How many 30A outlets on a circuit?

[Mustang51js]

Some of the things I feel they change for the hell of it, take pool grounding, it used to be a #8 around the pool, then in 2008 they changed it to a 3 foot grid all around the pool costing people thousands extra. Well now the new code coming out gets rid of that grid ring and goes back to the #8. I just figured it was weird that if the #10 ground is good up to 60 amps then it shouldn't matter if it's on a 30-60 amp breaker.

 

[Mustang51js]

Edit, wrong thread

 

[Sneeze357]

Contrary to popular belief the codes make sense and they don't just sit around and dream them up.

I'm going to have to strongly disagree with that. The book wouldn't be half as thick as it is if that were true. And we wouldn't be having this discussion about downsizing wire when downsizing a breaker for no apparent reason. I'd love somebody to show me the reason for this and how it makes sense.

I wonder how much of the book is a result of electrician's unions?

Now the new owners don't have to worry because it was inspected.
Or should they worry???

Just because a county inspector signed off on something should never mean "don't worry it's ok".

 

[Norcal]

I'm going to have to strongly disagree with that. The book wouldn't be half as thick as it is if that were true. And we wouldn't be having this discussion about downsizing wire when downsizing a breaker for no apparent reason. I'd love somebody to show me the reason for this and how it makes sense.

I wonder how much of the book is a result of electrician's unions?


Just because a county inspector signed off on something should never mean "don't worry it's ok".

I think you'll find more stuff in there at the behest of manufacturers, like AFCI's, bubble covers, etc.

 

[sberry]

Some of that is likely true but this isn't the case in question. I am surprised it is as short as it is considering the amount of equipment in the world and the speed of recent change. Grounding and gfci were changes, I still know people till recently,, thought grounding was dumb.
I can see plain as day the way I started feeling like I really knew something cause a 12 went on a 20 and also read the V drop tables and a little about wire sizing. I had poor training over a bar stool and most people never knew I didn't know.
It took me a long time to really become instinctual about an electric service. When they invented it there were not the alternate pathways we see today etc, its more than making it work and yes for myself its about passing it on in a safe manor.


I did a lot of half *** design, today I am really better about looking at it first and copying as closely as I can. If I got to invent some new deal no one else uses or feel it needs to be 2 sizes bigger than everyone elses I got to wonder why.

I hadn't really wired a new house from start to finish till I was 40 maybe, anyway made about a half dozen minor mistakes,,, not one related to insufficient anything or improper overcurrent.

 

[Sneeze357]

Some of that is likely true but this isn't the case in question.

Explain. Give me a good reason for downsizing my wire. Just one.

I'm not saying every rule in the NEC is made up BS, but certainly, several of them are.

Forget the NEC for a minute. Somebody tell me how it is safer to run 10ga wire to a 30A outlet than it is to run 8ga wire? Common sense tells me, the more wire, the better. Common sense also tells me if I changed out the 8ga for 10ga, it would be a downgrade, not an upgrade.

And then they still allow EMT grounding. Anybody here think that is a better grounding method? *sigh*

 

[Norcal]

Explain. Give me a good reason for downsizing my wire. Just one.

I'm not saying every rule in the NEC is made up BS, but certainly, several of them are.

Forget the NEC for a minute. Somebody tell me how it is safer to run 10ga wire to a 30A outlet than it is to run 8ga wire? Common sense tells me, the more wire, the better. Common sense also tells me if I changed out the 8ga for 10ga, it would be a downgrade, not an upgrade.

The reasoning I believe, is if your increasing your conductor size, then you need to increase the grounding conductor size as a fault clearing path.

I did say it earlier, no good deed goes unpunished, there it is again.

 

[alfredeneuman]

And then they still allow EMT grounding. Anybody here think that is a better grounding method? *sigh*

EMT correctly installed, provides a much better ground path than a ground wire, believe or not.

 

[Sneeze357]

The reasoning I believe, is if your increasing your conductor size, then you need to increase the grounding conductor size as a fault clearing path.

Still makes no sense if a 40A circuit is allowed to use that cable but a 30A isn't. Just because they said it needs to be done does not constitute a good reason. And then there is the EMT thing again...

EMT correctly installed, provides a much better ground path than a ground wire, believe or not.

