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Can Edison circuite (12-3) be continued as separate 12-2 regular circuits?

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blueman

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Jan 6, 2010, 6:01:16 PM1/6/10
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I have an Edison circuit with 12/3 wiring feeding a duplex outlet with
one circuit and associated outlet dedicated to a basement freezer. The
other outlet of the duplex pair is on the other leg and used for general
purpose.

Can I continue the wiring from that one leg to feed other outlets
downstream using 12/2 wiring (dropping the conductor for the dedicated
freezer outlet) or do I need to continue to feed the 12/3
wiring everywhere?

Note the outlet box with the split Edison duplex is labelled as such.

RBM

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Jan 6, 2010, 6:12:09 PM1/6/10
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"blueman" <NOS...@nospam.com> wrote in message
news:m2hbqyz...@consult.pretender...

Absolutely! The one thing that you must do with an Edison circuit, is
pigtail the neutrals, as the Nec doesn't allow their integrity to be
dependent upon a device. Once you break them into two 2 wire circuits, you
just wire them as you would any 2 wire circuit.


blueman

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Jan 8, 2010, 4:05:03 AM1/8/10
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Am I right to interpret that you only need to pigtail the neutrals while
it's still an Edison circuit (i.e., while both phases enter a box on 3
conductor cable and feed different devices in the same boxe). But that
once I am beyond the shared box and onto a regular 2-conductor circuit then I
don't need to pigtail neurtrals any more but can daisy chain through
devices again?

Or does every junction on the circuit need to have the neutrals
pigtailed rather than daisy-chained?

Also, while you are at it, are there any other code 'gotchas' that I
should be aware of with Edison circuits?

Thanks

RBM

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Jan 8, 2010, 6:56:05 AM1/8/10
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"blueman" <NOS...@nospam.com> wrote in message
news:m27hrtx...@consult.pretender...


You are correct about the neutrals. The newer Nec requires that Edison
circuits be on double pole breakers, essentially to insure that your hot
legs are on different legs of the service.


bud--

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Jan 8, 2010, 9:55:23 AM1/8/10
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The rationale was that the whole circuit is dead so you don't wind up
with a 'hot neutral' when you are working on the circuit.

--
bud--

Chip C

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Jan 8, 2010, 10:09:41 AM1/8/10
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The problem is that, as long as that freezer duplex outlet is a split
receptacle, you need to have the two hot legs on linked breakers. That
means that if anything on your new receptacles tripped its breaker,
your freezer's breaker would go out. This is not good wiring practice,
and may actually be against code, in that code often requires such
things as freezers and sump pumps to be on their own circuits, for
obvious reasons.

You should plan to quit using the other half of the outlet that's at
the freezer, in fact I'd put a simplex outlet in there. Then rewire
that outlet so it's entirely on one leg; the red leg, say. Then I'd
run all the downstream outlets off the black leg. You'd put one of
them close enough to pick up whatever you were plugging into the other
half of the freezer outlet.

Now, because you don't have both legs feeding any one "strap" (ie, any
two outlets on the same duplex device) I *think*, depending on the
exact wording of code that applies in your area, you can now unlink
the two breakers. Of course you must make sure the two hots are on
different legs of the panel, but that *really* should already the case
(check it, while you're at it). You should probably change the label
on the freezer outlet to say something like "power in this box is
controlled by two separate breakers".

Chip C
Toronto

Doug Miller

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Jan 8, 2010, 10:58:37 AM1/8/10
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>The problem is that, as long as that freezer duplex outlet is a split
>receptacle, you need to have the two hot legs on linked breakers. That
>means that if anything on your new receptacles tripped its breaker,
>your freezer's breaker would go out. This is not good wiring practice,
>and may actually be against code, in that code often requires such
>things as freezers and sump pumps to be on their own circuits, for
>obvious reasons.

You're right about it not being good practice -- but please cite an example of
Code requiring a freezer or a sump pump to be on a dedicated circuit.


