Running new circuits, is 12/3 cable OK to save runs?
Mikepier
a friend of mine
1-Fridge
1- Microwave/Range hood
2-counter outlets ( as required by code I was told)
The runs from the kitchen to the panel is very long and I also have to
drill through several ceiling joists. I was thinking of running 2-12/3
cables instead of 4-12/2 cables. Is this allowed by code? I think
someone mentioned for the counter outlets is fine, but I'm not sure
about the fridge and microwave.
aemeijers
But don't you have to gang the breakers for the outlets and/or the
fridge/micro, if you wire it like that? Kinda defeats the purpose of
having separate strings, methinks. Plus, 12/3 is a lot harder to work
with, and stuff into boxes. I'm no code wizard, but IIRC, you have to
maintain both hots all the way to the end of the string, and are not
allowed to split the neutral and head 2 different directions. But I
could be wrong- somebody will be along to correct me momentarily.
I can't remember- how big does the hole through a joist have to be, to
pass multiple 12/2 feeds through it? I'd go that route if you can.
And on general principles- even if something 'odd' is code legal, or
barely so, it will confuse the poor SOB 20 years from now working on it.
Best to keep things as simple and self-evident as possible.
--
aem sends...
millinghill
> cables instead of 4-12/2 cables. Is this allowed by code? I think
> someone mentioned for the counter outlets is fine, but I'm not sure
> about the fridge and microwave.
I remeber reading that if curent to/from device is in one conduit, the
EMF will not create induction heating. But your case will because at
least one of your wires is sending in one conduit, and the return is
in the other. I'm sure the bonafide electricians out there will
clarify.
Steve Barker
If you insist on drilling less holes, you'd be better off with a couple
runs of 12/2/2. You'd have a proper neutral for every circuit that way.
You have issues sharing neutrals with GFCI outlets.
--
Steve Barker
remove the "not" from my address to email
RBM
"Mikepier" <mike...@optonline.net> wrote in message
news:06dca548-fdd0-4b7e...@h7g2000yqn.googlegroups.com...
For a kitchen, where AFCI circuits are not required it is perfectly
acceptable to do what you propose. You do have to connect them to double
pole breakers, so both circuits are opened simultaneously.
RBM
"aemeijers" <aeme...@att.net> wrote in message
news:9uidnXpE2NWjvjTR...@giganews.com...
> On 10/3/2010 8:20 PM, Mikepier wrote:
>> I have to run 4 new circuits for a kitchen I am helping to remodel for
>> a friend of mine
>>
>> 1-Fridge
>> 1- Microwave/Range hood
>> 2-counter outlets ( as required by code I was told)
>>
>> The runs from the kitchen to the panel is very long and I also have to
>> drill through several ceiling joists. I was thinking of running 2-12/3
>> cables instead of 4-12/2 cables. Is this allowed by code? I think
>> someone mentioned for the counter outlets is fine, but I'm not sure
>> about the fridge and microwave.
>
> But don't you have to gang the breakers for the outlets and/or the
> fridge/micro, if you wire it like that? Kinda defeats the purpose of
> having separate strings, methinks. Plus, 12/3 is a lot harder to work
> with, and stuff into boxes. I'm no code wizard, but IIRC, you have to
> maintain both hots all the way to the end of the string, and are not
> allowed to split the neutral and head 2 different directions. But I could
> be wrong- somebody will be along to correct me momentarily.
When it's a long run, it makes sense to use a 3 wire. You just terminate it
in a big ass box. It is a bit annoying to have to use a double pole breaker,
because you can't just shut down one circuit, but the idea is to prevent
miswired Edison circuits, which can be a fire hazard.
Mikepier
run seperate12/2's.
Now to another subject without starting a new thread: is there a
certain guidline on where to drill holes in 2X8 joists? Can I feed
2-12/2 romex's into one hole? How big of a hole can I drill?
The Henchman
"Mikepier" <mike...@optonline.net> wrote in message
news:06dca548-fdd0-4b7e...@h7g2000yqn.googlegroups.com...
