Determining the power required by an appliance Maximum vs. Rated Power To determine your basic home power needs, start with these three questions: Do you use city or well water? Well pumps require a larger 240 volt generator (3800 watts or above). Is your heating system electric, heat pump, or gas or oil forced air? Gas or oil forced air systems can get by with a very small generator – as little as 2500 watts.  The power needed is based on the size of the furnaceSee below for details. Electric furnaces and heat pumps typically need 15,000 watts or more to run and cannot be powered by a portable generator. Is your hot water heater electric, gas, or oil fired? Gas or oil fired heaters use less power – as little as 2500 watts. Electric heaters often require at least 4500 watts. Homeowners can often power most household appliances using between 3000 and 6500 If your home has a smaller furnace and city water, you can generally expect that

3000-5000 watts will cover your needs. If you have a larger furnace and/or a well pump, you will likely need a 5000 to 6500 watt generator. The primary factor you need to consider is the size of your AC unit(s). Campers, Tailgaters, and Boaters: Industrial power needs range widely, based on what kind of tools you are using. To determine your power needs, start with our wattage estimation guide can help you to build a quick estimate.  choose the tools you will be using and add up the wattage. Keep in mind that wattage required for starting a tool or appliance with a motor will be much higher than the watts required to run the device.  starting vs running wattage below. If you need the wattage on a specific tool, see our section on determining the power needed by an appliance below. See our section on power management to learn how to use a smaller generator to power more. Most appliances and electric motors list their power requirements in amps.

Use an appliance load tester to determine the exact power needed for a variety ofHonda offers a handheld load tester that is perfect for thisThis inexpensive tool is available from any Our Wattage Estimation Guide also provides average wattage for many applications. Appliances frequently list their power requirements in amps. their output in watts. Fortunately, it’s easy to convert from one to the other: Most appliances use 120 volts. wattage estimation guide for a list of 240 volt applications. If you have two of the numbers (e.g. volts, amps) then you can find out the otherThis can help you to determine the rated power that you’ll need Some appliances require extra power to start up, while others maintain the same To calculate your power needs correctly, you need to know which kind of load you(A load is defined as the device that you are powering.) There are two kinds of loads: Resistive loads are pretty simple:  they require the same amount of power to

both start and run the equipment. Many resistive loads are involved in heating or making heat of some kind. Examples of resistive loads include: Reactive loads contain an electric motor, which requires additional power to start,right size ac unit my house but significantly less power to run once it gets going. what ton of ac unit do i need is 3 times the amount of power to run the application.   best mini ac unit Some household appliances, like a furnace or refrigerator, have internal fans thatExtra wattage/power is needed to start the fan each time. Refrigerators also have a defrost cycle that requires power in addition to the compressor and fans. Reactive loads may also require additional power when the electric

motor begins to work.  For example, when a saw begins cutting wood, its powerThis is not applicable for most household appliances. Some devices are labeled or promoted with a power number. For example, a hair dryerThis means the hair dryer itself produces 1000 wattsBut the amount the hair dryer uses from a power outlet is always more than it produces in heat. This is because the device’s energy use is Another example is a microwave oven. It may be marketed as "1100 watt oven" and indeed produce 1100 watts of cooking power, but it will require more than that For some appliances, you can determine the power needed by looking at the data tag supplied by the electric motor manufacturer. All electrical motors should have a data tag attached to their bodies that give volts, amps, phase, cycles, hp, and sometimes a code. To determine the wattage needed, use Amps x Volts = Watts Generators are often advertised at the maximum wattage they can produce.