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Total Lighting Load & Current

  1. Aug 16, 2013 #1
    It's been a while since I had my last circuits class, so I'm just looking for some verification on my calculations. I have a series of lights that I want to combine to 1 circuit (if possible).

    Each light fixture has 2 bulbs, and I have a total of 12 fixtures, meaning 24 bulbs. I am using 32W fluorescent light bulbs. To find the total load I multiply the 32W per bulb by 24 (# of bulbs) and get 768W. Now I want to find the current, so I divide the power by voltage. 768W/120V=6.4 Amps.

    The lights will be running on a 20A breaker, and code allows me to load the break to 0.8*Rating. 0.8*20=16A. So the 6.4 Amps that I will be pulling, will be safely less than the 16A I should not exceed. Does that sound right, or is there something I'm forgetting?

  2. jcsd
  3. Aug 16, 2013 #2


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    Staff: Mentor

    Since they are flourescent lamps, do you know what their startup current is? That may end up giving you a higher peak/initial current.
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