30 amp from two 15 amp breakers

Hey All - got a question about something thats been bugging me tonight (dont worry im *not* going to do this, im just interested to know if its possible).

Is there any difference between a 30 amp breaker (2 hots, one out of each pole of the breaker), and two 15 amp breakers, one hot coming out of each?

ie, if you wired a 30 amp plug, would both of the above equate to the same thing? What problems would arise, etc?

sorry if its a dumb question :)

Reply to
barnesrich
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It's a dumb question.

hvacrmedic

Reply to
RP

Well electrically it should be the same but separate breakers won't trip off together unless linked which may or may not be possible.

By plug I presume you mean receptacle. The problem that would arise would be someone going to work on it or equipment plugged into it might only switch off one leg and get a nasty surprise. This might be ok in a temporary situation with outlet and both breakers suitably labeled but nothing you'd want to do permanently. Labels fall off and people leave, forget or simply don't understand the concept.

Reply to
Steve Kraus

This is Turtle.

Your Question is just cloudy to understand.

A 30 double Breaker hooked up and you can pull 2 -- 30 amp circuits off of it for 220 service or 2 - 30 amp single circuits or 2 single circuits to the house.

A 15 double Breaker hooked up and you can pull 2 - 15 amp circuits off of it for 220 service or 2 - 15 anp single circuits or 2 single circuits to the house.

No a 30 amp Double circuit and a 15 amp double circuit would not be the same as to what it would do or let mess up using one or the other. If you hooked up a 15 amp appliance to a 30 amp circuit. it could burn the appliance up and the house too but still not trip the circuit breaker.

So a 30 double breaker circuit and a 15 amp double breaker circuit is not the same.

TURTLE

Reply to
TURTLE

Yeh, there are three differences.

1) A 30a 240v breaker (I think that is what your are referring to) puts out 30a 240v. Your pair of 15a 120 breakers put out either 15a 240v or 30a 120v (or even 0a 0v) depending on how your circuit was. 2) The 240v breaker will trip both sides simultaneously; the pair of 120v breakers won't. 3) The 240v breaker can't be put in the circuit box stupidly (see previous question); the pair of 120v breakers can.

Don't use the 120v breakers for 240v. And if you have to ask this question, thing about whether you really want to do this project yourself.

Reply to
Toller

Oops I misread your post and thought you were using the two breakers of the same value on different legs in place of a double breaker. That would indeed be electrically the same though not a good idea for reasons cited.

As for the question you really did ask a 30 A two pole breaker would pass

30 A on each leg, not 30 total. In 240 or 208 V usage 30 A would be going out one line and back the other so still just 30 total as it's across two hots. Naturally 30A breakers would not offer proper protection on a 15 A circuit.

And on the 2nd question two individual 15 A breakers would not suffice to feed a 30A recepticle.

Reply to
Steve Kraus

little 15 amp wires carry 15 amps big 30 amp wires carry 30 amps. giving little wires big amps makes big fires. never mix or match any unmatched wires to their breakers. if you do you put the next electrician at risk.

Reply to
buffalobill

Short answer - DON'T DO IT.

Reply to
Joseph Meehan

Wrong. The OP asked about a 30A double-pole breaker vs. two 15A single-pole breakers. *Obviously* not the same.

Reply to
Doug Miller

Yes, there is: the former supplies one 30A circuit at 240V, or two 30A circuits at 120V, depending on how it's wires, and the latter supplies two 15A circuits at 120V. The latter can be combined to supply one 15A circuit at

240V, if you know what you're doing -- and you don't.

Absolutely not.

Risk of fire, chiefly.

Yes, it is.

Reply to
Doug Miller

No question is a dumb question when you don't know the answer. In this case going ahead without guidance could lead to serious issues. I my book that makes it a very wise and good question.

Reply to
Joseph Meehan

Sorry, can't agree. The OP was asking, essentially, if a 15A breaker and a 30A breaker are the same thing. It is obvious that they are not. Hence it's a dumb question.

Reply to
Doug Miller

In the end, yes. But I can see where someone might think a double breaker with a single handle that has "30" written on it is composed of two 15A breakers, not two 30A breakers. It's wrong but it wasn't pulled out of thin air; there is a logic to the wrongness. So not all that dumb a question.

Here's a distantly related question. Is it ever permissible to use a two pole breaker for two 120V circuits not for 240/208? Let's say someone wanted to ensure that when circuit is turned off or tripped the other is off as well. Maybe for some equipment that for whatever reason has two

120V feeds and you wish to enforce that it's completely dead.
Reply to
Steve Kraus

Seems to me pretty obvious that something labelled "30 amp" is a 30-amp breaker, not two 15s. But hey, maybe that's just me.

Certainly. That's no problem at all. In fact, in the situation you suggest, it's the best thing to do.

Reply to
Doug Miller

Sure, why not? It is commonly done on multiwire circuits, though one might call that a 240v. I have a duplex breaker that lets you put either two 240v breakers in the space of one normal 240v breaker, or one 240v breaker and 2 120v breakers; depending on whether or not you remove a handle tie.

Reply to
Toller

: > Is there any difference between a 30 amp breaker (2 hots, one out of : > each pole of the breaker), and two 15 amp breakers, one hot coming out : > of each? : >

: > ie, if you wired a 30 amp plug, would both of the above equate to the : > same thing? : > What problems would arise, etc? : >

: > sorry if its a dumb question :) : : It's a dumb question. : : hvacrmedic : NO, it's not. The only dumb question is the one that doesn't get asked.

Reply to
Pop

Wow, I'm not even sure what the question is. "two hots, one coming out of each pole". That makes for a 30 twin, or a double 30 or....

Reply to
Stormin Mormon

"Would you rather slide down a razor into a barrel of iodine, or drink a bucket of monkey snot?" --The book of stupid questions.

Reply to
Goedjn

learn to write. not only was that impossible to read, but it didn't answer the question.

Reply to
NeedingHelpFindingNone

learn to read (the date)

m
Reply to
makolber

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