Microwave/range hoods use a lot of power. Mine uses 1500 watts. Should
that have it's own neutral? We put ours on a single 14/2
RBM
A 3/4" hole at least 2" from the edge of the joist is fine for 2, 12/2
cables
George
But in this case the GFCIs don't know anything about the neutral being
shared because they are connected downstream.
Stormin Mormon
doesn't puncture the wire with a nail from above.
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"RBM" <rb...@live.com> wrote in message
news:4ca93a9b$0$7129$607e...@cv.net...
Art Todesco
run, but not how long. If it is really
long, a sub panel might be the answer to
keep voltage drop down. It might make
sense, especially if there are other
possible additions in the future.
jamesgangnc
By my count you have 3 circuits. Are 2 circuits for the counter top
required by code now?
Steve Barker
ok, go ahead and try that.
Mikepier
That is what I meant above. 2 seperate circuits for 2 counter outlets.
I was told this is code.
Steve Barker
have been for many a year.
RicodJour
Way bigger than you need for four 12/2. Some electricians drill more
and smaller holes, but I think that's primarily because they lost the
chuck key and don't want to change the bit.
http://www.qis-tx.com/images/newsletter.0605b.gif
R
Wayne Whitney
> I have to run 4 new circuits for a kitchen I am helping to remodel for
> a friend of mine
>
> 1-Fridge
> 1-Microwave/Range hood
> 2-counter outlets ( as required by code I was told)
>
> The runs from the kitchen to the panel is very long and I also have to
> drill through several ceiling joists. I was thinking of running 2-12/3
> cables instead of 4-12/2 cables. Is this allowed by code?
It is allowed, and it will give you a slightly better performing
installation than running the 4-12/2 cables. [Less voltage drop, less
use of resources (copper), marginally smaller holes in the floor
joists.] However, as you can see from the variety of responses, it is
also confusing to many people, so that may be an issue.
The only downside is that you will need to use a double pole breaker
or a handle tie with two single pole breakers on opposite phases.
Once you arrive at your destination, you can split the 12/3 into two
separate 12/2 circuits as desired. This will in fact be necessary
downstream of any GFCI receptacles.
Cheers, Wayne
Wayne Whitney
> Now to another subject without starting a new thread: is there a
> certain guidline on where to drill holes in 2X8 joists?
The best place for holes in a joist is at the neutral axis where the
joist is only stressed in bending. What this means in practice is to
stay away (maybe 2 feet?) from the bearing points (over and under wall
framing) and then to put your holes in the middle of the joist.
> Can I feed 2-12/2 romex's into one hole?
Yes, in fact if you would find it easier, you can feed all four 12/2s,
or two 12/3s, without any problem NEC-wise.
> How big of a hole can I drill?
The maximum size hole you are allowed to drill is quite a bit more
than what you will need, e.g. a 1.25" hole for 4 12/2s would be fine.
Cheers, Wayne
Wayne Whitney
> I remeber reading that if curent to/from device is in one conduit,
> the EMF will not create induction heating. But your case will
> because at least one of your wires is sending in one conduit, and
> the return is in the other. I'm sure the bonafide electricians out
> there will clarify.
Having a physical current loop will cause EMI and induction heating in
any ferrous metal encircled by the loop. However, using a 12/3 cable
for a MWBC does not create a current loop, all the conductors are
routed together in the same cable.
Cheers, Wayne
Wayne Whitney
GFCI receptacles only require a dedicated neutral downstream of the
receptacle (on the load side), you can feed them with a shared neutral
no problem.
Cheers, Wayne
Harry K
> "aemeijers" <aemeij...@att.net> wrote in message
ass because someone way back used a common nuetral on separate
circuits. White wire bit me - I traced it to a yard light that was
always on.
Harry K
bud--
In that case there should have been at least 2 hot wires in the box, one
of which remained hot when you killed the circuit you were working on.
"Hot neutrals" are the reason the 2008 NEC was changed to require listed
handle ties or multipole breakers.
--
bud--
Mikepier
soemthing.
The present stove is on a 40A circuit. I was told newer stoves require
a 60A circuit.
Which means now I have to run a new 6/3 with a ground.
How many holes or notches are you permitted to drill through one
joist? Is it better to drill several small holes , or one big hole?