A thin steel tube provides a better ground path than a solid copper wire of the correct size for the amperage? No it doesn't.

And the possibility of it being installed incorrectly is much, much higher.

 

[Norcal]

You have your choice, use the 8/3 NM cable & be a hack, or do it right & grumble about the requirements.

 

[cmanningjr]

Are we confusing the grounding conductor and the grounded conductor?? They are 2 different animals..

The #10 gauge wire in the 8/3 nm is perfectly fine for a grounding conductor in a 220v circuit.

The problem comes when you want to use it to feed multiple 120v circuits. Then you are using it for a grounded conductor. (Neutral)

So, in order for it to be safe and correct, you would have to use a 4 wire circuit just like in a sub panel system.

If you are going to use a spider box to move to remote locations. Does it have over current protection built in??
If not then it probably needs to be looked at for some protection..

Be safe!!!


Sent from my iPhone using Tapatalk

 

[skiingman]

The reasoning I believe, is if your increasing your conductor size, then you need to increase the grounding conductor size as a fault clearing path.

I'm not sure I completely follow this. Do I have this right:
-10/3 romex with 10ga bare ground is required for this 30 amp multi outlet branch circuit.
-8/3 romex with 10ga bare ground will have lower voltage drop and lower temperatures in service, but is disallowed by the 250.122B
-250.122B protects against someone using a 10 gauge ground on a 600 foot SIXTY amp run to a parking lot lightpost, which could have a very real chance of melting before a fault cleared.

My question is are there any other sorts of faults that are more dangerous (safety is the NEC mission, right?) when the ungrounded/grounded wire is larger than the EGC, whilst protected by a OCPD based upon the smaller ground? Or did the CMP just choose to ignore/discount any wire upsize usage outside this specific voltage drop scenario?

If there isn't some other smoking gun I'm missing, I think it's pretty wild to call it "hack" to ignore the NEC on this issue. It seems quite a trifle. If that's "hack" and you don't have a better reason than "NEC says so" I have to ask at what point you'd stop if the NEC said you shall sell all your possessions and worship Square D.

Especially since, as far as I can tell, you COULD run a thousand foot spool of 14/2 out to the edge of your property, bolt a short, and have a NEC approved method of testing trip curves for hours at a time.

 

[Norcal]

250.122(B) is clear, & if you pick & choose what you want to comply with then that is hack work, the OP has chosen to oversize conductors, which brings that code section into play & then a 10 AWG grounding conductor is not adequate.

 

[alfredeneuman]

A thin steel tube provides a better ground path than a solid copper wire of the correct size for the amperage? No it doesn't.

Steel has 10% the conductivity of copper. Do you really think that you'll be able to compress that thin steel tube to less than 10 times the actual copper wire size (without the insulation)?

Especially since, as far as I can tell, you COULD run a thousand foot spool of 14/2 out to the edge of your property, bolt a short, and have a NEC approved method of testing trip curves for hours at a time.

One of the thing some of electrical instructors do is take a 500' spool of #12, strip the ends, and plug the ends into 120 volt electrical outlet. It draws about 5amps, because of the resistance of the wire, is not nearly enough to clear a fault from even a 15 amp circuit breaker. (A screwdriver placed into the middle of the spool will magnetize the screwdriver, though.)

 

[skiingman]

250.122(B) is clear, & if you pick & choose what you want to comply with then that is hack work, the OP has chosen to oversize conductors, which brings that code section into play & then a 10 AWG grounding conductor is not adequate.

Wow. Praise ITE, what does the good book by the CMP apostles say you should do when an electrical engineer tells you something that challenges the good book? Like that conduit is not acceptable as an egc in all situations. The book says it is with little qualification.

 

[2ManyProjects]

Are we confusing the grounding conductor and the grounded conductor?? They are 2 different animals..

I don't think "we" are confusing them; but it appears that you are.

The #10 gauge wire in the 8/3 nm is perfectly fine for a grounding conductor in a 220v circuit.

Correct.

The problem comes when you want to use it to feed multiple 120v circuits. Then you are using it for a grounded conductor. (Neutral)

INcorrect.

