arc-fault & generators

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wireman3736

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Vermont/Mass.
Just a thought, Should we be required to provide Arc-Fault protection for bed rooms in new construction if a reliance type transfer switching panel is installed also.
 
wireman3736 said:
Just a thought, Should we be required to provide Arc-Fault protection for bed rooms in new construction if a reliance type transfer switching panel is installed also.

We are required to, it is not a choice.

It is required if your area has not modified the NECs 210.12
 
I may not have asked the question correctly, When you install for instance an 8 circuit reliance transfer panel next to the main panel, connections are made within the main panel, under normal conditions (line) the circuits would be protected by the installed arc-fault breaker but when switched to (generator) power the arc-fault breaker by design of the transfer panel would be disconnected and power would be supplied to the circuit by the generator, now these circuits would be supplied by a non arc- fault protected source. I have installed many of these transfer panels to run off of a 5kva - 7.5kva generator for emergency use and it's common practice in my area. I think this would violate the nec but I have never heard of an inspector turning down this installation as a violation, has anyone else?
 
You explained it fine.

210.12 requires Arc Fault protection of the entire circuit supplying a bedroom.

The source of the circuit is not relevant.

Utility, generator, photo-voltaic, battery stack with inverter....whatever the source does not change the basic requirement of 210.12.

210.12 Arc-Fault Circuit-Interrupter Protection.
(A) Definition. An arc-fault circuit interrupter is a device intended to provide protection from the effects of arc faults by recognizing characteristics unique to arcing and by functioning to de-energize the circuit when an arc fault is detected.

(B) Dwelling Unit Bedrooms. All branch circuits that supply 125-volt, single-phase, 15- and 20-ampere outlets installed in dwelling unit bedrooms shall be protected by an arc-fault circuit interrupter listed to provide protection of the entire branch circuit.
 
I agree with Bob.

This is one reason circuit lay-out is important.
A small generator like that would do best to serve critical circuits such as frig, freezer, sump pump, stairway lighting, possibly a well pump, and so on.
Bedroom circuits would be 'luxury' type circuits for a small system like that, IMO.

If you have a customer that wants to have bedroom circuits served by the generator back-up, you might think about using a loadcenter that you can install AFCI breakers.
Cutler Hammer has a small panel that has a fully automatic transfer switch built into it.
CH and others have manual transfer panels that you can install AFCI breakers.

Inspectors who are not catching this violation, might not realize it.
Or, there are people installing the systems without getting an inspection at all.

I should ad that I think the AFCI's should only be required in the generator panel if they were originally required to be installed on the bedroom circuits.
Meaning, if the house was wired before the AFCI requirement, I don't think you would have to add AFCI protection to those circuits just because you're adding a generator system.
 
I agree with both of you and feel it is required per nec,, I was just looking for differing opinions to see if this is someting that was being overlooked by inspectors because I have never heard of an installation like this being turned down, the bedrooms would be a luxury to have on a generator, in vermont it effects alot more then just the bedroom, vermont required arc-fault protection a year before the nec required it, they went one step further and require it in every dwelling living area so family rms, living rms, dinning rms, etc require it. I would be interested in hearing if anyone has ever had an installation turned down because of this.
 
I think it was a little 'pre mature' for Vermont to require something like this when these breakers still havent been tested in the field.

The problem i see is that over in my area, they are finding un forseen nuisance tripping with these breakers. I know it looked good on paper, but in real world scenerios they are a problem.

Ive heard for some reason they act funny with some flourescent fixtures, or other style lights and certain bathroom and kitchen motors. Have to rewire some circuits because of this.
 
The way I understand it the arc-faults were on the market and in the field at the time Vt started requiring it they just weren't mandated before then, though I agree the field testing wasn't there yet as it also wasn't when the nec started requiring it.
 
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