Wire Size For A 60 Amp Breaker ,.According To The NEC ??

[Sberry]

Well absolutely a machine rated to 100% would be different and it is list6ed on the nameplate as well as in the listed instructions in the machine.

Infact....MOST residential circuits are just that.

Ya, gues we missed that the fisrt couple times I mention that.

 

[LD1]

No one said everything could be wired to a number 10,,,, but ever notice when this comes up, very little fact, all,,, I taught Edison everything he knows and to tell the truth a lot of "industrial " electricians not all that impressive with code knowledge and never really had to deal with inspections,,, yet they seem to know all kinds of them, more than the rest of us for sure. Saw one a while back,,, the electrician from work wired a 7.5 motor with a 12 cable.
But,,, does anyone read any installation manuals? Or the instructions? Makes a guy wonder how Lincoln Electric quotes and follows NEC with instruction manual with millions of welders allowing a number 12 wire on a 50A circuit? Wouldnt a guy think,,,,,,, this is code for 75 years,, wonder why they havnt changed it?

What's wrong with that?

 

[Sberry]

I have a question. Art 210.21 B 1 exception 2,,, what exactly does this mean?

 

[MAX-24-Dean]

I have a question. Art 210.21 B 1 exception 2,,, what exactly does this mean?

Correct me if I'm wrong, but I think the link below "Section 630-11" will answer what it means.

@Sberry As the first post made clear, this is clearly a homeowner, not a large industrial facility, so I do not see how your comments are relevant, nor why you thought they were relevant.

I think it is on you to quote the relevant section of the NEC that allows what you are advocating. e.g. Section 630-11 of the National Electric Code does not appear to support your assertions. The calculations for reducing the wire size require a very specific set of information to be on the nameplate of the welder in question to rate the outlet in any way other than normal NEC processes, and that section of the code points that the derate is specific to a specific device, and by the way only for welders with duty cycles less than 100%. I would also point out that is increasingly rare for commercial welders not to have 100% duty ratings in today's industrial environment.

Thanks @grsthegreat and @LD1 for the informative comments.

All the best,

Peter

 

[Sberry]

The whole point of this is,,,, not telling anyone to wire 10 cable to a 60 but that it might not be as dangerous as it might appear at first glance as long as its not overloaded to start with. Someone make a statement like that and it brings all the "cant put a breaker bigger than a 30 on a 10 wire crowd out which is not true. Its done all the time. Its done for hard wired equipment, taps, fixture wires and all those little cords plugged in are small compared to the breaker, based on their short circuit rating not their actual load capacity,,, simply like fixture wires. Whole house is full of 16 wires connected to 20A breakers, they are in a fixture.

 

[Sberry]

What makes this somewhat a farce is a guy comes along and the same crew cheerfully explains how to cobble a 259 Dialarc t5o a dryer circuit, it gets an atta boy or my7 favorite, guy buys a home built parts washer, doesnt know 220 from 210 and someone, suposedly with a paper in his pocker explains to this diy guy how he can make an adapter to the 50A car charger in his garage,,, I say,,, wait a minute,,, no,,,, cheer him on, when we splain the 16 cord not rated fore thaty,,, he knows cause he rode in a truck somewhere,, explains how a 18 wire will trip a 50,,, which may be true but we aint allowed to wire it that way,,, no cheer him on.
Guy explains a legal welder circuiot,,,, oh no but gives a guy atto boys for hooking all his welders to 80A circuit. Not a word about it though, Half a dozen got to jump on twith the theory that all the breaker does is protect the wire in the wall,,, point out the difference and noooooooooo

 

[Sberry]

what you are advocating

Wasnt advocating, was simply saying it may be allo9wed.

 

[CobyRupert]

A little bit of knowledge is a dangerous thing.

Generally, but with many exceptions and nuances, step 1 is cable has to be sized to 125% of the load. Step 2 is the breaker has to be sized to the ampacity of the cable. (NEC Article 240) , however, if less than 800amps and not part of a multi-outlet circuit, the next higher breaker size (above the cable’s ampacity) may be used.

The real controversy is do you size the cable based on its 60 degC or 75 degC ampacity rating? Hint: it’s based on the temp rating of the terminations you’re connecting to, not the cable temp rating printed on the wire covering. And if you don’t know terminal’s rating, you have to use the cable’s 60degC ampacity rating up to 100 amps (NEC Article 110).

OP’s situation is very specific. First, it falls under HVAC circuits, which have their own NEC Article 440 section (as do motors and welding recepts). They often require “HVAC rated” breakers or fuses somewhere in the circuit .

We also don’t know if the breaker is protecting a FEEDER or a BRANCH circuit, which are sized very different. There are very specific situations where a feeder breaker can be multiple sizes bigger than the conductor it supplies if it is feeding multiple motor (or HVAC) branch circuits that have individual overcurrent protection.

 

[Sberry]

Yes and that is an explanation worthy of reading.

There are very specific situations where a feeder breaker can be multiple sizes bigger than the conductor it supplies if it is feeding multiple motor (or HVAC) branch circuits that have individual overcurrent protection.

My argument comes with the statement that usually includes ALL,,, such as ALL 10 must etc,,, it comes from the statement ALL the breaker does is.
I happened to read Art 90.7 maybe , dont recall exact but all this is like a web anyway but they do generalize some about the design, the nature even the inspection of listed equipment. As I elude to with the electric range, all the internals sized similar and in accordance with the tap and fixture wires etc. I will have to add a disclaimer of course, someone can find something wrong with that generalization to be sure. I feel we might be able to add to the above there are a few more and /or/but they may involve a different wiring method terminatios etc for sure.

 

[Sberry]

Its not a whole bunch of code its the word ALL. The code is only to show that there are allowances that disprove the word all which is explained in the terms and definitions of the code. When a guy says ALL it does we have to assume he is not aware and his education on this matter is incomplete.