RicodJour
Avoid notches whenever possible - far more problematic. Your one big
hole wouldn't be that big of a hole. If the one hole falls within the
guidelines in that link I posted, you're fine. You won't be anywhere
near the upper limit of allowable hole size, so I'm not quite sure why
you're worrying. If you want to drill more holes that's not a problem
unless you drill them to close together.
R
Steve Barker
very helpful diagram. Where it says 'no notches', does that mean no
holes also? I'm thinking no it doesn't mean that, but wasn't sure.
Steve Barker
ok, that clears that up. what i did is run 12/3 from box to box to box,
and alternated using the red and black. In this case, i have to use a
gfci at each and every box.
DD_BobK
Rico-
Thanks, a great diagram.
I remember a while ago someone posted one similar but it also spoke to
the prohibition of holes in the "bearing zone".
Something like "no holes within xx" of the end of the joist /
beam" ? Bearing zone or shear zone? I dont remember the details &
cannot find the thread or link.
cheers
Bob
Mikepier
ceiling in a living room a few times to run the wires to the panel.
Rather than cut several big holes in the sheetrock to drill through
the floor joists, I thought just "notching" the sheetrock under where
the joist is, then notchng the joist would be easier and less to patch
up.
Mikepier
went on GE's website and looked at the specs for their electric
stoves, and they all say use 40A minimum circuit. They also say to use
a 40A stove plug kit. So at least I don't have to re-run the circuit,
which would have been a PITA.
RBM
"Stormin Mormon" <cayoung61**spamblock##@hotmail.com> wrote in message
news:i8cgfq$btu$1...@news.eternal-september.org...
Wayne Whitney
> The present stove is on a 40A circuit. I was told newer stoves
> require a 60A circuit. Which means now I have to run a new 6/3 with
> a ground.
I don't know anything about electric stoves. But NM (Romex or SER)
#6 Cu has an ampacity of only 55 amps. Which means you can use a 60A
breaker on it only if the load is rated at 55A or lower. If the stove
is rated 60A, you need to use #4 Cu.
Cheers, Wayne
Wayne Whitney
> very helpful diagram. Where it says 'no notches', does that mean no
> holes also? I'm thinking no it doesn't mean that, but wasn't sure.
No notches applies to the central third of the joist. Holes are fine
there.
Cheers, Wayne
Wayne Whitney
> I remember a while ago someone posted one similar but it also spoke to
> the prohibition of holes in the "bearing zone".
>
> Something like "no holes within xx" of the end of the joist /
> beam" ? Bearing zone or shear zone? I dont remember the details &
> cannot find the thread or link.
I would think that staying a distance D (depth of member) away from
the bearing zone would be sufficient, but I would stay 2D away to be
sure.
Cheers, Wayne
Wayne Whitney
> The reason why I prefer notches is because I have to break a
> sheetrock ceiling in a living room a few times to run the wires to
> the panel.
Notching is much, much worse for the strength of the joist than
drilling a hole at the centerline. A 2x8 notched 1" deep at the
bottom has the same remaining depth as a 2x7, but only half the
strength at that location. The corner of the notch creates a stress
concentration and a place for a crack to start propagating.
Cheers, Wayne
RicodJour
> On 10/4/2010 8:41 AM, RicodJour wrote:
>
> > On Oct 3, 10:06 pm, Mikepier<mikep...@optonline.net> wrote:
> >> Thanks for everyone's input. I might just play it safe then and just
> >> run seperate12/2's.
>
> >> Now to another subject without starting a new thread: is there a
> >> certain guidline on where to drill holes in 2X8 joists? Can I feed
> >> 2-12/2 romex's into one hole? How big of a hole can I drill?
>
> > Way bigger than you need for four 12/2. Some electricians drill more
> > and smaller holes, but I think that's primarily because they lost the
> > chuck key and don't want to change the bit.
>
> >http://www.qis-tx.com/images/newsletter.0605b.gif
>
>
> holes also? I'm thinking no it doesn't mean that, but wasn't sure.
No. Holes and notches are a bit different in their effects on stress
concentration. Holes are less problematic (I'm trying really, really
hard not to make some innuendo with that one!), so that's why I advise
to avoid notching if at all possible.
