Smoke Detectors

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scnkapc

scnkapc

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Is it against NEC to piggy back a arc fault circuit from one bedroom to another?
Example: The smoke detector is supplied from the master bedroom. It is then interconnected with several other smoke detectors. At the last smoke in bedroom 3 they split from the smoke and fed the bedroom. So the master and bed 3 are on the same arc fault breaker. How can this be legal?
 
Re: Smoke Detectors

The only rule is that the entire circuit that feeds any outlet in any bedroom must have AFCI protection. There is no rule that says each bedroom must be on its own circuit. There is no rule that says you can't put non-bedroom outlets on the same circuit either.
 
Re: Smoke Detectors

I know of atleast 1 ec that does this and its a great idea.No violation to be found.And if he wanted to he could do all 3 bedrooms from this 1 afci circuit
 
Re: Smoke Detectors

The thought has crossed my mind on plenty of occasions, that there probably are some of us who now load up bedroom circuits alot more than we did in the past, and save ourselves the extra 40 bucks of the second afci breaker. I am myself guilty of this more than once. I almost never had more than 10 or 11 receptacle outlets on a 20 amp bedroom circuit before afci rules came into play. Some times much less. Now I have put even as many as 16, if I forgot to add for afci's when preparing my bid.
 
Re: Smoke Detectors

I have for years put master on own and shared a circuit with 2 and 3.But now with cost of breakers and wire and GC'S that only see the bottom price you might need to put all on 1 circuit.Run it in 12-2 with 20 amp breaker and you likely will be ok
 
Re: Smoke Detectors

I find it strange that so many people that have passed a test and worked in the field for years still don?t have a clue as to the proper way to load dwelling circuits.

I know that there some electricians that have convinced their selves that a 20 amp circuit is so much better than a 15 amp circuit and I have no problem with their way of thinking. What I do have a hard time understanding is that no one knows the proper way to load the circuit. It is in the book.

In the 2005 cycle 220.12 tells us to use 3 volt-amperes per square foot. Now let?s use this to load the circuit.

15 amperes times 120 volts gives us 1800 volt-amperes. Divide these 1800 volt-amperes by 3 watts per square foot and it will give you 600 square feet of space that can be wired with this circuit.

Should for some off the wall reason I use a 20 amp circuit it could be loaded to 800 square feet of space.

Care should be taken when a homeowner loads a room down with a bunch of lights such as can lights. But for the average run of the mill house without a bunch of lights this will be all that is needed for a compliant and workable system.
 
Re: Smoke Detectors

I believe 210.11(B) needs to be considered in this discussion. If one AFCI protected branch circuit serves a significantly greater building area than other general purpose circuits, this would be IMO, a violation of 210.11(B).
 
Re: Smoke Detectors

Originally posted by jwelectric: In the 2005 cycle 220.12 tells us to use 3 volt-amperes per square foot. Now let?s use this to load the circuit.
Click to expand...
That's a reasonable approach. But I am not sold on its being a requirement. Article 220 tells us how much load we need to include. But it does not tell us how to design our branch circuits. If I were to choose to load a 15 amp lighting circuit to 1800 watts (let's not get into that "continuous load" thing right now), but spread that lighting load out over 900 or even more square feet, that would not be an NEC violation.
 
Re: Smoke Detectors

Another way to do it is by determining how many general purpose branch circuits are required and dividing the square footage of the house equally.

For example:

2,400 sq ft home x 3 = 7,200 / 120 / 15 = 4

2,400 sq ft / 4 circuits = 600 sq ft per circuit.

For a bigger home:

6,000 sq ft home x 3 = 18,000 / 120 / 15 = 10

6,000 sq ft / 10 circuits = 600 sq ft per circuit.
 