That "8/3 NM" is already a FOUR-conductor cable; the bare ground is NOT counted in the type designation (except sometimes by the explicit notation "w/g", for "with ground"), as the "/3 part refers ONLY to current-carrying conductors. So if/when using that "8/3 NM" for a (purely) 240V circuit, the (white) "Neutral" conductor is simply not used (and in such cases, one REALLY ought to use 8/2 NM-B); but when using it for a 120V MWBC, the (white) Neutral conductor is required, and needs to be connected to BOTH branches of the MWBC; the (bare copper) EGC still remains just an EGC.

 

[cmanningjr]

I don't think "we" are confusing them; but it appears that you are.







Correct.







INcorrect.



That "8/3 NM" is already a FOUR-conductor cable; the bare ground is NOT counted in the type designation (except sometimes by the explicit notation "w/g", for "with ground"), as the "/3 part refers ONLY to current-carrying conductors. So if/when using that "8/3 NM" for a (purely) 240V circuit, the (white) "Neutral" conductor is simply not used (and in such cases, one REALLY ought to use 8/2 NM-B); but when using it for a 120V MWBC, the (white) Neutral conductor is required, and needs to be connected to BOTH branches of the MWBC; the (bare copper) EGC still remains just an EGC.

No, I'm not confused. If you had payed attention I was asking a question to clarify the conductors.

In that case I was COrrect...



Now, you are correct on the code reference 250.122 (B)

But that has nothing with what he wants to do.

But since "you" brought it up:

Look at the chart on page 70-125,

It states:

Over current devices Ahead of equipment, conduit ect not exceeding 60 amps calls for a minimum copper ground of 10 awg.

I guess I missed the part where he was running cable tray or a raceway..

He's planning on using romex. Assuming it is 8/3 wg. Flip over to article 334.




Sent from my iPhone using Tapatalk

 

[Sneeze357]

You have your choice, use the 8/3 NM cable & be a hack, or do it right & grumble about the requirements.

Just because I refuse to follow a stupid and pointless rule does not make me a hack. Now, if I said "to hell with all ground wires", that would make me a hack. To do it the way the NEC wants is not the "right" way, they are not making any sense. I can come up with derogatory words for people who blindly follow the rules, too.

I simply asked for one reasonable explanation of why this would be required. You can't come up with one. Just agree with me that this is a stupid rule they made for no apparent reason. Quit trying to argue! I would bet that the county electrical inspector wouldn't even catch this or care if he did.

If someone could come up with a good reason for this then I have no problem following it. I'm still waiting.

Steel has 10% the conductivity of copper. Do you really think that you'll be able to compress that thin steel tube to less than 10 times the actual copper wire size (without the insulation)?

Yes. Compress a piece of 1/2" EMT in a hydraulic press and you'll end up with about as much metal as a 10ga copper wire, but it will be steel and not copper.

That is also totally ignoring the fact that EMT is made of many many pieces stuck together, copper would be a solid piece run all the way back to the panel. EMT uses lose joints, not wire nuts. Beside that nobody ever "sizes" EMT based on it's current handling ability - the way you should with a ground wire. Even if I used EMT I would run a ground wire inside.

My point here is that the NEC is being totally ridiculous on both ends of the spectrum with this issue.

 

[sberry]

Just because I refuse to follow a stupid and pointless rule does not make me a hack. Now, if I said "to hell with all ground wires", that would make me a hack. To do it the way the NEC wants is not the "right" way, they are not making any sense. I can come up with derogatory words for people who blindly follow the rules, too.

I simply asked for one reasonable explanation of why this would be required. You can't come up with one. Just agree with me that this is a stupid rule they made for no apparent reason. Quit trying to argue! I would bet that the county electrical inspector wouldn't even catch this or care if he did.

If someone could come up with a good reason for this then I have no problem following it. I'm still waiting.

I have this same argument about the 5 hp compressor and a 10 cable. As the man said, its a code thing and while I know I aint going to burn the place down with it I do not think all the code is a conspiracy theory.

There is some deep logic behind it but in practical application it wont mean a pinch of **** to us. Just like using a 8 or 10 on a 50A welder circuit.

 

[Sneeze357]

I do not think all the code is a conspiracy theory.

I don't either. That doesn't mean that at least some of it isn't ridiculous made up BS that was put there by an electrician's union, a MFR with deep pockets, or a stupid politician. Am I wrong?

