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# Lighting circuit question

## Lighting circuit question

#1
04-01-14, 05:59 PM
Member
Join Date: Mar 2014
Posts: 5
Lighting circuit question

Hi, I have another question if anyone can help please.
I am in Edmonton Alberta and am wondering this, If I were to put ten 5" pot lights on one 15 amp circuit it would be too many, so what if the ten pot lights were having 9.5w LED bulbs ?
Does this then mean that ten lights is ok as it is less than 100 watts or does that make no difference at all and I should stick with eight on one circuit ?

I am unsure if I work with the number of outlets as the law or do I work with the 1440 watts max load on the circuit to please the inspector when it is done ?

Darren

#2
04-01-14, 06:56 PM
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Location: Jersey
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As far as I know here in the States...... there is no limit to the quantity of lights you can have on a circuit. You are limited only by the 80% continuous load requirement which is 1440 watts maximum on the circuit.

#3
04-01-14, 07:33 PM
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Join Date: Mar 2012
Location: USA
Posts: 7,458
If I were to put ten 5" pot lights on one 15 amp circuit it would be too many,
OK, I'll bite. Why?

so what if the ten pot lights were having 9.5w LED bulbs? Does this then mean that ten lights is ok as it is less than 100 watts or does that make no difference at all and I should stick with eight on one circuit?
As PJ said, there is no limit on the number of fixtures on any given circuit here in the states. Is there in Canada?

I am unsure if I work with the number of outlets as the law or do I work with the 1440 watts max load on the circuit to please the inspector when it is done?
Here, the limit is the 80% rule, or 1440W total.

Note that the maximum rated wattage of the fixtures must be used in the calculation. The lamps you have installed in them at the moment make no difference, because you can change those as soon as the inspector leaves. The code makes the assumption that no one will install lamps that draw more power than the maximum rated wattage, so that is the value used.

In your case, ten fixtures which are each rated at 144W or less would be perfectly acceptable on one 15A circuit here. Eight fixtures that are each rated at 180W or less would also be acceptable.

#4
04-01-14, 08:27 PM
Member
Join Date: Mar 2014
Posts: 5
Thank you for the response, Maybe I wrote the question wrong in as much that I meant that if I put 12 on the circuit, which seems to be the acceptable outlets allowed verses wattage.
Anyways, you answered my question spot on as I was hoping to work on wattage and not outlets, so thank you for the information.

#5
04-01-14, 10:01 PM
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Join Date: Jul 2002
Location: Maryland
Posts: 13,933
The CEC does have limits on the number of outlets on a circuit. I do not know the particulars, but I have seen a limit of 12.

#6
04-01-14, 10:05 PM
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Join Date: Mar 2012
Location: USA
Posts: 7,458
OK, that would translate into a maximum wattage rating of 120W for each of 12 fixtures on a 15A circuit.

#7
04-02-14, 05:29 PM
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Join Date: Oct 2013
Posts: 511
pcboss you're close.

OP, you have to work with the 80% rule. This allows 12A on your 15A circuit whether it be receptacles only, lights only, or a mixture of both (preferably always separate lights and power though.)
Receptacles can accept a variety of devices so you cannot calculate the load on them. Therefore each receptacle is counted as 1A, thus only allowing 12 on a 15A circuit. You can however run a 20A circuit (with appropriate sized wire, devices and breaker) for receptacles and fit 16 on it. If you run a 20A circuit though, you cannot mix it with lighting because.....

Residential lighting circuits are limited to 15A. Still following the 80% rule, you can load 12A on to it. If you know the load of your fixtures and it cannot change due to a change in bulbs, ex: the ballasts of a circuit full of T8 fluorescent fixtures, then you use you known load for your calculations. If your fixture can accept a variety of bulbs, ex: a lampholder, or in your case pot lights, then you have the same issue as the receptacles. So each fixture counts as 1A, limiting you to 12 on the circuit.

So specific to your situation, 10 pot lights is fine even without LED bulbs. The assumed load would be 1 fixture @ 1A x 10 fixtures = 10A. You could still put two more fixtures in.
And since somebody could remove your LED bulb and put in a 150W bulb instead, you cannot use your LED bulb draw in your calculation.
Your receptacles: 12 on a 15A circuit, 16 on a 20A circuit.
And if you wish to please your inspector, CEC requires a 300mm "service loop" at each box.
You would run your loomex, and staple it within 300mm of the box, then loop an extra 300mm of cable before entering the box.

You only need to do this at device boxes, not your panel.
Every receptacle except for stationary appliances (fridge, microwave) has to be tamper proof.
Any receptacles in a bedroom have to be on an expensive AFCI breaker.