I have several questions about this panel. This is from a new construction warranty inspection. First the A/C 30 amp double breaker first one up from the bottom right. I see it has white wire used for hot and know it needs to be marked, it is a 220 circuit and is using two conductor romex, white and black for hot and copper wire for ground/nuetral? Should this not be wired with 3 conductor romex? Next question, the top six breakers on the right go to various 110 circuits/outlets throughout the home. However they are wired with 3 conductor romex a black for one breaker a red for one breaker and as far as I can tell two circuits share a white nuetral and copper ground. Is this ok?
1.) it is a 220 circuit and is using two conductor romex
Answer: Really is considered a 240V Circuit actually not a 220 circuit.
2.) hot and copper wire for ground/nuetral?
Answer: No neutral is being used for this circuit…so it is just the EGC for the 240V circuit.
3.) Should this not be wired with 3 conductor romex?
Answer: Not if you are talking about a Waster Heater and loads like that that have 240V and no need for 120V to the appliance.
4.)However they are wired with 3 conductor romex a black for one breaker a red for one breaker and as far as I can tell two circuits share a white nuetral and copper ground. Is this ok?
Answer: These are more than not a Multiwire Circuit which a shared grounded conductor. Is it ok and legal yes, is it a potential problem for the home owner…YES, it can be if someone removes the Grounded conductor to those circuits…this is a prime example of a potential problem for someone who may mess with the grounded/grounding bar and accidentally removeing a shared Neutral and WHAMO…120V circuits now have 240V at them .
Also it looks like in one of the pictures you have a 14 AWG on a 20A breaker…just can’t tell good enough from the image.
Now…based on what I can see…if the Red and Black are on 40A breakers and so on…this is typical but I can’t see them very well…if you are talking about 14 AWG and 12 AWG circuits on those breakers then # 4 above will apply…if they are # 8 AWG and larger probably just a 240V circuit…but they should be on COMMON trip breakers.
Now I am on my pocket pc doing this so I can’t see the images well but IF based on what you say in question # 4 I would make the client aware of this fact…but it is not against the NEC…but it is important that everyone know WHAT could happen if they remove that common neutral.
If I missed something sorry…I can’t see the images real well and will look it over when back in the office.
Thanks Paul, you were just the man I was waiting to hear from.
All the conductors on the 20 amp breakers are 12 AWG
3) So should the white wire on the 240 circuit be marked as hot?
4) The red and black conductors are 12 AWG on 20 amp breakers it appears to be a multiwire circuit that you described.
No, each bedroom doesn’t need its own AFCI but all outlets in the bedrooms need to be protected by AFCI.
I was just wondering if it’s a 6 bedroom home, and the bedrooms are supplied by two breakers. I’ve heard of crooked builders(not I didn’t say electricians) that add an addition 500 sq and put it all on 1 - 15 amp breaker.
So those 12/3 Circuits are marked on the ledger as normal circuits then yes they are multiwire shared neutral circuits and somewhere in the report simply make a note of them so as to make sure the future homeowner is clear of what could happen if they go playin in the panel later.
Re-identification of the white wire as a ungrounded conductor has actually been around since the 1999 NEC so yes as Tom stated it should be re-identified and with all the potential for the shared neutrals to be screwed up in that panel.....you are just covering your butt.
Now again nothing illegal about the Multiwire circuits…but they could be problematic so I am only suggesting it in a caution statement to help educate your client…and to be a nice guy in your clients eyes.
Now be careful those 20A multiwire circuits are not really multiwire circuits and so on…maybe they have a sump pump or something that gets 240V and so on and just happen to run 12/3…so lets not guess here…if you feel sure they are multiwire circuits as I have described then do as I said.
Anyway…sounds like you are RIGHT on top of it and doing a great job.