As a thing that is there purely, 100% for safety, I think the NEC needs to be modified, simplified, and justified.

 

[Mustang51js]

I don't either. That doesn't mean that at least some of it isn't ridiculous made up BS that was put there by an electrician's union, a MFR with deep pockets, or a stupid politician. Am I wrong?

As a thing that is there purely, 100% for safety, I think the NEC needs to be modified, simplified, and justified.

I think a lot of it is for the lawyers to do the blame game.

 

[2ManyProjects]

Just because I refuse to follow a stupid and pointless rule does not make me a hack.

Well, I suppose that depends on one's definition of "Hack". Arguably, deliberately ignoring NEC requirements, even tho' you are fully aware of them, just because "I know better" (when you really don't) qualifies in spades.

Now, if I said "to hell with all ground wires", that would make me a hack. To do it the way the NEC wants is not the "right" way, they are not making any sense.

Or, you simply don't understand the rationale behind the requirement, and are arrogant enough to believe that if you don't understand it, it must not matter.

I can come up with derogatory words for people who blindly follow the rules, too.

It's not "Blind Faith" when you understand the logic behind the code.

I simply asked for one reasonable explanation of why this would be required. You can't come up with one.

I would have thought it was obvious. Try this:

The NEC requires that when the main conductors are "upsized", presumably to ameliorate voltage drop over a long run, the EGC must ALSO be upsized "proportionally". That is a perfectly reasonable requirement. To understand this, you have to look at the purpose of that EGC, and why it is there in the first place: It is to provide a low-resistance path back to the origin (i.e., ground) when the "normal" path for that return current is interrupted due to a fault or malfunction.

So presume for a moment that there IS some sort of fault in the circuit which prevents the Neutral from doing its job. If the (already relatively small, compared to the main conductors) EGC is made comparatively still smaller by NOT upsizing it as code requires, it will produce a significantly higher resistance over that same long run which required upsizing the other conductors. If that resistance is TOO high, the return current will (to at least some extent) now seek some other route back to ground -- possibly through a Human. Ooops!

Or, if perhaps this is a "pure" 240V circuit with no Neutral, and one of the hot legs has inadvertently shorted to the EGC, that grossly undersized EGC could conceivably have to carry the full circuit-capacity current, (or more, depending on the breaker's trip curve) for some indefinite period of time. And being both undersized AND an exceptionally long run, that WILL heat up that EGC, possibly to the point of melting insulation, starting a fire, etc.. Ooops! Again.

Just agree with me that this is a stupid rule they made for no apparent reason.

Sorry, can't do that. As shown above there ARE good reasons for the requirement.

 

[Sneeze357]

Or, you simply don't understand the rationale behind the requirement, and are arrogant enough to believe that if you don't understand it, it must not matter.

No, I understand just fine. I have still yet to hear a good reason why I would need to do this in my situation. There simply is no rationale.

So presume for a moment that there IS some sort of fault in the circuit which prevents the Neutral from doing its job. If the (already relatively small, compared to the main conductors) EGC is made comparatively still smaller by NOT upsizing it as code requires, it will produce a significantly higher resistance over that same long run

I am not upsizing the wire for a long run so this does not apply here. The 10ga ground is plenty for a dead short across my 30A breaker, is it not? The wire length is approximately 25 feet.

Or, if perhaps this is a "pure" 240V circuit with no Neutral, and one of the hot legs has inadvertently shorted to the EGC, that grossly undersized EGC could conceivably have to carry the full circuit-capacity current

Again, does not apply to this situation. Nothing is "grossly undersized" even if it were a long run.

Let's stay on topic here. Can you justify how changing out 25 feet of 8/3 wire on a 30A circuit would be safer if I pulled that wire out and replaced it with 10/3? A ground wire one size less than the main conductor is allowed in many other circumstances. Why not here?

If I installed a subpanel at the end of my 8/3, instead of an outlet, I could use a 40A breaker, and the ground wire would be the "correct" size. Right? Is it not ridiculous that would be allowed but a 30A outlet would not be?

And yet again I have to point out, if this is such a big issue, why, oh why, is EMT allowed to be the ground?

