7.
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Generally, the power ratingof an electrical appliance indicates the amountofwork that canbe done by it.
The electricpowerrequiredforoperating an electricalappliance is not alwaysequaltotheoutput wattage of the appliance. The electrical appliances generally have a label showing their rated voltage, frequency, and power consumption (input wattage). The power consumption of an electrical appliance is the power necessary for using it. When using a generator for operatingan electrical appliance,the power factor and starting wattagemust be taken into consideration.
In order to determine the right size generator, it is necessary to add the total wattage of all appliances to be connected to the unit.
Refer to the followings to calculate thepower consumption of each applianceor equipment by its type.
Incandescent lamp, heater, etc. withapower factorof 1.O
Total power consumption must be equal toor less than the rated outputof the generator. Example: A rated 1OOOW generator can turnten lOOW incandescent lamps on.
Fluorescent lamps, Motor driven tools,light electrical appliances, etc. witha smaller power factor
Select a generator with a rated output equivalent to 1.2 to 2 times of the power consumption of the load. Generally the starting wattageof motor driven tools and light electrical appliances are 1.to2 3 times lager than theirrunning wattage.
Example: A rated 250W electric drill requires a400W generator to start it.
NOTE 7: If a power factor correction capacitor is not applied to the fluorescent lamp, the more power shall be required todrive the lamp.
NOTE 2: Nominal wattage of the fluorescent lamp generally indicates the output wattage of the lamp.
Therefore, if the fluorescentlamp has no special indication as to the power consumption, efficiency should be taken into account as explaineditem (5) on the following page.
Mercury lampswith a smaller power factor
Loads for mercury lamps require 2 3totimes the indicated wattage during
A rated 1OOOW generator canpower one 400W mercury lamp
Initially loaded motor driven appliances such as water pumps,compressors,etc.
These appliances require large starting wattage whichis 3 to 5 times of running wattage. Example: A rated 9OOW compressor requires a4500W generator to drive it.
NOTE 1:
NOTE 2:
starting powerdepending on the kind
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