Kitchen & Bath Luminary Circuits ...

[arjo_reich]

I know the forum is not for the DIY types however I've been lurking for about five months and reviewing the NEC diligently and I have question I was hoping I could get clarification on...

If a home is wired so that all luminaries are not on the same circuits as any non-luminary device, can the bathroom lighting share the same AFCI circuit for the luminaries in the bedrooms? The same question can be applied to the kitchen luminary and an adjoining hallway.

I know that for nearly everything else in those rooms (kitchen and bath) the circuits are dedicated to those rooms, but I just cannot find the article that will say yea or nea for luminaries only...

Thank you in advance,

R. Joe Reich

Article references greatly appreciated...

[ July 11, 2005, 12:15 PM: Message edited by: arjo_reich ]

 

[al hildenbrand]

Re: Kitchen & Bath Luminary Circuits ...

You won't find a reference.

If it is not prohibited by the language of the NEC, it is allowed.

 

[southernboys]

Re: Kitchen & Bath Luminary Circuits ...

I dont see anything that would prohibit this. I may not do it myself personally just seems like it would add one more box to check if the afci starts tripping

 

[arjo_reich]

Re: Kitchen & Bath Luminary Circuits ...

Originally posted by southernboys:
I dont see anything that would prohibit this. I may not do it myself personally just seems like it would add one more box to check if the afci starts tripping

Thank you, I appreciate it. I agree that the wiring scheme seems a little unorthodox however many home automation systems list an optimal environment being such that...

1. Controlled luminary devices are not on circuits shared with non-luminary devices.

2. Large electrical motors - disposal, dishwasher, washer / dryer, etc. - are not on circuits shared with devices (mostly receptacles) which will be controlled.

---
In regards to the AFCIs, I will have three 20 AMP AFCI circuits.

1. three ceiling fans & one bathroom luminary.
2. outlet receptacles for two small bedrooms.
3. five smoke detectors & one CO detector, but since two of them are in bedrooms, AFCI was the only choice.

If my load calculations are correct, even though they're 20 AMP circuits, none of them will carry more than a 12-14 AMP continous load so I should be well within the 85% rule of thumb.

 

[physis]

Re: Kitchen & Bath Luminary Circuits ...

There is no 85% rule of thumb. It sounds like you should review article 220, section 210.19(A)(1) and the definition of continuous loads in article 100.

Fancy controllers don't like the noise generated by motors and it's better to keep them on different circuits, even though that by no means keeps the noise off of the controller, it helps some. "General purpose" circuits are allowed to mix lighting with all kinds of other loads. These systems would probably prefer to have circuits used exclusively for lighting.

 

[arjo_reich]

Re: Kitchen & Bath Luminary Circuits ...

Originally posted by physis:
There is no 85% rule of thumb. It sounds like you should review article 220, section 210.19(A)(1) and the definition of continuous loads in article 100.

Thank you,

You are correct that there is no 85% rule of thumb and I did review (again) the various articles you posted.

Let me ask another question though. When you are wiring a bedroom how do you estimate the typical loads for each receptacle being placed on the circuit?

Without knowing their specific use, I assumed that 180-240 watts (1.5 - 2.0 amps) per receptacle would be a realistic metric.

 

[physis]

Re: Kitchen & Bath Luminary Circuits ...

I did review (again)

Get used to it.
I'm always reviewing this stuff.

When you are wiring a bedroom how do you estimate the typical loads for each receptacle being placed on the circuit?

I don't estimate loads per receptacle for bedrooms. 220.3(A) and 220.3(B)(10) gives you the VA for general purpose lighting and receptacle loads. It's 3 X "square footage". Divide VA by 120 to get the the current you'll need. 210.11(B) says to evenly distribute those loads at the panel.

Aside from that if there's a particular load that should be dealt with diffently then I'll address that.

 

[arjo_reich]

Re: Kitchen & Bath Luminary Circuits ...

Originally posted by physis:
I don't estimate loads per receptacle for bedrooms. 220.3(A) and 220.3(B)(10) gives you the VA for general purpose lighting and receptacle loads. It's 3 X "square footage". Divide VA by 120 to get the the current you'll need. 210.11(B) says to evenly distribute those loads at the panel.

Aside from that if there's a particular load that should be dealt with diffently then I'll address that.

Maybe it is becuase the bedrooms have to be on AFCI circuits and because I have mapped out all my lighting to be on "luminary only " circuits that I have overcomplicated the issue.



Because the lighting is always on it's own circuit, I've come up with wiring plans to distribute the loads evenly, yet economically accross the panel.

I know I've over-engineered the wiring plan for the house but I'm trying to solidly "future-proof" the wiring system for future improvements and additions to the home.

 

[George Stolz]

Re: Kitchen & Bath Luminary Circuits ...

Originally posted by arjo_reich:
I know I've over-engineered the wiring plan for the house but I'm trying to solidly "future-proof" the wiring system for future improvements and additions to the home.

Good luck. The future is hard to guess at.

What kind of automation system do you have in mind? Not to say that I've dealt with any, but there are wildly different techniques and systems for things, depending on what you have in mind.

If it causes the electrician to jump through hoops for it, it must be expensive.

 

[arjo_reich]

Re: Kitchen & Bath Luminary Circuits ...

Originally posted by georgestolz:
What kind of automation system do you have in mind? Not to say that I've dealt with any, but there are wildly different techniques and systems for things, depending on what you have in mind.

If it causes the electrician to jump through hoops for it, it must be expensive.

Actually, the "perfect world" for most automation systems is to have all controlled devices not on the same circuits as anything that could produce RF interference...and because the most commonly controlled devices are luminaries, this is where it most often applies.

Now, that being said, a number of manufacturers sell "power cleaners" that will filter out such noise in the line but those can become increasingly expensive as your system grows.

You can forego all of this heartache by using controller devices that do not communicate over the 120v lines and use their own independent signalling cables - almost always Cat 5e - but those are the most high-end systems and usually start in the upper 15,000's.

...
For me, I haven't decided but since the most affordable systems are the inline modules (X10, On-Q, HAI, etc.) I'm basically future-proofing.

Besides, if you think about it, as long as you don't put an entire floor's worth of lighting on the same circuit, doesn't it just seem "better in the long run" to have these types of isolation? Although, I suppose there is something to be said for room by room wiring as well.

 

[physis]

Re: Kitchen & Bath Luminary Circuits ...

Actually, the "perfect world" for most automation systems is to have all controlled devices not on the same circuits as anything that could produce RF interference...and because the most commonly controlled devices are luminaries, this is where it most often applies.

There has to be a mistake in your interpretation of the manufacturers literature.

These systems will simply have to work in a real environment that actually exists. Anything so delicate as to require it's own circuit for each load has two problems.

1] Dedicated circuits do not "cleans" noise from the system. They reduce it "somewhat", at best, whatever amount that might be.

2] Something that does have that kind of requirement might well be so sensitive as to be unable to operate correctly in way too many environments. The walls will be more or less permanent.

I don't have a lot of experience with these systems but I think I would stay away from any thing that either uses RF or can't tolerate it.

You should definitely look for recommendations from sources that are not salesmen.