R
RicodJour
Yep, you're right. I have a better diagram in my Code application,
but it's more work to get it online, so I took the - surprise! - lazy
way out and posted a link that answered Mike's question. I'll try to
get a more definitive diagram posted.
R
RicodJour
I'm not sure about your numbers, but yes, the notch reduces the
overall strength whereas a hole usually does not.
R
RicodJour
The difference in patching a 2" x 2" hole in a drywalled ceiling is
not all that much less than patching a 4" x 12" hole, and, like I
mentioned earlier, you should avoid notching. Notching affects floor
stiffness and deflection, holes don't.
You'd also be required to cover each notched wire crossing with a
metal plate, and that can create a small lump in the ceiling. Maybe
not a big deal, but you'd have to feather out the patch more than a
flush patch.
BTW, my purpose here is not to always make less work for you, it's to
help you to always do better work with the least amount of effort
possible.
R
Mikepier
> help you to always do better work with the least amount of effort
> possible.
>
> R
I appreciate all the inputs from everyone, thanks.
RBM
"Steve Barker" <ichase...@notgmail.com> wrote in message
news:LfWdnagyWKtYYDTR...@giganews.com...
Personally, I prefer using GFCI receptacles at each and every box, but you
could have used a double pole GFCI breaker, then alternated with standard
outlets
RicodJour
> On Oct 4, 12:35 pm, DD_BobK <rkaza...@gmail.com> wrote:
> > On Oct 4, 6:41 am, RicodJour <ricodj...@worldemail.com> wrote:
>
>
> > Rico-
>
> > Thanks, a great diagram.
>
> > I remember a while ago someone posted one similar but it also spoke to
> > the prohibition of holes in the "bearing zone".
>
> > Something like "no holes within xx" of the end of the joist /
> > beam" ? Bearing zone or shear zone? I dont remember the details &
> > cannot find the thread or link.
>
> Yep, you're right. I have a better diagram in my Code application,
> but it's more work to get it online, so I took the - surprise! - lazy
> way out and posted a link that answered Mike's question. I'll try to
> get a more definitive diagram posted.
Woot! Even better, I just found the 2009 IRC online. Here's the
pertinent page in glorious full color black and white:
http://publicecodes.citation.com/icod/irc/2009/icod_irc_2009_5_sec002_par027.htm
No mention of prohibiting holes at any point along the joist. That is
odd, as I do remember seeing such a restriction somewhere. Here's
another, more specific diagram from Bloomington, IN, but still no
restriction on drilling near the joist bearing points:
http://www.ci.bloomington.mn.us/handouts/53/53znotch.pdf
Here's the main IRC page. Bookmark 'em, Danno!
http://publicecodes.citation.com/icod/irc/2009/index.htm
R
George
> On 10/4/2010 7:14 AM, George wrote:
>>> On 10/3/2010 7:20 PM, Mikepier wrote:
>>>> I have to run 4 new circuits for a kitchen I am helping to remodel for
>>>> a friend of mine
>>>>
>>>> 1-Fridge
>>>> 1- Microwave/Range hood
>>>> 2-counter outlets ( as required by code I was told)
>>>>
>>>> The runs from the kitchen to the panel is very long and I also have to
>>>> drill through several ceiling joists. I was thinking of running 2-12/3
>>>> cables instead of 4-12/2 cables. Is this allowed by code? I think
>>>> about the fridge and microwave.
>>>
>>> If you insist on drilling less holes, you'd be better off with a couple
>>> runs of 12/2/2. You'd have a proper neutral for every circuit that way.
>>> You have issues sharing neutrals with GFCI outlets.
>>>
>>
>> But in this case the GFCIs don't know anything about the neutral being
>> shared because they are connected downstream.
>
> ok, go ahead and try that.
>
Works fine. Draw the circuit out on the back of an envelope. The GFCI
works by looking at the differential in the current of the neutral and
the hot leg of its internal outlet and any downstream outlets. If the
GFCI is downstream from the shared neutral that neutral under normal
operating conditions is carrying the same current as the hot leg. Same
is true of the GFCI (if used) on the other leg.
