Electric Problem or overloading the circuit

One reason why I am dead against using EMT as a safety ground.

Reply to
clare
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And you are claiming 60 hz induction heating will make that conduit hot???

Reply to
clare

In a parallel conductor (conduit) totally surrounding the load current? where you have both conductors of a circuit running parallel to each other inside the same conduit????

I'd like to see that work.

Reply to
clare

Yes; accept the correction. It's a VOLTAGE increase (difference) of

6.19% Making the assumption that the resistance (or AC impedance) remains the same the WATTAGE will increase by approx. 13%. That should have been fairly obvious?

But the way one often explains it to the technically challenged is to first ask; "If the voltage was say 120 volts and is then doubled to

240 volts, how much more CURRENT will flow (assuming all other circuit components remain unchanged)?

The answer is obviously "Twice as much". One then says '' Well with twice the voltage and twice the current there will be four times power (wattage). Right?". (2 times volts) x (2 times amps) =3D 4 times volt- amps.

That usually gets them thinking and it's then possible to explain the simple math derivation from Ohm's law that Voltage squared divided by Resistance =3D Power (wattage).

And suggest then; so what would happen if the voltage increased by say ten percent? The answer is about 20%. i.e. 1.1 x 1.1 =3D 1.21 (i.e. Twenty one per-cent power increase)!

But I've met electricians who can wire a dream but must understand basic electircity in a manner different to one's own!

Reply to
terry

The handle of a breaker does not have to move to a tripped position when a breaker trips. If there is enough force (as from another breaker) the handle can stay in the on position. Breakers are "trip free" (which you edited out).

As a matter of experience, handle-tied breakers do not always both open if one is tripped by overload. Some brands might.

You can handle-tie 3 breakers for 3 phase circuits. I would expect them to be less likely to all trip.

I would not rely on handle-tied breakers to all trip open. If you want a reliable trip of all poles use a multi-pole breaker instead of a handle tie.

"Common disconnect" means that when the breaker is *manually* turned off all breakers are opened. (The language is "simultaneously disconnect".)

"Common trip" means if one breaker trips by *overload* both breakers open.

They are not the same.

Handle-tied breakers are necessarily "common disconnect". They may or may not be "common trip".

Reply to
bud--

But its that funny Canadian stuff.

The explanation I have heard is 120/240V is the nominal supply voltage (at the service). And 115/230V is the nominal voltage at equipment (after voltage drop). (Would be interesting where 117V comes from.)

The NEC says to use 120/240 for calculations. The values for current in the NEC motor tables are for 115/230V.

IMHO arguments about what is "correct" are useless.

Reply to
bud--

That, my friend, is assuming facts not in evidence. That the conduit gets hot enough to burn paint (as the OP stated) is strongly suggestive that both conductors of the circuit are *not* in fact "running parallel to each other inside the same conduit". If they *are*, then of course there would be no heating. Given the apparent mess that is the OP's wiring, and given his confused description of it, I should say there's no reason whatever to assume that the circuit was installed correctly with both conductors inside the same conduit.

Reply to
Doug Miller

60Hz works for induction cooktops, doesn't it??
Reply to
Doug Miller

Any that passes CSA approval WILL. Don't know about the lame US regualatory bodies.

Reply to
clare

Made in the "good old USA" back in the day when USA still HAD industry.

Reply to
clare

Nope. Induction cooktops use a very high frequency inverter circuit.

Reply to
clare

Me, too.

Reply to
cjt

Once it's converted to 25 KHz +/- :

formatting link

Reply to
cjt

s.com,

Had an electrician out today....the problem was a hot and a ground were fused together inside the panel and a bad breaker. looks like the panel was getting some water in it and making some wires rot. Thanks guys

Reply to
fzbuilder

Well, since I've a little time, I guess I'll have to help you understand the English Language and perhaps a little comprehension assistance too.

In news:hh66do$438$ snipped-for-privacy@news.eternal-september.org, Doug Miller typed:

Sure, links have been posted online as available from the sites you mentioned and many more. I have on the shelf here the 2005 book which serves well yet but is outdated of course in some areas, plus I think it's the 2003 rev; I can't quite make out the writing on the binding. I said I searched for the NEC, NOT for a "book on the NEC" or the "NEC book", etc.. I use it so seldom anymore now I'm retired that paying for it again isn't something I want to do anymore. Normally I can find pieces of it scattered around the 'net to satisfy my needs, should they come up, so that suffices for insuring the latest developments. I've always thought it was something that should be reproduced on the web anyway, and until very recently haven't come across it in full. It's been quite awhile now since I've bothered to look for it, but I've come across at least 3 sources for it now: One the NFPA presentation ala yours, another a micro-fiche scan put online and a third that looks like it might be illegally placed so I don't expect it to be there long. What's really needed is an online searchable database or file so lookups are made more efficient. And before you go off on how "they" deserve to be paid for it, I disagree: Anything akin to rules & regulations belongs on the 'net ala the FCC and other Fed documents such as CFRs etc., state rules & regs, even local gvt rules & regs. Most are online with the exception of small local governments and that's pretty much understandable due to the cost of equipment to maintain such things. Hmm, just thought of another possible source of the NEC; I'll have to take a look at it. If anyone cares I'll post back if it's there.

I could not care less what you think; you do appear to be narcissistic and to have trolish tendencies though, as your posts show quite clearly IMO. So, NO, I hadn't read the 2008 NEC; you're right. And I thanked you for the links to which you had nothing but a trollish response. I knew there were changes since the 2005 but couldn't get a clear and concise explanation of them w/r to your Edison toys. Your childish attempts at redirecting and otherwise changing the subject are lost on me as are anyone else's. It's blatantly apparent that you often cut loose on subjects you know nothing about in fact, as evidenced by your suppositions above. Now it's apparent you go off on self-serving crusades and hope to issue directives to people that are downright silly to begin with and useless to boot. If you want more control, you'll have to go to a monitored group or forums on the subject.

