Longer extension cord means lower voltage. Seriously.

- April 24, 2013

I know, it sounds like another version of the ‘did you know gullible was not in the dictionary?’ trick, but it’s true! Even though copper is a champion conductor, the longer the run of wire, the more resistance incurred – this produces heat which does damage to the cord AND the item plugged into it. Furthermore, if you are using something that draws a lot of amperage (like a power tool) then a voltage drop in the cord doesn’t allow the power tool to run at full speed causing it to heat up and inflict damage to itself. This can also damage the extension cord, overload your circuit breaker and generally ruin your entire day.

For the love of all that is electrical, don’t do this:


Use the useful chart below to work out which extension cord you need, using the minimal length you can comfortably get away with.


If the rating for the electrical device and the cord are both listed in amps, simply select an extension cord that exceeds the amperage requirements of the device. If you plan to connect multiple devices to the cord at the same time, add up the current requirements for each device. (The power requirements for some devices are listed in watts, rather than amps. In this case, use this formula to convert the rating to amps: Amps = Watts/110).

If you have any doubts then please reach out to us here at Massive, send an email to Howie who will be happy to help you out with any questions or guidance you might need.

Happy extending!

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