The most popular option to light large areas of buildings. They come in a variety of connection types and power ratings.

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What breaker size is required?

I have three 4' foot florescent lights in line. Is a 20 amp breaker too high for these?

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Depends on where you live. Some electrical codes tell you what the maximum on a lighting breaker size is. So check with your regional code. There is a calculation that you can do to figure out the proper breaker size.


what that means is that your total amperage will equal your watts divided by volts. If you want to use a 20 amp breaker, 40 watt light bulb (pretty standard I think) and 120 volt you would figure it out like this...and just to be on the safe side,you want to use only 80% of the breaker capacity.

Amperage (per Light)= 40/120

equals 0.33 amps per light

80% of a 20amp breaker = 16amps

now divide total amps by amps per light


so with a 20 amp breaker you could supply 48 lights with a 40watt light bulbs and still have a 20% safety margin. So there is not really a breaker that is to high, just unnecessary when you only want to put 4 lights on a breaker, go smaller.

Hope this makes sense, good luck.

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Boy do those calculations bring back memories Of ET school. +


That was my feeling too :-)


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