Steve Barker
the load side it would trip the gfci, OR that if there was a trip, it
would trip both legs or something to that effect. I've never actually
finished my project, so i don't know. I actually wasn't planning on
putting any gfci's on there at all, so i rekon it really doesn't matter. <G>
Steve Barker
that's a real good way to get a screw through a wire. Get up in there
and drill the holes.
Steve Barker
no big deal, but it's Minnesota, not Indiana on the bloomington thing.
Doug Miller
>Thanks for everyone's input. I might just play it safe then and just
>run seperate12/2's.
>
>Now to another subject without starting a new thread: is there a
>certain guidline on where to drill holes in 2X8 joists?
Yes: as close to the centerline as possible.
> Can I feed
>2-12/2 romex's into one hole?
Of course.
>How big of a hole can I drill?
No larger than needed; 5/8" is enough to pass two 12/2 cables.
Steve Barker
LOL! ya, i hear ya. thanks for the confirmation.
Steve Barker
ok but it sounds like i have to have BOTH the gfci's broke out of the
shared common at the same point. so i couldn't have one in one box, and
the next in the next box down eh?
aemeijers
yeah, but Indiana has the real one.
--
aem, former 47401 resident, sends...
Wayne Whitney
> ok but it sounds like i have to have BOTH the gfci's broke out of
> the shared common at the same point. so i couldn't have one in one
> box, and the next in the next box down eh?
No, you can do that, you just need to split the mwbc into two circuits
at your first box. The GFCI in box 1 protects the first circuit; the
GFCI in box 2 protects the second circuit, and all the other
recepatcles can be normal receptacles. You feed each GFCI with the
shared neutral and one of the two hot legs; and then for downstream
receptacles, you feed them from the GFCI load terminals and keep the
neutrals separate.
Cheers, Wayne
Steve Barker
Understood. But my wire is already in place. <G>
keith
> On 10/4/2010 10:27 PM, Steve Barker wrote:
>
>
>
> > On 10/4/2010 5:23 PM, RicodJour wrote:
> >> On Oct 4, 3:39 pm, RicodJour<ricodj...@worldemail.com> wrote:
> >>> On Oct 4, 12:35 pm, DD_BobK<rkaza...@gmail.com> wrote:
> >>>> On Oct 4, 6:41 am, RicodJour<ricodj...@worldemail.com> wrote:
>
> >>>>>http://www.qis-tx.com/images/newsletter.0605b.gif
>
> >>>> Rico-
>
> >>>> Thanks, a great diagram.
>
> >>>> I remember a while ago someone posted one similar but it also spoke to
> >>>> the prohibition of holes in the "bearing zone".
>
> >>>> Something like "no holes within xx" of the end of the joist /
> >>>> beam" ? Bearing zone or shear zone? I dont remember the details&
> >>>> cannot find the thread or link.
>
> >>> Yep, you're right. I have a better diagram in my Code application,
> >>> but it's more work to get it online, so I took the - surprise! - lazy
> >>> way out and posted a link that answered Mike's question. I'll try to
> >>> get a more definitive diagram posted.
>
> >> Woot! Even better, I just found the 2009 IRC online. Here's the
> >> pertinent page in glorious full color black and white:
>
> >> No mention of prohibiting holes at any point along the joist. That is
> >> odd, as I do remember seeing such a restriction somewhere. Here's
> >> another, more specific diagram from Bloomington, IN, but still no
> >> restriction on drilling near the joist bearing points:
> >>http://www.ci.bloomington.mn.us/handouts/53/53znotch.pdf
>
> >> Here's the main IRC page. Bookmark 'em, Danno!
> >>http://publicecodes.citation.com/icod/irc/2009/index.htm
>
> >> R
>
> > no big deal, but it's Minnesota, not Indiana on the bloomington thing.
>
> yeah, but Indiana has the real one.
Bloomington Illinois is closer to Normal. ;-)
HerHusband
> a friend of mine
> 1-Fridge
> 1- Microwave/Range hood
> 2-counter outlets ( as required by code I was told)
> The runs from the kitchen to the panel is very long and I also have to
> drill through several ceiling joists. I was thinking of running 2-12/3
> cables instead of 4-12/2 cables. Is this allowed by code? I think
> someone mentioned for the counter outlets is fine, but I'm not sure
> about the fridge and microwave.