 

[alfredeneuman]

Sneeze357,

Why did you start the "Can I do this" thread in the first place? Because you are not that knowledgeable.

As soon as someone who knows, and tells you the CORRECT way, you began to voice your opposition rant, and became quite butthurt.

Now, after a week, you know more than the pros.
Congratulations, and good luck to you.

 

[Norcal]

Here is a butthurt form....

http://memeorama.com/****-hurt-report-form/****-hurt-report-form/

 

[sberry]

As a thing that is there purely, 100% for safety, I think the NEC needs to be modified, simplified, and justified.

It is it is and it is. They take changes pretty serious, as for simple you can see from this thread that more words don't help and electric safety has skyrocketed, equipment is better than ever. Most problems are still human error, didn't install or maintain it correct.

It never was intended as a DIY manual.

 

[skiingman]

Here is a butthurt form....

http://memeorama.com/****-hurt-report-form/****-hurt-report-form/

You're the guy who couldn't come up with any reason for the section other than "because it's there" right? Don't go getting all butthurt when those of us who don't do this for a living choose to (safely) ignore that kind of thought free ********.

 

[alfredeneuman]

when those of us who don't do this for a living choose to (safely) ignore that kind of thought free ********.

The only way to know if it's reasonably safe, is to get a permit and an electrical inspection.
The only way to pass an electrical inspection is by following the Code as closely as possible.

Not by some internet consensus

 

[sberry]

I will read if anyone wants to write more about the how and why? Its a legitimate question. With the compressor question the basic answer is in case someone wants to add a bigger motor for a later date it should be required to be over wired.

As for the 8 as a panel feed the likely case for a fault is on a branch circuit of 30A.

 

[sberry]

Not by some internet consensus

This is a jump to a conclusion. There is major agreement about a lot of stuff here and one big one being that 1000;s of people are educated about the difference in the green.bare and the white wire that often seem to go the same place. Some of this is no disagreement what so ever.

The question in case the pro here actually argues his way around, its a matter of what you call it. In the grand scheme of things doesn't mean much.

 

[Trey T]

You don't need rationale, because "it's the LAW"! Yes, NEC is a book of rule that's enforceable by Obama. If you put too many outlets on the 30A, you can be electrocuted by the electric chair!

No.... really, just do as you like and just get on with your life. There's no sense of arguing on this board.

No, I understand just fine. I have still yet to hear a good reason why I would need to do this in my situation. There simply is no rationale.

 

[Sneeze357]

Why did you start the "Can I do this" thread in the first place? Because you are not that knowledgeable.

Just because I am not an electrician does not mean I am not knowledgeable. You have no idea what I know. I asked this question so I could know what the code was. That's it. I don't need to explain why. Just because a person on the internet gave me some advice does not in any way mean I'm going to take it or that I even should.

As soon as someone who knows, and tells you the CORRECT way, you began to voice your opposition rant, and became quite butthurt.

That is ABSOLUTELY NOT what happened! It was explained that there is a ridiculous code that says I cannot do that, and not one person can explain why. Just because the NEC says something DOES NOT make that the only "correct" way to do something.

Here is a butthurt form....

http://memeorama.com/****-hurt-report-form/****-hurt-report-form/

Can't answer the question so you just sling more insults. Is name calling not against the rules here? Run along, I'm trying to have a conversation with the adults.

It never was intended as a DIY manual.

Was it intended to make sense then? It currently does not. (Not even to a well educated long time electrician)

The only way to know if it's reasonably safe, is to get a permit and an electrical inspection.
The only way to pass an electrical inspection is by following the Code as closely as possible.

That is an incredibly stupid and arrogant statement. I already explained earlier in this thread how the electrical inspector completely missed 14ga Romex run exposed on the wall in a 20A circuit in my shop. Illegal in every way and installed by permit by an electrician. Inspected more than once.

I will read if anyone wants to write more about the how and why? Its a legitimate question.

Yes, if anybody can actually come up with a good explanation for this other than "the book says so" I would love to hear it. The name calling needs to stop. You are not right just because you follow a book.

 

[Sneeze357]

No.... really, just do as you like and just get on with your life. There's no sense of arguing on this board.

Oh, thanks, now that I have your permission I can move on.

