Load capacity of 200-amp panel

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No, there is not a single physical current of 400 amps flowing. I've said repeatedly that you only have 200 amps of mx current flowing through the service. That applies to the panel as well.
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On Nov 1, 8:41 am, snipped-for-privacy@optonline.net wrote:

You keep interchanging the meaning of current and power. They are not the same. At no time will there be more than 200 amps of current flowing in the box without tripping a breaker. It doesn't matter how you divide up the loads there will never be more than 200 amps flowing in the box without tripping a breaker. Your terminology saying 400 amps of LOAD is just wrong. But guess what I work with engineers that say it all the time. I know its wrong, they know its wrong but we all know what each other means. The OP made the same mistake and that is why I said he was asking the wrong question or was it the question wrongly.
I tried to clarify what he meant and when I got through it sounded like I was saying there were 400 amps of current flowing, my bad. I was merely trying to indicate he could still power the load he wanted and it didnt take 400 amps to do it.
Jimmie
Jimmie
Im sorry you dont get it. I suggest you get some good books on electrical engineering and try to learn more than the mechanics.
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Now that is simply untrue. Nowhere above have I ever interchanged current and power. But they do need to obey the laws of physics, which in ALL of the above they do. All of the current and all of the power are accounted for and there is 400 amps of current flowing across 120volt loads that accounts for the full 48KVA of power in the service. Capishe?

No shit Sherlock.

No shit Sherlock.

Hmmm, let's see. Your first post you said:
"Assume you are using one leg at 200 amps, that is all the breaker will handle that is 120 volts X 200 amps or 24,000 watts. If you again max out the breaker with 200 amps flowing on both sides that is 240 volts x 200 amps or 48000 watts. Thats the same as 120 X 400 amps. I think the OP wanted to know if he could get a total of 400 amps at 120VAC. Lets rephrase that to could he power 400 1 amp 120 VAC loads from this box under residential conditions. The answer is yes "
Then you apparently changed your mind. When called out on it, you then said " I don't know why I said that, but I was wrong." Now, apparently you knew all along why you said it, it was no mystery.

It wasn't a wrong question. It was a very reasonable question that any homeowner could ask an electrician or electrical engineer. "How many amps of 120volt load is the max that I could hook up to a 200 amp, 240volt service." You've got at least two electrical engineers here and we both say that the answer to the question of how many amps of 120volt load a 200 amp 240v service can supply is 400. You also have about 5 other people who have weighed in and they say 400. The only lonely voice coninuing to say 200 here is you.

And now comes the weaseling. It didn't "sound like it." You did say exaclty that, it's reposted again for you above.
I

If it doesn't take 400 amps to power a 48KVA load at 120volts, then please explain how your math adds up. You claim I'm "interchanging" current and power. In fact, I am not and my math adds up. What is the voltage across the load? 120volts What is the current flowing through the 120 volt loads? 400 amps. What is the power? 48KVA. See how it all works out?
Now let's do it your way. 120volts X 200 amps=24KVA. Where is the other half of the missing power? I've asked that previously and gotten no answer other than the lame "you're confusing power with current." I've supplied the straightforward math for the simple circuit I drew above, where is yours?
Here's the other simple question I'm waiting for an answer to. I tell the homeowner he can power a max of 400 amps of 120 volt eqpt. He goes out and buys four 12KW heaters. The box on each one says 120volts, 100 amps, 12KW. That is how these loads are labeled, are they not? He plugs two in on one side of the hot, two in on the other side of the hot. He now has 400 amps of 120 volt loads powered.
Following your answer, he instead comes home with only two 12KW heaters and only gets to use half the available service power. Why is he only getting half his load if he listens to you? Doesn't that bother you?
In simple terms, for some strange reason, you want to ignore a current passing through a second load and generating power. You don't count current twice in a circuit in a way that would violate Kirchoff's Law. But you do count it twice if it flows through two seperate loads, powering each of them. That is the only way physics explains the power.

