Arc Faults Breakers...

[Horst1]

Ok, I have a few questions... First, I put in a new CH AFCI today, this feeds a new room addition, wired in #12, 20A breaker. It leaves the panel and goes to the first of 4 outlets, leave the outlet and goes to a switch and overhead light. From one of the outlets I put a 12/2 up to a smoke, from that smoke 12" away (on the other side of the wall) I put a 12/3. The circuit holds fine, the minute you plug a smoke in it trips the AFCI. Keep in mind this is dedicated, the wire all exposed, new and in great shape and the AFCI holds just fine until you put a smoke in. The AFCI holds with all sorts of plugged in equipment, lamps, etc. We changed the AFCI, put in 2 different brands of smokes... All the obvious. This one has me scratching the old head...

OK, #2 - I was talking to an inspector and he said that the 2005 edition of the code sunsets on Jan 1, 2008 in regards to AFCI protection. He says since the code "sunsets" on this date and no manufacturers make the new AFCI's that they will no longer be required - by code - but they will still enforce the 2005... Hmmmmm. I believe I read this in the Forums as well, anyone have any additional thoght on this?

As always, Thanks in advance -

 

[Dennis Alwon]

I have never had a problem with the smokes on an arc fault circuit. I would venture a guess that something is not wired correctly between the two smokes ( I assumed that's why you used 12/3) or the wire is shorted somehow.

I am not sure if an arc fault will trip if the neutral and ground are touching unless there is a load. Anyone know???

 

[Horst1]

wiring...

wiring...

The smokes require a 12/3 between them in order for the alarm circuit to work. The fire code requires a smoke in the bedroom and outside the bedroom (this new addition is a bedroom) that is why there is 2.

 

[Dennis Alwon]

The smokes require a 12/3 between them in order for the alarm circuit to work. The fire code requires a smoke in the bedroom and outside the bedroom (this new addition is a bedroom) that is why there is 2.

I assumed the 12/3 went to another smoke but you didn't state that in your post. Again there must be an issue with the wire. I would disconnect the 12/3 and see if you have the same issue when you plug the first smoke in. If it is fine that tells you there is a problem in the wire or the connection of the 12/3.

 

[cschmid]

try the smoke with the interlocks disconected..let me know I am curious..

 

[Horst1]

Ok, let me clarify...

Ok, let me clarify...

I have been at this electrical work for 28 years... I personally went through the entire circuit (room is 10 x 10) and the AFCI holds fine with the smokes disconnected, I have tried disconnecting the red on the 12/3, different brands of smokes, etc. I have went as far as putting a smoke directly onto the AFCI and it tripped! The problem is definitely with the AFCI. I guess what I was wondering is if anyone has ever had an issue with the Cutler Hammer brand of AFCI's. We don't usually use this brand. I'm thinking I got a bad batch. I have called bothmanufacturer of smokes and Eaton - waiting on Eaton Tech support to call back. The smoke tech support had problems understanding anything about anything... I posted this out of frustration, when my guys said this was what was happening I assumed they had missed something.... Well, the white knight riding in and making the rescue didn't work!

 

[cschmid]

okay sounds to me like you tested every thing..I am just going to see what happens let us know..

 

[Dennis Alwon]

I have used Cutler hammer but never had a problem with the arc fault. I don't normally use them but when I did there was no issue with the smokes. Curious problem.

If you take those smokes and hook to another arc fault in a different brand panel and they work then that will tell you the issue is definitely the breaker. It appers it is anyway unless you have 2 brands of smokes that are bad. I doubt that.

 

[jcole]

Everytime I had an archfault trip when energizing a load (smoke in this case) there was a egc connected intientionally or unintentionally to the grounded conductor causing the GFI portion of the archfault to trip. Could be anywhere on the circuit.

 

[wbalsam1]

Dream it up...sell the idea....manufacture it.....test it under optimum conditions.......................................get it in the code......get it in the laws......get it on the shelves......

What ever happened to "get the wrinkles out?"

 

[brantmacga]

I am not sure if an arc fault will trip if the neutral and ground are touching unless there is a load

yep i think they do.

 

[KelleyF]

yes they will trip with neutral and ground touching.

 

[augie47]

Horst1, I was not clear on one point. In disconnecting the smokes, did you disconnect the 12/3 between units or just the smoke det. themselves.
I am trying to rule out a proboem with the Romex.
(with your experience, you have probably checked each component, but I was grasping at straws and thinking maybe you just disconnected at one point)

 

[GilbeSpark]

I use CH very frequently, NEVER had an issue with smoke detectors.

It's either bad cable or bad smoke. The problem is limited to the breaker, the hot jumper to the smoke, the 12-3 jumper in between smokes, and the 2 smokes themselves. If you've swapped out the breaker and that wasn't it, and you've swapped out the smokes and that wasn't it

It's gotta be the hot feed or the 12-3 jumper or a bad breaker.

 

[don_resqcapt19]

Dennis,

I am not sure if an arc fault will trip if the neutral and ground are touching unless there is a load. Anyone know???

The AFCI will not trip with a grounded to grounding connection unless there is load on the AFCI ciruit. The ground fault trip in the AFCIs is 30 to 50 mA and without load there will be no current to trip the AFCI.
Don

 

[cschmid]

meg the 12/3 and see if the wire insulation cracked when you pulled it..I have seen old wire crack and new wire that was too cold crack as well..with the arc fault they find them for you..you just wont know what one it is..I wonder if we are going to have to add a charge to meg every line just so we can be assured of good wire before they sheet rock..

 

[ELA]

Don't know if you might have seen this before but if not you may find it helpful:

http://ecatalog.squared.com/pubs/Ci...ircuit Interrupters (AFCI)/HOM/0760DB0204.pdf


On page 5 they suggest substituting a GFCI in place of the AFCI temporarily as a diagnostic tool. This could help determine if a neutral-ground connection exists or if it is some other issue with the AFCI itself.

 

[JohnJ0906]

Dennis,

The AFCI will not trip with a grounded to grounding connection unless there is load on the AFCI ciruit. The ground fault trip in the AFCIs is 30 to 50 mA and without load there will be no current to trip the AFCI.
Don

This is my experience.

 

[Pierre C Belarge]

Don't know if you might have seen this before but if not you may find it helpful:

http://ecatalog.squared.com/pubs/Circuit%20Protection/Miniature%20Circuit%20Breakers/Arc%20Fault%20Circuit%20Interrupters%20(AFCI)/HOM/0760DB0204.pdf


On page 5 they suggest substituting a GFCI in place of the AFCI temporarily as a diagnostic tool. This could help determine if a neutral-ground connection exists or if it is some other issue with the AFCI itself.

This is a good reference to have.Thanks for posting it!!

 

[Dennis Alwon]

Dennis,

The AFCI will not trip with a grounded to grounding connection unless there is load on the AFCI ciruit. The ground fault trip in the AFCIs is 30 to 50 mA and without load there will be no current to trip the AFCI.
Don

Thanks Don, that was my suspicion.

This does not seem to be the OP's problem since the SD trips the breaker when hooked directly to it.