 

[Sneeze357]

Let's stay on topic here. Can you justify how changing out 25 feet of 8/3 wire on a 30A circuit would be safer if I pulled that wire out and replaced it with 10/3? A ground wire one size less than the main conductor is allowed in many other circumstances. Why not here?

If I installed a subpanel at the end of my 8/3, instead of an outlet, I could use a 40A breaker, and the ground wire would be the "correct" size. Right? Is it not ridiculous that would be allowed but a 30A outlet would not be?

And yet again I have to point out, if this is such a big issue, why, oh why, is EMT allowed to be the ground?

All you big fancy electrician geniuses...can you answer any of this without name calling?

 

[Mustang51js]

All you big fancy electrician geniuses...can you answer any of this without name calling?

No they can't lol, and you could even have a 6/3 and use the #10 ground.

 

[skiingman]

The only way to know if it's reasonably safe, is to get a permit and an electrical inspection.
The only way to pass an electrical inspection is by following the Code as closely as possible.

Not by some internet consensus

This isn't a complicated problem. There is no voodoo involved. It's basic wiring. The code is, as it says, not a design manual. It's a list of things you should and shouldn't do. Sometimes it doesn't make any sense when applied to a real problem. Anything designed by committee (or in this case designed by SEVERAL committees) is going to be internally inconsistent and of limited value in some circumstances. That's life. Some of the 2011 to 2014 chances reflect this nature of the beast.

I've never seen a licensed electrician complete any project of reasonable complexity without doing a few things that could be argued to be code violations, and often several things that are unquestionably violations. Try and find a house where ALL the NM meets the radius requirement, for instance. But I think there is a difference between electricians in practice and internet code warriors. That's why I called Norcal out on calling this "hack" because it violates a snippet of code intended to apply to an entirely different situation, and because Norcal won't provide any justification AT ALL for why it might be a bad idea.

Also an inspection ensures nothing is glaringly wrong. The inspection process isn't designed to stamp things "safe". That's overselling it a bit. My area doesn't do permits, just requires the work to be inspected and certified.

 

[PRH44]

The CMP(code making panel) went soft on this one IMO. Seems to me it was only passed to make it easier to enforce, interpret , understand ,etc. what ever you want to call it. What used to be a hard nosed board that would only change for safety sake is giving in, ..SOFT I tell you! TOOMER is correct voting negative on this one or is he? Well maybe abuse is a good reason. So shall it be written its the law now

(Log #1750)
5- 264 - (250-122): Accept
RECOMMENDATION: Revise to read as follows:
250-122 (b) Increased in size Adjustment for Voltage Drop. Where ungrounded conductors are increased adjusted in size to compensate for voltage drop, equipment grounding conductors, where installed, shall be increased in size adjusted proportionately according to circular mil area of the ungrounded conductors.
SUBSTANTIATION: The current text is limited to voltage drop only and is subject to abuse and misinterpretation (e.g. it was done per the plans, not for voltage drop). The manufacturers [sic] directions often call for conductor to be increased in size, with no explanation for why the ungrounded conductors size is increased, with no corresponding requirement for the equipment grounding conductor to be increased.
PANEL ACTION: Accept.
NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 17
VOTE ON PANEL ACTION:
AFFIRMATIVE: 16
NEGATIVE: 1
EXPLANATION OF NEGATIVE:
TOOMER: The submitter did not provide sufficient substantiation.
[RBA Note: Just as in the original ROP document, underlined text is added, italics is deleted text.

 

[Sneeze357]

That's why I called Norcal out on calling this "hack" because it violates a snippet of code intended to apply to an entirely different situation, and because Norcal won't provide any justification AT ALL for why it might be a bad idea.

This is worth bolding. We all know Norcal hasn't gone all day without reading this thread, but he is strangely silent. All I wanted was a little justification for what you say is the "correct" way to do something. That is reasonable isn't it? If you can't justify something or explain why then don't suggest it as the only possible way to do things.

 

[sberry]

Ask for the explanation of a way around it then you wont be a hack.

 

[alfredeneuman]

The last line on the Internet Butthurt Form Norcal posted is:
"I realized arguing on the internet is usually pointless and found something else to with my time"

This is probably good advice and he took it, just like others here should do.