WATTAGE CALCULATIONS

IMPORTANT

Never exceed the rated capacity of your generator. Serious damage to the generator or appliance could result from an overload.

1.Starting and running wattage requirements should always be calculated when matching a generators wattage capacity to the appliance or tool.

2.There are two types of electrical appliances that can be powered by your generator:

A.Items such as radios, light bulbs, television sets, and microwaves have a "resistive load". Starting wattage and running wattage are the same.

B.Items such as refrigerators, air compressors, washer, dryer, and hand tools that use an electrical motor have an "inductive load". Inductive load appliances and tools require approximately 2 to 4 times the listed wattage for starting the equipment. This initial load only lasts for a few seconds on start-up but is very important when figuring your total wattage to be used.

C.Always start your largest electric motor first, and then plug in other items, one at a time.

NOTE: On 120-volt loads the maximum starting wattage should NOT

exceed one half of the rated generator wattage. Example: a 5000 rated wattage generator = 2500 maximum starting wattage.

DETERMINING WATTAGE REQUIREMENTS

Before operating this generator list all of the appliances and/or tools that are going to operate at the same time. (Then determine the starting wattage requirements and the running wattage requirements by following example and/or refer to household wattage calculator.)

1.First total the running wattage of all appliances and/or tools that will be operated at the same time.

 

 

Running Watts

Starting Watts

Example 1:

 

 

 

 

Lights

=

100 Watts

0

Television

=

300 Watts

0

Slow Cooker

=

250 Watts

 

0

 

TOTAL

=650 Watts

0

2.Next the starting wattages of any appliances and/or tools that will start and stop during operation.

 

Running Watts

Starting Watts

Example 2:

 

 

Small Refrigerator

500 Watts

2000 Watts

TOTAL

=500 Watts

2000 Watts

3.The running wattage of examples 1 & 2 totals 1150 watts. The starting wattage of the small refrigerator is 2000 watts which is 1500 watts more than the running watts. Take this difference of 1500 starting watts from the refrigerator and add to the total running watts of 1150.

Example 3:

1500

Starting Watts

 

1150

Running Watts

TOTAL

=2650 Total Watts

Generator must have a maximum capacity of at least 2650 watts.

D27245

18- ENG

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Porter-Cable D27245-028-0 Wattage Calculations, Determining Wattage Requirements, Running Watts Starting Watts