Lighting continious or not?

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Rouse

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I am studing for an exam so I have been doing alot of practice qusetions several of which are sizing feeders. I have come across qusetions where the solution says that lighting is continious and must be multiplied by 125% ex. banks. But I have also come across questions where the solution does not say to multiply the lighting load by 125% ex. a dwelling unit. My question is are there times when you have to size feeders when the lighting is not considered continious or are these questions that don't multiply the lighting load by 125% wrong?
 
Load calcs for non dwelling units and dwelling units are very different.
Non dwelling unit lighting is considered a continuous load
Dwelling units VA/SF includes lights and receptacles.
For your exam, you should be able to do a dwelling unit load calc in just a few minutes.
 
So you are saying the dwelling unit calculated lighting (and recptical) load is not considered continious it is just the 3va per square ft?
 
To add on to my last post, if the dwelling lighting is not continuous, is it because 220.14(j) says the general-use receptacles are included and those being general-use are not considered continious? (article 100 - continuous load)
 
Usually in commercial they are on for more than 3 hours (hence continuous load). Usually in dwelling units they are not ON continuously.
 
Rouse said:
To add on to my last post, if the dwelling lighting is not continuous, is it because 220.14(j) says the general-use receptacles are included and those being general-use are not considered continious? (article 100 - continuous load)
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There is really nothing in the NEC that states whether a residential circuit is continuous or not and IMO does not need to be calculated at 125%. A dwelling will rarely see every light on a circuit running for 3 hours all the time. Sure occasionally it may but generally it is not an issue. IMO, it is wise not to load a lighting circuit to the max, but that is design and not for calculation purposes.
 
Dennis Alwon said:
There is really nothing in the NEC that states whether a residential circuit is continuous or not and IMO does not need to be calculated at 125%. A dwelling will rarely see every light on a circuit running for 3 hours all the time. Sure occasionally it may but generally it is not an issue. IMO, it is wise not to load a lighting circuit to the max, but that is design and not for calculation purposes.
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So you think for Minnesota state board of electricity testing purposes, dwelling unit lighting is not continious and does not need to be multiplied by 125%?
 
That is what I think, and if I were taking the test that is the approach I would use. But that is not important. What is important is what the person who wrote the test question thinks. None of us are going to know that.
 
Thanks Charlie it makes alot of sense that dwelling lighting is not continoius and your right I suppose it is up to the person who wrote the test but that is the way I am going to calculate it.
 
I just passed my Masters today. I had the same question:

All my exam prep calculations say to take lighting at 125% when it's continuous, as in a commercial building, but I can't find it anywhere in article 220 Load Calculations.

I thought Table 220.12 load minus Table 220.42 Demand Factor was THE minimum lighting load.

The exam prep questions do not ask for:
1) feeder conductor size discussed in 215.2(A)
2) OCPD
3) Servicer
Where loads are taken at 125% when continuous.

What is the code citation I am missing?
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LINK

I decided to figure continuous even if the question asked for demand only;
Not Branch or feeder conductor, service, or OCPD.
In fact, today I had a church lighting question and needed to calculate how many ckts for the sq footage given -per NEC 220.12 General Lighting demand. I figured continuous -there was an answer choice for non-continuous or continuous. Continuous was right. I went back and forth trying to decide if the church service was 1 hour, or more than 3 hours by the time it cleared out. Subjective, huh?

I'd add that I think the code is ambiguous. Continuous deration IS figured in the Annex-D but that's informational only and has a contingency for use.
 
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