Watts of the
device / appliance by the Sizing Factor).
TYPE OF DEVICE OR APPLIANCE
SIZING FACTOR
Air conditioner
5
Refrigerator / Freezer (Compressor based)
5
Air Compressor
4
Sump Pump / Well Pump / Submersible Pump
3
Dishwasher
3
Clothes Washer
3
Microwave (In cases where the rated output power is the cooking power)
2
Furnace Fan
3
Industrial Motor
3
Portable Kerosene / Diesel Fuel Heater
3
Circular Saw
3
Bench Grinder
3
Incandescent / Halogen / Quartz Lamps
3
Laser Printer / Other Devices using Quartz Lamps for heating
3
Switched Mode Power Supplies
3
Photographic Strobe / Flash Lights (with respect to its Watt Sec rating)
4 *
* In the case of photographic strobe / flash unit, the RMS surge power of the inverter should be more than 4 times the Watt Sec
rating of the unit.