>
>You should plan to quit using the other half of the outlet that's at
>the freezer, in fact I'd put a simplex outlet in there. Then rewire
>that outlet so it's entirely on one leg; the red leg, say. Then I'd
>run all the downstream outlets off the black leg. You'd put one of
>them close enough to pick up whatever you were plugging into the other
>half of the freezer outlet.

Still has the same problem with disconnecting the entire circuit...


>
>Now, because you don't have both legs feeding any one "strap" (ie, any
>two outlets on the same duplex device) I *think*, depending on the
>exact wording of code that applies in your area, you can now unlink
>the two breakers.

Nope. That was permitted under the 2005 and earlier versions of the
NEC, but it violates the 2008 NEC, and (I believe) violates the CEC going back
*many* years.

RBM

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Jan 8, 2010, 1:06:56 PM1/8/10
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"bud--" <remove....@isp.com> wrote in message
news:b7495$4b474739$cde8d532$26...@DIALUPUSA.NET...


Can't be, that actually makes common sense (lol)


blueman

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Jan 11, 2010, 4:51:08 PM1/11/10
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bud-- <remove....@isp.com> writes:

Yes - because while having them trip at the same time is a safety
feature (and a good idea). Having them on opposit legs is a safety
necessity because otherwise you run the risk of having 2x the current on
the common neutral. So a 12-3 would be carrying up to 40A. While if the
2 hots are on opposite phases, then there is actually no net currrent
flowing in the neutral when the hots are maximally loaded.

blueman

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Jan 11, 2010, 4:55:49 PM1/11/10
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Chip C <chipc...@yahoo.com> writes:
> On Jan 6, 6:01 pm, blueman <NOS...@nospam.com> wrote:
>> I have an Edison circuit with 12/3 wiring feeding a duplex outlet with
>> one circuit and associated outlet dedicated to a basement freezer. The
>> other outlet of the duplex pair is on the other leg and used for general
>> purpose.
>>
>> Can I continue the wiring from that one leg to feed other outlets
>> downstream using 12/2 wiring (dropping the conductor for the dedicated
>> freezer outlet) or do I need to continue to feed the 12/3
>> wiring everywhere?
>>
>> Note the outlet box with the split Edison duplex is labelled as such.
>
> The problem is that, as long as that freezer duplex outlet is a split
> receptacle, you need to have the two hot legs on linked breakers. That
> means that if anything on your new receptacles tripped its breaker,
> your freezer's breaker would go out. This is not good wiring practice,
> and may actually be against code, in that code often requires such
> things as freezers and sump pumps to be on their own circuits, for
> obvious reasons.

That is a good practical point. But luckily I don't use that other
outlet much. And since it is a basement freezer, I'm not sure the NEC
applies as it would in the kitchen. But I'm just guessing on that.
Nevertheless, I will think about your point...

> You should plan to quit using the other half of the outlet that's at
> the freezer, in fact I'd put a simplex outlet in there. Then rewire
> that outlet so it's entirely on one leg; the red leg, say. Then I'd
> run all the downstream outlets off the black leg. You'd put one of
> them close enough to pick up whatever you were plugging into the other
> half of the freezer outlet.

That is how it is wired now - with the exception that I added a bar to
tie the two halves together (which as you pointed out has some
negatives).


>
> Now, because you don't have both legs feeding any one "strap" (ie, any
> two outlets on the same duplex device) I *think*, depending on the
> exact wording of code that applies in your area, you can now unlink
> the two breakers.

I don't know myself.

> Of course you must make sure the two hots are on
> different legs of the panel, but that *really* should already the case
> (check it, while you're at it).

It is definitely that way!.

> You should probably change the label
> on the freezer outlet to say something like "power in this box is
> controlled by two separate breakers".

Already so-labelled...

bud--

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Jan 12, 2010, 12:27:21 PM1/12/10
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blueman wrote:
> Chip C <chipc...@yahoo.com> writes:
>> On Jan 6, 6:01 pm, blueman <NOS...@nospam.com> wrote:
>>> I have an Edison circuit with 12/3 wiring feeding a duplex outlet with
>>> one circuit and associated outlet dedicated to a basement freezer. The
>>> other outlet of the duplex pair is on the other leg and used for general
>>> purpose.
>>>
>>> Can I continue the wiring from that one leg to feed other outlets
>>> downstream using 12/2 wiring (dropping the conductor for the dedicated
>>> freezer outlet) or do I need to continue to feed the 12/3
>>> wiring everywhere?
>>>
>>> Note the outlet box with the split Edison duplex is labelled as such.
>> The problem is that, as long as that freezer duplex outlet is a split
>> receptacle, you need to have the two hot legs on linked breakers. That
>> means that if anything on your new receptacles tripped its breaker,
>> your freezer's breaker would go out.