And for dumping your credibility rating into the toilet, on top of a few other things. It's easy to have a few links one can provide; making proper use of them is another story. The para 10.4 reference was nearly useless; however, other parts were useful for the subject, and I have to wonder if you are/were even aware of them.

It's rather telling too, the way you rant as though not having read the 2008 NEC and asking questions about it here were a mortal sin, only because you have it yourself. I even picked up a bunch of info on the 2009 proposals and status; hope you have too, else you're one gigantic ass, using your own methodology.

Boy, you're really challenged in reading comprehension, aren't you? You can't see the "under fault conditions" in that sentence? Or is it that you don't know the scope of the phrase "fault condition"? I don't really care; it's just one more example of your inability to function properly.

No, I meant especially in a miswired case. Where did I say there was an alternative case? It means, especially in the case of a miswire, ... .

But in reality it's seldom the case. With ganged breakers, balanced currents would be the only way one breaker wouldn't be influenced by the other. It's funny, and strange, that you missed the other breaker types that could have been used. Turned out to not require a lot of research to pin it down for my self and get my head around them. Thus I have to assume you simply decided not to part with such information, OR you don't know the specifics of how/why they trip.

No, it appears that way because it actually IS that way.

I never said it could. There's that reading comprehension issue again.

You love the phrase "Edison Circuit", don't you? Stuck in a rut?

=============

Couldn't send this due to a storm apparently killing our avaialable routes out of here and still had a little time left. I went out to the shop, fired up the genset, and grabbed a couple of 15A breakers with holes in the levers to toggle them together. First I tested each one, using two DC power supplies tied togther via diodes. I used DC because I wanted the current limiting abilities of my power supplies. One breaker tripped at about 15.9A, the other one at 16.3A, with long-term loads applied. I was limited to 20A total, less whatever the diodes & supply specs dictated, and I covered them with a plexiglas box to contain the heat. By themselves, they tripped rather readily and strongly once they got hot enough long enough. Then I installed a GenRad bar (they're from a GenRad panel) and tied the two levers together. Very little slop, but some; you could feel it. Applying Common mode current, they tripped at around 16.7 Amps; don't know the time, I wasn't there when they popped. While they were still warm, I removed the current thru one breaker and set my meters to max I and flipped the power on. It measured out at about

19.25 Amps on both my Triplett and Radio Shack Special. I've no scope so I wasn't able to view the waveforms from the supplies, but ... DC is pretty much DC. The breaker gave an initial jump after about 20 seconds, but didn't open and after about 1 1/2 minutes, jumped again, trying to open. Long story short, it still hadn't opened after about ten minutes. My poor power supplies were starting to smell hot, so I suspended the test. Perhaps a sudden surge of many more amps would have created a satisfactory event where it popped both breakers open, but at least in this test, it was never able to overcome the other breaker's resistance. It took very little added physical pressure on the lever to pop it, but still, it didn't open on its own. I then reversed the connections, intending to use the opposite breaker as the driver, and the genset ran out of gas!! I quit! This has turned into a real curiousity fest for me now. I have a couple huge wire-wound rheostats that might take the current I need; I'm going to check. Then I could use 120Vac and perhaps the spare 20A breakers from my own existing panel. I might even pop for a couple of the other type breakers too; it seems there's more here than meets the eye. If the test results so far hold, that makes it pretty dangerous to use a ganged breaker in place of the other type, whose name escapes me at the moment. Also, everyting I've found on ganged breakers so far indicates they're intended to have equivalent loads on each side, which intimates not using them for multi-branch ckts. If my spare time will hold out, that is.

Enjoy;

Twayne

Reply to
Twayne

...

Hoo, mercy! Glad you're still kicking around! That pretty much explains everything. Sure good that no one got hurt in the tub! Thanks for coming back with the solution.

Twayne

Reply to
Twayne

If you pay more attention when you read, you won't make yourself look like such a fool.

I said *nothing* about "book[s] on the NEC". I told you where you can get _the NEC_. Sources include libraries, eBay, Amazon, and major bookstores.

Do I need to look up the ISBN for you too?

[snip a lot of irrelevant garbage -- none of which changes the fact that you haven't the least idea how multiwire branch circuits work, or what the Code provides]

Now that you know where to get a copy of the Code, you no longer have any excuse for not knowing what it says.

Reply to
Doug Miller

UL 1459, its successor, and CSA are the same on these points. What's important in reading them is "properly installed" w/r to their "purpose". Ganged breakers are expected to have the same current in each leg; thus they don't impede each other. Using a ganged breaker in a split or multi- situation would be an improper application. All breakers and fuses are specced and include a time-chart of current vs time for opening so that makes it obvious too.

Cheers,

Twayne

Reply to
Twayne

The US Grid (PSC etc) say it's 120/240 +- 5% and 60 Hz nominal over, I think, 24 hours. THOSE are the specs used transformers outputs. Not in that range? There is a problem or you're in a brownout/overvoltage mode at the grid. The misnomers come from a time when different areas of the country actually did have various nominal voltages such as 115, 117, 120, etc.

Reply to
Twayne

Nope, not at all. You must have a comprehension issue, too. That means you don't get the proper meaning out of the words you read, in case it's too tekkie for you.

Definitely so with a ganged breaker, which you snipped. It's been proven physically in fact.

So did I, you poor non-comprehending dufus. It's easy to make unsupported statements. Like, I'm not so sure you ever even graduated from grade school. Maroon is definitely your color.

Reply to
Twayne

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