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Sizing a circuit/breaker and adjusting fixture wattage ratings

Sizing a circuit/breaker and adjusting fixture wattage ratings

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  #1  
Old 02-23-16, 05:47 PM
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Sizing a circuit/breaker and adjusting fixture wattage ratings

Hi all, I'm new to this but excited to join your community!

I am planning to install some recessed lighting. I understand that if my circuit is sized for (as an example), 1.5kw, I can have 15 100-watt fixtures.

However, I plan to use LED bulbs, so they will actually only be using 10 watts each. Can I install 20 fixtures, but replace the 100-watt sticker with a 10-watt sticker? In other words, is it legal to reduce the fixture rating?

Yes, I could just buy the LED fixtures to begin with. However, I was looking at some LED vs. incandescent fixtures, the price difference is over $20 -- way more than an LED bulb. These particular fixtures are exactly the same, except one comes with a replaceable LED bulb and has a 4.5w rating, and the other comes with incandescent and has a 50w rating.
 
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  #2  
Old 02-23-16, 06:40 PM
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Welcome to the forums!

No. You need to plan for the worst case scenario which is 100 watts. The lights could change owners at any time and the next person might not like the lights you choose.

If you want to install more lights on the circuit you could use a 20 amp circuit, but I would just install a 2nd circuit, or a multi-wire circuit and a two pole breaker.
 
  #3  
Old 02-23-16, 06:48 PM
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The worst case is the rated wattage, right? So if I put a sticker that says 10w and a new homeowner uses 100w, they are overlamping. I appreciate your answer, it just seems like a bit counter-intuitive.
 
  #4  
Old 02-24-16, 05:13 PM
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So if I put a sticker that says 10w and a new homeowner uses 100w, they are overlamping.
Use the maximum rated wattage of the fixture.
 
  #5  
Old 02-24-16, 05:36 PM
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An individual can not change the rating of an approved device.
To do so would invalidate any approvals it had.
 
  #6  
Old 02-25-16, 02:29 PM
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So basically I get to pay an extra $20/lamp just to get the official 5w rating? I don't see a safety issue with reducing a lamps rating, only increasing. Anyone have a citation for this?
 
  #7  
Old 02-25-16, 03:08 PM
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There is nothing preventing you from adding a sticker stating a maximum wattage of 5 on your fixtures but it is a meaningless act as the only official rating is the one affixed by the manufacturer.
 
  #8  
Old 02-25-16, 03:38 PM
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Essentially it's the entire first half of Article 110 of the NEC "Requirements for electrical installations". To paraphrase, all installed electrical equipment and material must be approved and listed by a nationally recognized testing laboratory (NRTL) and cannot be altered from it's original design or used in a way not intended by the manufacturer. Local inspectors are generally granted the authority to override this requirement on a case-by-case basis, but ultimately it's their choice whether to do so. It also references back a lot to art 100 and to the definitions. Far too lengthy to post that all here.
 
  #9  
Old 02-25-16, 05:05 PM
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Thank-you for citing my assertion!

I help check approvals for any electrical device or fixture that comes into my workplace.
What Ben quoted pretty much applies in any jurisdiction.
You can do anything that you want but asked and got several accurate and professionally delivered opinions.

Our inspectors would not approve an installation with either a missing or improper sticker.
The inspection department will send someone trained to perform a special inspection and for $135.00 for each device will give it a special inspection certificate if it meets his/her approval.

A lot cheaper than $20.00/light.
 
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