inverter to shut down or the fuse to blow. Repeated use of excessive power draw can cause failure of
the power inverter.
How to calculate power usage. Most products have a power rating on them such as 45 watts.
Others may be marked with their current draw, such as .9 amps. To convert the current to watts
multiply the current by 115. (Example: .9 amps x 115 = 104 watts)
Typical Power Usage Chart
Typical Appliance Current Draw TV/VCR combo 120 watts 19” TV 160 watts Blender 650 watts Small power drill 3/8” 500 watts Toaster 850 watts Vacuum 900 Some products draw a high surge current to start up. If the appliance does not operate and the
inverter turns off, you may need a larger inverter. Also, check that the battery and the 12 volt wiring
to the inverter is large enough to handle the current draw and that the battery is fully charged.
Important: The power inverters may not operate some appliances designed to produce
heat such as hair dryers, heaters, toasters and coffee makers. Always check the power
rating before using these kinds of products to be sure they do not exceed the power
capability of the inverter.
Battery Life
Important: The power inverter can draw lots of amps from your car’s battery when operating. If you
are using it for extended periods of time, you will want to operate your car occasionally to maintain
the charge in your car’s battery. In addition, the power inverter will also draw a small current, less
than 0.1 amp, when turned off and not operating. Therefore, it should be disconnected from your
car’s battery if your vehicle will not be used for more than a day. The following chart shows typical
operation time for typical car batteries with the engine not running for various loads. Check the size
of your battery.
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