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Posted By: tichetown Arch fault - 05/01/04 02:55 AM
Need some advice. I've got bedroom outlets that are wired using 14/3 romex. When I replaced the regular two pole breaker with a 2-pole arch fault,the circuit fed by the red wire trips the arch fault. When I dissconnet the branch circuit from the homerun, breaker holds. Both circuits have lights and outlets combined. This is my first dealing with arch fault. I want to know if there are certain devices that cannot be protected by an arch fault breaker. Any advice would be appriciated. Thanks
Posted By: Ryan_J Re: Arch fault - 05/01/04 03:13 AM
AFCI's, like GFCI's, don't get along well with multiwire circuits. You need another nuetral.
Posted By: tichetown Re: Arch fault - 05/01/04 03:31 AM
Do I need a second neutral parallel to the 14/3 homerun?
Posted By: caselec Re: Arch fault - 05/01/04 04:42 AM
Oops……I miss read your first post that you were using a 2-pole AFCI.


[This message has been edited by caselec (edited 05-01-2004).]
Posted By: samster Re: Arch fault - 05/01/04 04:58 AM
Are you positive you have the two hots that share the grounded conductor? Or if anywhere else in the home you have the grounded conductor of more than one cir (not your 14/3 cir but a differnt one), in say a two gang switch box and they are all tied together it would trip your two pole AFCI.

[This message has been edited by samster (edited 05-01-2004).]
Posted By: tichetown Re: Arch fault - 05/01/04 05:09 AM
Do you mean neutrals, when you said grounds? That might be my problem.
Posted By: caselec Re: Arch fault - 05/01/04 05:40 AM
Did you connect the neutral from the 14-3 to the AFCI or is it still connected to the neutral buss in the panel? If it is connected to the breaker you probably have a ground fault on the neutral somewhere in the circuit or another circuit is sharing one of your circuit conductors. Disconnect all 3 of your circuit wires in the panel and check continuity between each wire and ground. DO THIS WITH ALL POWER TURNED OFF NOT JUST YOUR CIRCUIT! If any wire shows continuity to ground you have a problem and need to start searching.

Curt
Posted By: Lostazhell Re: Arch fault - 05/01/04 06:50 AM
Most common problem I've come across when retrofitting ACFI's in is that the bare ground wire is touching a neutral terminal on a receptacle someplace... You might have a bit of troubleshooting... One way to tell is to 1) unplug everything connected to the problem circuit, turn off all light fixtures. 2) install a regular breaker for the same circuit
3) disconnect the neutral from the panel, cap it off & leave the ground connected 4) restore power & use a plug in tester on the problem circuit... If it doesn't show "Open Neutral" then you have a ground & neutral in contact someplace.. Or possibly, as Samster pointed out, a box where a neutral from another circuit leading to the panel & is tied together (paralleling) back to the panel neutral bar.. (typically would be found in 2 gang switch/recept locations where the lighting & recept circuits are separate)
Hope this helps [Linked Image]

-Randy

[This message has been edited by Lostazhell (edited 05-01-2004).]
Posted By: caselec Re: Arch fault - 05/01/04 03:49 PM
Randy

Since this is a multi-wire circuit I wouldn't recommend energizing it with the neutral disconnected. Doing so could be very expensive.

Curt
Posted By: Nick Kleyn Re: Arch fault - 05/01/04 08:24 PM
Why are you installing an Arc Fault breaker. Here in Michigan we only have to install it on new installations. Are they making you do it on existing circuits? What a pain in xxx

Nick
Posted By: Lostazhell Re: Arch fault - 05/01/04 08:57 PM
Curt...
One reason I pointed out to unplug/disconnect "everything"... I should've noted for both circuits though.... my bad! [Linked Image]
Thanks for pointing that out! [Linked Image]

Now that I'm thinking about it, You could probably just leave the power off & ohm out between the ground & neutral at a recepton the problem circuit with the power off to BOTH circuits in the 14/3 & see if theirs any continuity!....

-Randy

[This message has been edited by Lostazhell (edited 05-01-2004).]
Posted By: tichetown Re: Arch fault - 05/01/04 09:34 PM
Thank you all for the advice.
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