You'll need to run dedicated circuits for:
1. Refrigerator
2. Microwave
3. Dishwasher
4. Kitchen Outlets (odd)
5. Kitchen Outlets (even)
6. Kitchen Lighting
7. Range
8. Wall Ovens that are not built-in to the range
9. Garbage Disposal
If the range hood is not part of the microwave, it can be placed on the
lighting circuit (not the outlet circuit).
The kitchen outlets need to be GFCI protected, either with dedicated
breakers, or by using GFCI recepticles as the first outlet in the run.
Ideally, you should run two individual 12/2 cables. While I "think" a
shared neutral in 12/3 is allowed in this case, it doesn't cost that much
to run a second 12/2 cable. If you go with a shared neutral, you'll need
to ensure the circuits are "balanced" in the breaker panel (off each side
of the 240 supply) and the breakers tied together with a bar. Keep in
mind if you have a problem with one of the shared circuits in the future,
or if you end up doing some kind of remodeling, you'll have to shut down
ALL kitchen outlets. Keeping the two circuits isolated allows you to shut
down only the circuit you are working on.
By the way, the kitchen outlets should be spaced no more than 4' apart,
alternating circuits along the run (I spaced ours every 32"). The idea is
to balance the load if you have a toaster plugged in one outlet and a
coffee maker in the next outlet.
Anthony
Steve Barker
dedicated circuits for 1, 2, 3, and 9 are not REQUIRED, but handy. Just
a clarification.
Garbage disposer and dishwasher can easily be on one circuit.
Tom Horne
> "Mikepier" <mikep...@optonline.net> wrote in message
>
> news:06dca548-fdd0-4b7e...@h7g2000yqn.googlegroups.com...
>
> >I have to run 4 new circuits for a kitchen I am helping to remodel for
> > a friend of mine
>
> > 1-Fridge
> > 1- Microwave/Range hood
> > 2-counter outlets ( as required by code I was told)
>
> > The runs from the kitchen to the panel is very long and I also have to
> > drill through several ceiling joists. I was thinking of running 2-12/3
> > cables instead of 4-12/2 cables. Is this allowed by code? I think
> > someone mentioned for the counter outlets is fine, but I'm not sure
> > about the fridge and microwave.
>
> acceptable to do what you propose. You do have to connect them to double
> pole breakers, so both circuits are opened simultaneously.
The requirement for double pole breakers only applies if both of the
ungrounded current carrying conductors terminate on the same strap or
yoke. Passing through the same box is not sufficient reason to invoke
that rule. There is no problem with the required GFCIs for the
counter top receptacles because you only use the 12/3WG for the home
run. Once you get to the first kitchen counter top box you split the
circuit down to runs of 12/2WG from the first GFCI to the remaining
receptacles on that side of the multiwire branch circuit. Likewise
for the Microwave/Range hood and refrigerator circuit; which need not
be twenty amperes and therefore twelve gauge wire; you can run 14/3WG
to whichever box is closer to the panel in wire feet and run 14/2WG
from there to the other outlet. That technique recommends itself to
the food waste disposer and dish washer loads as well.
[RANT MODE] As for the fella or gal coming along ten years from now
if they don't know how to use a tester to assure that all circuits in
a box that they are going to work in are deenergized or understand the
necessity to keep the two ungrounded conductors on the opposite legs
of the panel THEY SHOULD KEEP THEIR UNEDUCATED HANDS OUT OF ELECTRICAL
WORK. I will never be willing to try to dumb down electrical work in
a futile attempt to make it safe for untrained persons to do the work
because I know that it cannot be dumbed down that far. Electricity
can kill! Understand it, respect it, or leave it the hell alone! [/
RANT MODE]
--
Tom Horne
Tom Horne
> On 2010-10-04, Mikepier <mikep...@optonline.net> wrote:
>
> > certain guidline on where to drill holes in 2X8 joists?
>
> joist is only stressed in bending. What this means in practice is to
> stay away (maybe 2 feet?) from the bearing points (over and under wall
> framing) and then to put your holes in the middle of the joist.
>
> > Can I feed 2-12/2 romex's into one hole?