Since you want to drag education into it, I've stated my credentials. I have a BS in Electrical Engineering from the Massachusettes Institute of Technology. I spent 16 years in various capacities, many of them engineering, with Intel. Bud, who also says you are nuts, has an Electrical Engineering degree from the Univ of Minnesota Institute of Technology. And precisely what are your qualifications?
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On Nov 2, 8:30 am, snipped-for-privacy@optonline.net wrote:

Geez no freaking way you graduated from MIT. Im done with you.
Jimmie
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Yeah, that's pretty much what I expected, no fact, no answers to the several simple direct questions that are the core of the issue, just emotion.
Here's just a couple more question for you big boy. What is the total power that a 200 amp 240volt service can deliver to a resistance load of heaters? Everyone else that I've seen post here agrees that it is 48KW. Do you agree?
So, I hook up those four 12Kwatt heaters from my example to my 200 amp service. I place two on each side. I now have a balanced 120volt load, 24KW on each side, the total power is 48KW. With me so far? The voltage on each and every one ofl the loads is 120volts. So, if 400 total of amps is NOT flowing through the LOADS, then how do I get 48KW out of the service? Or is it your position that I can only get 24KW out of the service?
Those are the kinds of simple questions any first year EE student can answer. My math adds up, we have yet to see yours.
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Sorry for that comment, I had to go take some insulin.
I ran this buy the engineering staff at work and they agreed with me. Then I realized a few minutes ago that we ARE talking about a residential environment, I deal with industrial installations, mostly testing and installations of UPS's and generators. The point I was trying to make to the OP is that there will never be 400 amps in the box. There will never be 400 amps flowing anywhere.
It appeared to me and the engineering staff that claims were being made that there would be 400 amps of current flowing at 120VAC. This is what I disagreed with. Part of the reason for my argument is that while this MAY be a question a typical home owner could ask I did not view it as such as such, it is also a classical "gotcha question". Usually the question is just tossed out in a classroom for discussion to get people thinking but a few instructors will put it on a test. The guys at work saw it the same way.
I agree that asking if the box will will support 400 1 amp 120 vac loads is a question a home owner may ask and the answer is YES in theory and I have said so. If this was a real homeowner type question the answer would be NO. He would be risking overloading the box.
The only point is that I am making is that there will never be 400 amps of current flowing in the box.The LINE Input will not "see" the load as 400 1 amp 120 VAC loads it will only "see" it as a 200 amp 240 vac load. If you add up all the currents through each individual current paths there will never be more than 200amps. The way I see it 2 120 vac 1 amp loads in series is is going to be one path. There is no node or legitimate sum of nodes where 400 amps is flowing in the box.
A home owner may see it as 400 1 amp 120vac loads but that is not the reality of what is happening in the panel. I think our disagreement is merely a matter of perception of the problem and a matter of perception of each others answers. We both know what we are talking about.
As far as my education, I eventually got my Electronic Engineering degree at University of Miami after attending 3 different universities spread out over 8 years while in the USAF. When I got out of the AF in the early 80s I discovered there wasnt much call for an electronic engineer.The jobs that were open had a very short life expectancy, most engineers were being hired for special projects with little hope of being retained after the project was finished. I then went back to Georgia Tech for a little over a year for my electrical degree. Never finished it up, A very good long term job came along and I made the choice to take it. .
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On Oct 29, 8:24 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

You do not have a physical current of more than 200 amps flowing in the service cable. THAT is what I have been saying all along. That is very different from supporting a LOAD of 400 amps worth of 120volt equipment. And once again, let me point out that I have courteously answered every one of your questions, yet you will not answer the simple direct question I have asked you repeatedly. I even asked it again above, yet you choose to hide from it:
How many amps max are actually flowing in the service cable?
Answer:200
Do you agree, yes or no?
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least two posts, I stated clearly that the neutral carries only the unbalanced current, and if the loads in the two legs are exactly balanced the current in the neutral is zero.
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JIMMIE wrote:

Think heat.
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LOL
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Jimmie: I think the reason this thread has gone so long is that some do not really understand current flow, especially AC (Alternating Current) single phase and may be confusing current flow (amperes) with power (watts/kilowatts).
In some countries also they have only two wires coming into a domestic service (plus ground/earth). So they have a concept of only the two wires of a single phase 230 volt service. One of which is neutral (essentially at zero volts!) and the other at 230 volts (often 50 hertz) to neutral and ground. the size of those dermines the ampere capacity of the service.
Was looking at distribution along a street in Malta; which was attached to the face of the buildings. It comprised four wires. One of which was ground/earth. I think it was green? One of the remaining three was neutral. The other two were most likely 230+ and 230- as it were of a single phase. Or they might have been two phases of a a 3 phase delta/star transformer sub-station secondary at end of the street. The house services along the street were connected alternately to these last two. In other words all services were two wire single phase 230 volt, plus a ground/earth.
Again in one of the Gulf States it was also essentially 230 volts 50 hertz. BUT; in that instance there were the three phases and neutral etc. coming into every residence unit and the circuit breaker panel or CU (Consumer Unit) had three sections one for each phase. The fact that there were some seven large 230 volt 50 hertz AC units in each unit probaly required a heavy service! Residentially didn't see any 3 phase equipment although it could have been hooked up. It was mainly UG.
Other areas of the world may vary; in Sri Lanka for example it was hard to tell what was going on viewing some of the lash-ups on some of the service poles!
Anyway the point of all this is that it's best to understand, no matter where one is, what the electrical service arrangement is. Also that with two wires (plus ground) there can be no doubt .................. a 200 amp service (or whatever it's rated) is just that, 200 amps.
No more (unless overloaded) no less (subject to the recommended 80% rule for prolonged use). Nothing magic about it!
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Thank you. That's exactly what I've been saying all along.
Here's a circuit diagram of a fully loaded, balanced 200 amp service:
-------------- 240 volt source----------- I I a I I b I I I------------------2.4 ohmRes-----------I I I I-----1.2 ohmR-----1.2 ohmR--------I
How much current is flowing in the "service", which is through the voltage source? 200 amps. It supporting one 240Volt 100 amp load and two 120volt 100 amp loads. By every circuit concept I've ever heard of there is but 2 amps flowing in the service cable here. Yet, some would have you believe it 3 amps.
If we want to include the neutral then it looks like this:
+ -- + -- I------------120V----I-------120V--------- I I I I I I I I I I-----1.2ohms------I--------1.2ohms---I I I I-------------------2.4 ohms---------------I
The service now consists of 3 wires. In this case, because it's balanced no current is flowing in the neutral. You can unbalance it, do anything you like and still with a 200 amp service there is only 200 amps flowing in, 200 amps flowing out. And it;s not a "parallel circuit either as Doug has claimed.
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Small correction to my previous post, where I left out a couple of zeros in the text.... Here'e the corrected version.
Here's a circuit diagram of a fully loaded, balanced 200 amp service:
-------------- 240 volt source----------- I I a I I b I I I------------------2.4 ohmRes-----------I I I I-----1.2 ohmR-----1.2 ohmR--------I
How much current is flowing in the "service", which is through the voltage source? 200 amps. It supporting one 240Volt 100 amp load and two 120volt 100 amp loads. By every circuit concept I've ever heard of there is but 200 amps flowing in the service cable here. Yet, some would have you believe it 300 amps.
If we want to include the neutral then it looks like this:
+ -- + -- I------------120V----I-------120V--------- I I I I I I I I I I-----1.2ohms------I--------1.2ohms---I I I I-------------------2.4 ohms---------------I
The service now consists of 3 wires. In this case, because it's balanced no current is flowing in the neutral. You can unbalance it, do anything you like and still with a 200 amp service there is only 200 amps flowing in, 200 amps flowing out. And it;s not a "parallel " circuit either as Doug has claimed.
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a 0.6 ohm load across L1 and the neutral, and NO load across L2 and the neutral (an open).
L1 side L2 side I000000000000000000000000000000000I The 00000s represent trans. windings I------120V----------I-------120V---------I I I I MB1= 200A main breaker Line 1 side I I I MB2= 200A main breaker Line 2 side MB1 I MB2 I I I I I I I-----0.6ohms--------I------ ------I
There will be 200Amps down thru MB1 and thru the load and back up thru the secondary winding using one half of the transformer secondary winding.to form a circular loop.. There will be NO current thru MB2 because there is no current path.
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I havn't heard from Clark Griswold in a while, not since they did the movie about him.
http://www.youtube.com/watch?v=ian6NyXpszw

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Christopher A. Young
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I havn't heard from Clark Griswold in a while, not since they did the movie about him.
http://www.youtube.com/watch?v=ian6NyXpszw


http://www.youtube.com/watch?v=8qc_RYm0ylA&NR=1

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Christopher A. Young
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I havn't heard from Clark Griswold in a while, not since they did the movie about him.
http://www.youtube.com/watch?v=ian6NyXpszw


http://www.youtube.com/watch?v=8qc_RYm0ylA&NR=1

--
Christopher A. Young
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On Oct 23, 7:38�am, "Stormin Mormon"

griswald is what my neighbor was called reportedly by everyone he knew.
he lit up the neighborhood, and his power bill:( collected donations for salvation army and created sometimes massive traffic jams, after his display was featured on news.
i alwasys expected him to blow the local transformer..........
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Neat. Would have liked to see that, but it sounds dangerous.
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