If there are 2 separate breakers with a handle tie, tripping one breaker
may or may not trip the other breaker. (With a multipole breaker all
poles will open.)

>> This is not good wiring practice,
>> and may actually be against code, in that code often requires such
>> things as freezers and sump pumps to be on their own circuits, for
>> obvious reasons.

As Doug said, the NEC has no such requirement.

> That is a good practical point. But luckily I don't use that other
> outlet much. And since it is a basement freezer, I'm not sure the NEC
> applies as it would in the kitchen. But I'm just guessing on that.
> Nevertheless, I will think about your point...

The same NEC requirements apply.

>> You should plan to quit using the other half of the outlet that's at
>> the freezer, in fact I'd put a simplex outlet in there. Then rewire
>> that outlet so it's entirely on one leg; the red leg, say. Then I'd
>> run all the downstream outlets off the black leg. You'd put one of
>> them close enough to pick up whatever you were plugging into the other
>> half of the freezer outlet.
>
> That is how it is wired now - with the exception that I added a bar to
> tie the two halves together (which as you pointed out has some
> negatives).
>> Now, because you don't have both legs feeding any one "strap" (ie, any
>> two outlets on the same duplex device) I *think*, depending on the
>> exact wording of code that applies in your area, you can now unlink
>> the two breakers.
>
> I don't know myself.

The requirement to have a "simultaneous disconnect" for an Edison
circuit starts in the 2008 NEC. Before that, if 2 circuits were
connected to the same duplex outlet you needed a simultaneous disconnect
- probably starting with the 2002 NEC. Before the 2002 NEC you didn't
need a simultaneous disconnect. Whether you need a handle tie (or
multipole breaker) depends on what code was in effect when
wiring/changes were done.

If the receptacle was not split-wired and was there before the 2008 NEC
was in effect you don't need a simultaneous disconnect. If you extend
the circuit you probably do.

--
bud--

bud--

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Jan 12, 2010, 12:36:36 PM1/12/10
to

The change was not based on having the wires on different legs. As I
said, it was based on totally disconnecting the circuit to avoid "hot
neutrals". It is one of the changes based on a dead body - in this case
an electrician. Dead bodies are effective in promoting code changes. One
of the change proposals came from OSHA, which probably also helped.

Maybe we should just make all circuits like UK construction sites, which
I believe are 120V with the transformer center tap earthed. There are 2
hot wires both 60 volts to ground.

--
bud--

blueman

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Jan 16, 2010, 6:41:44 PM1/16/10
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bud-- <remove....@isp.com> writes:
> If there are 2 separate breakers with a handle tie, tripping one
> breaker may or may not trip the other breaker. (With a multipole
> breaker all poles will open.)
Please bear with me here... I thought the purpose of the "handle tie"
was to ensure that tripping one pole tripped the other. Of course, there
is always the possibility that the "spring" won't be strong enough to
trip both but I thought that at least "in theory", tripping one should
trip the other. If not, then what is the purpose of the "handle tie"
other than perhaps to serve as a glorified visual notice to anybody
opening the panel that the circuits are connected.

> The requirement to have a "simultaneous disconnect" for an Edison
> circuit starts in the 2008 NEC. Before that, if 2 circuits were
> connected to the same duplex outlet you needed a simultaneous
> disconnect - probably starting with the 2002 NEC. Before the 2002 NEC
> you didn't need a simultaneous disconnect. Whether you need a handle
> tie (or multipole breaker) depends on what code was in effect when
> wiring/changes were done.