>
> or two 12/3s, without any problem NEC-wise.
>
> > How big of a hole can I drill?
>
> than what you will need, e.g. a 1.25" hole for 4 12/2s would be fine.
>
> Cheers, Wayne
Wayne
The running of multiple cables through the same holes can cause
derating problems. Two 12/3WG cables is only four current carrying
conductors. The THHN conductors used in modern day Non Metallic
Cable, Type NMC, has an ampacity of thirty amperes; even though the
code will not let you use it at more than twenty amperes for most
loads. So you can run four of the 12/2WG, 12/3WG or two of the 12/4WG
cables through the same holes without any problem. If you run cables
having a total of ten or more current carrying conductors through the
same holes the ampacity of the twelve gauge cables drops under twenty
amperes to fifteen amperes, fifty percent, of the THHN conductor's
maximum rated ampacity.
--
Tom Horne
Tom Horne
> Ok, thanks again. Lets add more to this now that I uncovered
> soemthing.
>
> The present stove is on a 40A circuit. I was told newer stoves require
> a 60A circuit.
> Which means now I have to run a new 6/3 with a ground.
>
> How many holes or notches are you permitted to drill through one
> joist? Is it better to drill several small holes , or one big hole?
Notches = NONE, holes that are spaced several times their diameter
apart = Quite a few.
--
Tom Horne
Wayne Whitney
> The requirement for double pole breakers only applies if both of the
> ungrounded current carrying conductors terminate on the same strap or
> yoke. Passing through the same box is not sufficient reason to invoke
> that rule.
Right, but new in the 2008 NEC is a requirement for simultaneous
disconnect for all ungrounded conductors of a multi-wire branch
circuit, so at least a handle-tie is required.
Cheers, Wayne
Wayne Whitney
> The running of multiple cables through the same holes can cause
> derating problems.
That is correct. I didn't bring it up because as you noted it only
affects installation of 5 or more bundled 12/2s.
Cheers, Wayne
RBM
"Tom Horne" <hor...@gmail.com> wrote in message
news:13c38109-48e7-4749...@t3g2000vbb.googlegroups.com...
210.4 has changed , and now requires simultaneous disconnect of all
ungrounded conductors regardless of how or where they terminate.
I wholeheartedly agree with your rant.
HerHusband
>> You'll need to run dedicated circuits for:
>> 1. Refrigerator
>> 2. Microwave
>> 3. Dishwasher
>> 4. Kitchen Outlets (odd)
>> 5. Kitchen Outlets (even)
>> 6. Kitchen Lighting
>> 7. Range
>> 8. Wall Ovens that are not built-in to the range
>> 9. Garbage Disposal
> dedicated circuits for 1, 2, 3, and 9 are not REQUIRED, but handy.
> Just a clarification.
Hmm... I guess you're right. I read NEC 210.52B1x2, and missed the first
part allowing the refrigerator to be on the small appliance circuit.
However, I used to service microwave ovens and it was very common to find
tripped breakers if the microwave had been used while the refrigerator was
running. Granted, they were probably only 15A circuits in older houses, but
it just seems wise to me to dedicate a circuit to any major appliance.
My rule of thumb when we built our house (2003), if you don't unplug it and
put it away, put it on a dedicated circuit.
> Garbage disposer and dishwasher can easily be on one circuit.
I think it depends on the electrical requirements of the disposer
(430.53A?). While it might be OK with the current disposer, who's to say
someone won't replace it with a more powerful one in the future. It's easy
enough to run two circuits, why not.
Anthony
Bob
> However, I used to service microwave ovens and it was very common to find
> tripped breakers if the microwave had been used while the refrigerator was
> running. Granted, they were probably only 15A circuits in older houses, but
> it just seems wise to me to dedicate a circuit to any major appliance.
Another common remodeling blunder is to replace the range hood with a
built-in microwave and connect it to the same circuit as the old exhaust
fan. As was previously stated, the fan cannot be on one of the small
appliance circuits. Typically it's on the lighting circuit.
