quote:

---

> Poking around in my residential main breaker panel recently, I noticed
> what seemed to be a shortage of neutral connections. While making some
> wiring changes, I think I stumbled on the why. It seems that the
> installer wired a few outlets on L1, and a few on L2, and shared a
> neutral between them. To her credit (permit attributes the work to
> "Wonder Woman", 1976) red wire was used at least to the first (only, I
> think) outlet on L1, and black to the outlets on L2.
>
> Now, it seems at least one reason this is a bad idea is that if someone
> (like me) not in the know started moving breakers around (which I did:
> time out for mental note to check on this) you could quite easily end up
> putting twice as much current down the neutral as it was designed for.
>
> Another would be that if the neutral gets disconnected somewhere it
> might get slapped around from L1 to L2 or somewhere in between depending
> on the loads: which might result in overvoltage in addition to the usual
> hazards asscoiated with an open neutral.
>
> Is this kind of thing even permitted? If so, is it generally considered
> poor practice? How poor? Just curious. I'd never do it. I'll be fixing
> it, "broken" or not.
>
> -Andrew

quote:

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> Andrew Thomas wrote:
>
>
>
> Andrew
> I'm not going to be gentle about this! If you are not willing or able
> to invest the time needed to learn about the care and feeding of Edison
> circuits then you have no business doing any electrical work. I reject
> the idea that the entire craft should be dumbed down to the Harry
> Homeowner level. There is always a chance of another circuit being in a
> box. If you don't know how to do safety testing before starting work
> then don't remove the cover of the box!
> --
> Tom H

quote:

---

> Poking around in my residential main breaker panel recently, I noticed
> what seemed to be a shortage of neutral connections. While making some
> wiring changes, I think I stumbled on the why. It seems that the installer
> wired a few outlets on L1, and a few on L2, and shared a neutral between
> them. To her credit (permit attributes the work to "Wonder Woman", 1976)
> red wire was used at least to the first (only, I think) outlet on L1, and
> black to the outlets on L2.
>
> Now, it seems at least one reason this is a bad idea is that if someone
> (like me) not in the know started moving breakers around (which I did:
> time out for mental note to check on this) you could quite easily end up
> putting twice as much current down the neutral as it was designed for.
>
> Another would be that if the neutral gets disconnected somewhere it might
> get slapped around from L1 to L2 or somewhere in between depending on the
> loads: which might result in overvoltage in addition to the usual hazards
> asscoiated with an open neutral.
>
> Is this kind of thing even permitted? If so, is it generally considered
> poor practice? How poor? Just curious. I'd never do it. I'll be fixing it,
> "broken" or not.
>
> -Andrew

quote:

---

> HorneTD wrote:
>
>
>
> Uh, dude, a lot of that was tongue in cheek. This kind of attitude is
> such a broken record I don't know why anyone bothers. If you don't know
> the answers and/or aren't willing to share don't waste the bandwidth. I
> don't like having to waste bandwidth with the disclaimer that your type
> shouldn't bother to respond in every single post. Sadly it seems necessary.
>
> In fact I spent many years as an electrician and have wired many homes,
> and have seen so much shoddy and just plain wrong work by "qualified
> professionals" that you should be ashamed of yourself for promoting this
> black and white attitude in the first place. Ask any inspector and he
> will tell you that 9 out of 10 of the jobs he remembers as the best he
> has ever seen have been by "unqualified" homeowners motivated primarily
> by pride in workmanship, safety of their family, and the long-term
> investment in their property rather than the quick buck. And don't try
> to tell me that by far the majority of electricians aren't primarily
> motivated by the quick buck, quick being the operative word: 'cause I
> been there, man, I've seen it all and enough of it to call you a liar,
> straight up.
>
> Double shame on you, you robotic parrot.
>
> -Andrew

quote:

---

> On Sun, 01 May 2005 04:57:36 GMT Andrew Thomas <cornheadorama@hotmail.com> wrote:
>
> | Poking around in my residential main breaker panel recently, I noticed
> | what seemed to be a shortage of neutral connections. While making some
> | wiring changes, I think I stumbled on the why. It seems that the
> | installer wired a few outlets on L1, and a few on L2, and shared a
> | neutral between them. To her credit (permit attributes the work to
> | "Wonder Woman", 1976) red wire was used at least to the first (only, I
> | think) outlet on L1, and black to the outlets on L2.
> |
> | Now, it seems at least one reason this is a bad idea is that if someone
> | (like me) not in the know started moving breakers around (which I did:
> | time out for mental note to check on this) you could quite easily end up
> | putting twice as much current down the neutral as it was designed for.
> |
> | Another would be that if the neutral gets disconnected somewhere it
> | might get slapped around from L1 to L2 or somewhere in between depending
> | on the loads: which might result in overvoltage in addition to the usual
> | hazards asscoiated with an open neutral.
>
> The overvoltage is the worst of the open neutral issues, I think. And one
> big trouble is, when things start acting funny due to an open neutral,
> the worst reaction is to shut off the power at each device, and usually
> first on the ones with more voltage, making things even worse for the rest
> that have overvoltage. If you ever suspect an open neutral situation,
> switch off the main first.
>
>
> | Is this kind of thing even permitted? If so, is it generally considered
> | poor practice? How poor? Just curious. I'd never do it. I'll be fixing
> | it, "broken" or not.
>
> A shared neutral is permitted, acceptable, and often a good idea as long
> as it is done in the right way. I don't think the code goes so far as to
> require a double pole (240v) breaker for these circuits, but IMHO it should.
> Circuits sharing the same yoke/device do need to be under a common handle,
> and because that's always opposite phases, you'll have 240 volts L-L in that
> case (I've never seen common handle breakers that get the same phase and
> they would be dangerous to DIY-ers if they did exist because of the chance
> of them wiring them up with common neutrals).
>
> As long as a shared neutral is wired to a double pole (240 volts) breaker,
> run in a single cable (the big reason to do this so you can have twice the
> circuit capacity from the work of pulling wire once), and color coded
> correctly, it should be a safe install, and remain safe under maintenance
> of knowledgeable people in the future.
>