Re: Smoke Detectors

600 sq feet could be easily 5 small bedrooms at 120 sq ft each.Please tell me none of you would do this on 1 15 amp circuit.I thought the 3 watts per sq ft was only for sizing the service.Did i miss something ? :confused:
 
Re: Smoke Detectors

Originally posted by jimwalker:
600 sq feet could be easily 5 small bedrooms at 120 sq ft each.Please tell me none of you would do this on 1 15 amp circuit.I thought the 3 watts per sq ft was only for sizing the service.Did i miss something ? :confused:
Click to expand...
ARTICLE 220 Branch-Circuit , Feeder, and Service Calculations
 
Re: Smoke Detectors

Mike ,Bryan and the others just look at what 600 Sq ft encompasses a 10 x 12 br is only 120 sq ft.So easily we could do an entire side of a home with 1 circuit .I`m saying 3 brs a wall in family and a hall bath lights on that circuit,even add the entry area to get to 600 sq ft.
Now this is what we are allowed to do ;) The better tradesman does it as if they were doing their own home.Key word (tradesman)Mostly a group of mid 20 year old people that have 2,3 maybe 4 years under their belt and have learned to rough in.Troubleshoot whats that ;) To ask them what they do for a living they sprout out with a robbins red chest I`M AN ELECTRICIAN.Ok so whats the take up on 1 in emt,or how do you calculate a service.Dumbfounded like a deer in the headlights.They can`t answer simple 1 year guys questions but they call themselves a tradesman.Installer yes ,tradesman no. ;) Another 5 years at least for a masters to be qualified.Now 3 years and I`m an electrician :roll:
 
Re: Smoke Detectors

Allen by loooking at some of your other posts I can tell you are an oldtimer. same as the first electrician I came up under. I do not see the sense in you making such a general degrading comment about people in my age bracket. Yes some are pure idiots. Such as the guy who is supposed to be leadman on my truck. Why because hes a 20 yearold know it all electrician. But he cant even operate a meter. Troubleshooting he runs from. However there are others like myself that know a 8 inch deduct on a 1 inch conduit. Or run to a ts call because we find it fun. However I am not a good enough conduit runner in my own eyes to call myself a full fledged electrician. So I would greatly appreciate it if you could restrain from making these bs statements. I have my own complaints about oldtimers but I generally keep them to myself in this forum
 
Re: Smoke Detectors

Southernboys, there are many helpers with 20, 30, 40 years in this trade, you will recognize them by their words and actions.

On the other hand, there are masters in their twenties with 8, 10, 15 years in this trade, you will recognize them by their words and actions. :)


Roger

[ December 09, 2005, 07:25 PM: Message edited by: roger ]
 
Re: Smoke Detectors

I try not to judge others by age,sex,or race.Simply watch them for a few hours or days.Then rate them.As for a crew leader that cant trouble shoot ,that's easy just act as stupid as he is and the company will get him out of the drivers seat.If you bail him out he will report it as he found and fixed the problems.
 
Re: Smoke Detectors

Jim I agree but its one of em small family owned and friend ran companys. so thats not likely. What I have been tempted to do is wire a gfi Backwards and see if he catches it. To give you guys an idea about him. house today noone marked arcfault circuits. I hooked all wires up to 15a breakers. Told him what I did. Came time to check house out. He wanted to put panel cover on. Had to tell him 3 times not to put cover on due to arcfaults not being known. Finally had to take cover from him so he wouldnt put it on. His reasoning for putting cover on He didnt want to bend over to label circuits. So youd rather put a cover on just to take it back down?
 
Re: Smoke Detectors

Sounds like this is company you would be best of not working for.I have worked for a few that only took a week or 2 to figure out i made wrong choice.But there was 1 that only took 3 days.He yelled and screamed at everyone.First day i figured he was just having a bad day.On 3rd day i asked my partner and he said this was normal.On 4th morning i called and told him i quit.Funny part was he had told me on the phone that guys keep leaving him.Wonder why ? He also hired relatives.I refuse to get yelled at because his niece was stupid and starting cutting up a diningroom ceiling looking for the smoke detector. Best way to deal with nepotism is to leave.But wait till you get the x mas bonus and holiday pay :D
 
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Hey S Boy there are also many good quality younger guys that i know and many that I have stuffed under my old tired wing ;)
 
Re: Smoke Detectors

Allen, notice I wasn't talking about age, but time in the trade. 20,30, or 40 years experience doesn't make an electrician as Southernboy knows.

Many of these old timers can do a task, but have no idea of why it must be done a certain way, this is due to thier lack of basic theory or simple math.

They may have some strong points and can actually be promoted for these points, but this still doesn't make them electricians.

Roger
 
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