I'm a little confused.
Per NEC, does a handle-tie count as a "simultaneous disconnect" or
does only a multipole breaker count?
If not, when did a handle-tie stop being code-approved for Edison
circuits?

In other words, are you saying that a multipole breaker is a code
requirement or just that in practice a multipole breaker is likely to be
more effective and a good idea versus a handle-tie?

Bob

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Jan 16, 2010, 7:21:17 PM1/16/10
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On 1/16/2010 15:41, blueman wrote:

> Please bear with me here... I thought the purpose of the "handle tie"
> was to ensure that tripping one pole tripped the other. Of course, there
> is always the possibility that the "spring" won't be strong enough to
> trip both but I thought that at least "in theory", tripping one should

> trip the other. If not, then what is the purpose of the "handle tie"...

There's an internal mechanism to cause a common trip, even when the tie
between the handles is broken. I discovered this after I tried removing
the tie to convert the double pole breaker into two singles. I was able
to shut off one side at a time, but when one side tripped, both sides
went tint trip mode.

bud--

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Jan 17, 2010, 11:17:57 AM1/17/10
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blueman wrote:
> bud-- <remove....@isp.com> writes:
>> If there are 2 separate breakers with a handle tie, tripping one
>> breaker may or may not trip the other breaker. (With a multipole
>> breaker all poles will open.)
>
> Please bear with me here... I thought the purpose of the "handle tie"
> was to ensure that tripping one pole tripped the other.

The purpose of a handle tie for separate breakers is to guarantee both
breakers are "simultaneously disconnected" (the code requirement) so the
entire Edison circuit is dead for service work.

> Of course, there
> is always the possibility that the "spring" won't be strong enough to
> trip both but I thought that at least "in theory", tripping one should
> trip the other.

I have fairly often turned a breaker on when there is a short. The
breaker trips while my thumb is still turning the breaker on - the
handle is on and the breaker is off. This is a necessary feature and is
called "trip free". Also prevents someone from 'holding' a breaker on
when it should be tripped.

When the breaker trips like that I don't feel any particular pressure on
my thumb. The mechanism in the breaker has to open the breaker. It does
not have to trip a breaker that has been ganged with a handle tie (but
some breakers might).

If you want a common trip use a multipole breaker. The common trip, as
Bob wrote, is internal - the breaker has been designed to trip all poles.

> If not, then what is the purpose of the "handle tie"
> other than perhaps to serve as a glorified visual notice to anybody
> opening the panel that the circuits are connected.

The handle tie is to "simultaneously disconnect" (the code requirement)
all of the circuit so the entire circuit is dead for service work. That
is clearly why the "simultaneous disconnect"requirement, which
previously applied to Edison circuits that supplied a split wired
receptacle, was extended to the entire Edison circuit in the 2008 NEC.
(It is clear if you read code change proposals and action of the code
panel.)

>
>> The requirement to have a "simultaneous disconnect" for an Edison
>> circuit starts in the 2008 NEC. Before that, if 2 circuits were
>> connected to the same duplex outlet you needed a simultaneous
>> disconnect - probably starting with the 2002 NEC. Before the 2002 NEC
>> you didn't need a simultaneous disconnect. Whether you need a handle
>> tie (or multipole breaker) depends on what code was in effect when
>> wiring/changes were done.
>
> I'm a little confused.
> Per NEC, does a handle-tie count as a "simultaneous disconnect" or
> does only a multipole breaker count?
> If not, when did a handle-tie stop being code-approved for Edison
> circuits?

Both a multipole breaker and separate breakers with a (listed) handle
tie comply with the "simultaneous disconnect" requirement in the NEC.

>
> In other words, are you saying that a multipole breaker is a code
> requirement or just that in practice a multipole breaker is likely to be
> more effective and a good idea versus a handle-tie?

A multipole breaker is only required if you want a common trip. You want
a common trip for a 220V device like a clothes dryer.

For an Edison circuit the NEC only *requires* a "simultaneous
disconnect". Use a multipole breaker if you want to.

--
bud--

blueman

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Jan 17, 2010, 6:27:48 PM1/17/10
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bud-- <remove....@isp.com> writes:

Thanks for the clarification. Very helpful...

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