John Gilmer
"Mikepier" <mike...@optonline.net> wrote in message
>I have to run 4 new circuits for a kitchen I am helping to remodel for
> a friend of mine
>
> 1-Fridge
> 1- Microwave/Range hood
> 2-counter outlets ( as required by code I was told)
>
> The runs from the kitchen to the panel is very long and I also have to
> drill through several ceiling joists. I was thinking of running 2-12/3
> cables instead of 4-12/2 cables. Is this allowed by code? I think
> someone mentioned for the counter outlets is fine, but I'm not sure
> about the fridge and microwave.
I take it you mean to power half of your outlets from one "side" of the
120/240 service and the other half from the other side.
Generally speaking, that's OK.
Potential problems:
1) You have to use a 2 pole breaker for each of your circuits.
2) You may not be able to find "special" breakers (arc fault, GFCI) in
the 240 (+ neutral) style.
3) The savings come from the fact that the neutral currents from the
two complementary circuits tend to cancel. But some harmonics (like you
might see with flourescent lighting and microwave ovens) re-inforce each
other. In practice since most of the neutral currents cancel, the
relatively small amount that reinforces (i.e.: the neutral will carry MORE
current than the "phase" conductor) shouldn't be a problem.
It's an especially good idea if you have "heating" loads such as toasters.
They don't generate harmonics.
You should install GFCI outlets individually (rather than using one GFCI
outlet to protect "downstream") and use a pigtail from the common neutral
rather than "wiring through" the outlet. An open neutral can cause MAJOR
problems.
Wayne Whitney
> 3) The savings come from the fact that the neutral currents from the
> two complementary circuits tend to cancel. But some harmonics (like you
> might see with flourescent lighting and microwave ovens) re-inforce each
> other.
I believe that only occurs in 3-phase MWBCs, not 1-phase MWBCs
Cheers, Wayne
tra...@optonline.net
> "Mikepier" <mikep...@optonline.net> wrote in message
>
> news:06dca548-fdd0-4b7e...@h7g2000yqn.googlegroups.com...
>
> >I have to run 4 new circuits for a kitchen I am helping to remodel for
> > a friend of mine
>
> > 1-Fridge
> > 1- Microwave/Range hood
> > 2-counter outlets ( as required by code I was told)
>
> > The runs from the kitchen to the panel is very long and I also have to
> > drill through several ceiling joists. I was thinking of running 2-12/3
> > cables instead of 4-12/2 cables. Is this allowed by code? I think
> > someone mentioned for the counter outlets is fine, but I'm not sure
> > about the fridge and microwave.
>
> I take it you mean to power half of your outlets from one "side" of the
> 120/240 service and the other half from the other side.
>
> Generally speaking, that's OK.
>
> Potential problems:
>
> 1) You have to use a 2 pole breaker for each of your circuits.
> 2) You may not be able to find "special" breakers (arc fault, GFCI) in
> the 240 (+ neutral) style.
Arc fault is not required in a kitchen. 2 pole GFCI breakers are
readily available and not hard to find. However they are usually
considerably more expensive than two single pole GFCI breakers, which
could be a factor and negate some or all of the savings in wire. But
he could also use two GFCIs in the kitchen for each circuit instead.
> 3) The savings come from the fact that the neutral currents from the
> two complementary circuits tend to cancel. But some harmonics (like you
> might see with flourescent lighting and microwave ovens) re-inforce each
> other. In practice since most of the neutral currents cancel, the
> relatively small amount that reinforces (i.e.: the neutral will carry MORE
> current than the "phase" conductor) shouldn't be a problem.
>
> It's an especially good idea if you have "heating" loads such as toasters.
> They don't generate harmonics.
I don't see how in the world this could ever be a consideration in a
shared neutral circuit in a residential application. You'd have to
have a huge phase shift in a significant portion of the current for
that to be a consideration. I don't know of any such loads that are
intended to be plugged into a kitchen outlet.
>
> You should install GFCI outlets individually (rather than using one GFCI
> outlet to protect "downstream") and use a pigtail from the common neutral
> rather than "wiring through" the outlet. An open neutral can cause MAJOR
> problems.
He can use a GFCI breaker or he can install one GFCI at the first
outlet in each half of the circuit and that will protect the
downstream outlets. There isn't anything different about a shared
neutral circuit that requires individual GFCIs.