How would you comment on the fact that almost all of the circuits in the distribution panel are utilizing 12/3 on the 110 volt circuits? I'm finishing the report right now and would love to hear from you guys about this. Thanks! David

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From the picture I can't really see what's going on. If it's all 12/3 I assume that means a bunch of shared neutrals. I personally think evaluating the circuit design is way beyond what's expected of us as HIs. If I commented at all it would be very general.

That would indicate the house was wired with multi-wire circuits.

Nothing against code in that, personally, though, I dislike multi-wire circuits and prefer to wire in paired neutral/hot (12/2).

To me, multi-wire circuits indicates 'done on the cheap' so as to save (in the case shown) those 8 single runs of #12 ... gimme a break, that is not much money to try to save.

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Jerry Peck
Construction Consultant
Ormond Beach, Florida

Dave, from that pic it looks like there was 2 220v circuits;and the rest were 120v in which I coud not read the ratings as longas those breakers do not exceed 20 amps I see no problem..

Dave on further reveiw the breaker on the right side of the panel six down appears to be double luged ,could not tell iif that was a double throw breaker if not thats a concern

Thanks for all the replies! I won't comment on it in the report then. Man you guys are fast...appreciate the help. Dave

I call out shared neutrals on a neutral bus bar due to the possibility of a backfeed situation. With the setup on this panel where each of the 12/3 wired circuits share a neutral, shouldn't their be a tie between the breakers to ensure that you turn off both circuits sharing the same neutral?

Dave,

No. Only if both circuits are connected to the same device, such as one to each half of a duplex receptacle outlet or switch. It would be a good idea, though.

On an additional note, I try to trace the multi-wire circuits to ensure that they do indeed read 240 v across the two "hot" conductors. If not, it is possible to overload the neutral. In that panel it should be fairly easy to trace the conductors. Many of the panels in my area are too tight to effectively do this.

By the way, the grounds are bundled. But you probably already knew that.

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Thanks Gunnar,
I know that a duplex outlet for the garbage disposal and the dishwasher share the neutral...is there any other outlet situation where this may occur? Maybe a switched living room outlet? Is it even worth mentioning that there COULD be a problem?
You'd be surprised how many electricians bundled the grounds up here (or maybe you wouldn't!). I call it, but it's rarely separated. Thanks again, David

The attitude seems to be "I never saw it before, it's different, therefor it must be somehow wrong." Don't blame the world for your lack of experience!

Whether or not to 'share' neutrals is a design issue, up to the discretion of the installing electrician. Regardless of voltage ... as long as all the 'hots' are fed by different legs, and the legs are of approximately the same voltage to ground, the use of shared neutrals is perfectly proper.

Can things go wrong, especially in the hands of unqualified personnel? Absolutely. That's part of the reason I prefer to avoid using them in homes. Yet, my preference is far different from being a code requirement.
Likewise, it's nice that all the hots terminate in breakers mounted next to each other - but, again, that hasn't been code.
Handle ties? Generally, IMO, a poor idea. It's really nice that ONLY the faulted circuit trip; this helps identify which circuit has a problem, and you're not shutting off the lights when a appliance served by the other leg faults. This is but one area where the 2008 NEC is causing some unhappiness.

Yes, the 2008 NEC greatly changes the way the code looks at multi-wire branch circuits. I consider that discussion to be beyond the scope of this thread.

So, why would an electrician chose to use this method? Primarily, to make room for more circuits in the conduit, and to reduce the clutter in the panel.
Limiting ourselves to Romex as the wiring method under discussion (since that is the primary residential method), running two separate 12/2's brings 6 wires into the panel - two hots, 2 neutrals, two grounds. Use 12/3, and there are now only 4 wires .... 2 hots, 1 neutral, 1 ground. This also means an easier pull (round wire vs. flat), fewer staples, less attic clutter, etc. There can be some cost savings as less wire may be used as well.

That's what I said.

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Jerry Peck
Construction Consultant
Ormond Beach, Florida

I would certainly be interested in finding out if this was the electrical contractor following the design of the home spec's or simply cutting corners.

Yes. There is a big difference in the amount of work, headache and some cost savings associated with the 12/3 use. My money is on the electrical contractor having made the change as this is not common.

Rich

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B.S., Its to save a few bucks. As an electrician, would you "design" a system that is inherently less safe to reduce clutter? No. Would you design a system that is inherently less safe to save money? Yes.

David,

Without doing a complete evaluation on all of the circuits, there is no way to determine if anything other than the dishwasher/disposal shares a receptacle outlet. So, either you have to disclaim multi-wire circuits in your report every time you run into them, or you just have to accept that tracing individual circuits goes beyond SOP of a standard home inspection. Tracing the multi-wire circuits would be for someone doing an "in-depth" inspection and that would necessarily cost more.

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Time is the best teacher; Unfortunately it kills all its students.

Well Said John

I definitely am not the one to trace circuits throughout the home on a 2-3 hour home inspection, but my question was should I warn the client of potential problems with the multi-wired circuits? I'm getting the feeling that not many of you have run into this before, however the concensus seems to be that it's not noteworthy.

Byron Lentz stated, "The attitude seems to be "I never saw it before, it's different, therefor it must be somehow wrong." Don't blame the world for your lack of experience!"

I really can't see anyone saying that in the replies and I asked the question because of the unusual installation (and yes, it is due to my lack of experience). I think a lot of people use this board for education purposes, especially when running into unusual electrical situations. Thanks to all who responded in a professional manner and were willing to educate me on the subject.

3 conductor circuits are allowed provided the breakers are on appropriate panel legs and the handles are tied together.

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What would your reporting language look like if you came across the above panel and there were no handle ties?

Personally, I have run across romex being wired as two separate cicuits with the two breakers not tied together. I call them as a safety hazard, since quite often an unsuspecting individual will turn off a breaker to work on a switch, outlet, or whatever, not knowing the wire is still hot, and may inadvertantly cut the wire. To me it's a case of common sense as opposed to relying on a code requirement, which may not be valid or adequate.

Bob,

The breaker handles do not need to be tied together unless both legs of the multi-wire circuit go to the same device strap.

I wish that were a requirements, but it is not.

It's also easy for a do-it-yourself homeowner (and we all know they work on their own homes) to 're-arrange the circuits' while adding or removing something, and that is not a good thing with multi-wire circuits as you could end up with both legs on the same phase bus, which would cause the neutral to carry *BOTH* loads (assuming loads are 'on' on both legs, potentially resulting in twice the neutral current as the circuit was designed for) instead of either *ONE* load (assuming only one load is 'on' one leg) or *THE DIFFERENCE* between both loads (assuming loads on 'on' on both legs, only the difference in their current is carried by the neutral).

Again, allowed, yes.

Usually done to save money.

Is it a reportable item?

It would not hurt to advise your client that the panel has one or more (in this case all or almost all) circuits which are multi-wire and that extreme care should be used when they are anyone else is attempting to do any work in the panel, extreme care meaning that the multi-wire circuits should not be relocated without knowing what a multi-wire circuit is and what is required of a multi-wire circuit (i.e., that a multi-wire circuit is two 120 volt circuits, wired as a single 240 volt circuit with a neutral, and with *NO* 240 volt loads allowed on that circuit).

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Jerry Peck
Construction Consultant
Ormond Beach, Florida