Test prep question

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nickelec

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I'm going through some test prep questions and can not find this in the book some help would be appreciated
It's question#5 regarding stair lighting
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I think you need a better test prep book.

I can say that stair lighting should be considered a continuous load. That means you have to limit the load of a 15 amp circuit to 12 amps. That equates to 1440 VA. This does not match any of the answers. But it does rule out answers B and D.

That’s as far as I can take this.

 
I would guess 'B', in that 10*180VA per outlet per 220.14(L), but I agree with Charlie in that the wording is poor here.
 
Either A or C would be allowed as it is less that 1440 VA. It could be any number of lights as long as it does not exceed 1440 VA total continuous load. If you had, say, 10 VA LED lights you could have 144 of 'em on the circuit. The 180 VA limit only applies to receptacles.
 
Who says the lighting outlets have to be continuous? I would not think that the 125% comes in to play here if we look at 220.14(D) -"an outlet supplying luminaires shall be calculated based on the maximum volt-ampere rating of the equipment and lamps for which the luminaire is rated". Unfortunately, we do not know the luminaires max VA, so we cannot use this to calculate the outlet VA. Because of this, we have to consider these outlets to be under 220.14(L), which covers all of our unknowns. We do not know where these stairs are located and we have no obligation to consider them a continuous load in my opinon, in the case of this problem that is.

There's an interesting forum below that somewhat highlights along this topic (towards the bottom of it)

http://forums.mikeholt.com/showthread.php?t=187115
 
I agree with Texie-- 180 is for receptacles. Lights are to be used at the wattage of the fixtures....So to ask how many outlets is just wrong...Assume that this is not residential? Bad question
 
Outlet - A point on the wiring system at which current is taken to supply utilization equipment. In the context of this question, I do not believe we are talking about receptacles specifically. An outlet can be a J-box connection to a light. If we ignore the word receptacle, and look back at 220.14(L), it says other outlets not covered in 220.14(A) through (K) shall be calculated based on 180 volt-amperes per outlet. At no point in there does it say to consider the lighting outlet as a receptacle, or to consider it a continuous load.

By this, I would take 15A x 120V = 1800VA.

1800VA / 180VA per outlet** = 10 outlets.

We have to ignore 220.14(D) because we do not know the specified wattage of any luminaire connected to the outlet.

Basically, all receptacles are outlets, but not all outlets are receptacles.
 
charlie b said:
I think you need a better test prep book.

Click to expand...

You're right. I knew that the answer was C because I remembered studying this in apprentice school in the late 80's. After some searching I was able to dig out my old codebook. This is from the 1987 NYC Electrical Code. {B30-152.0} I'll post the actual code later.
 
Now that answer does not exist does it you would be able to load the ckt with however many wats it's rated for so it's definitely a protestable question if it's on the test because we go off the 2008

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nickelec said:
Now that answer does not exist does it you would be able to load the ckt with however many wats it's rated for so it's definitely a protestable question if it's on the test because we go off the 2008

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Click to expand...

My previous comments were based strictly on the NEC. I would say that you have to go by the NYC code which according to what infinity posted, the answer is clearly "C".
 
Can any of you gentlemen recommend a good source for DC and ac motor prep

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