Load capacity of 200-amp panel

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You shouldnt have more than 160 amps on any one leg or 80% of 200..
Jimmie
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JIMMIE wrote:

As Doug has probably been saying, the 80% limit is for continuous loads (over 3 hours). Major loads in a house are not likely continuous. A circuit breaker can operate at its full capacity, but may trip if at full capacity for over 3 hours.
--
bud--

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Its doubtfull you would ever pull more than 100 amps on a house wired with a 200 amp panel. Worse case in my house would be WELDER, HVAC, OVEN, and SPA running all at once. Of course if wife and daughter are both doing their hair at the same time that may put me over the top.
Jimmie
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Exactly. So why do you keep talking about the 80% rule? It doesn't apply.

Do they take three hours to dry their hair? While the welder, HVAC, oven and spa are all running? For three hours?
The 80% rule applies _only_ to continuous loads -- which is clearly and specifically defined in the Code.
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On Oct 23, 10:34 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

At the time I read it a continuous power situation is the only thing that made sense to me. Having the flu and taking codeine will change ones sense quite a bit. Sorry, you are correct.
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On Oct 23, 10:34 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

It seemed like it should in this case per the OP's description . What's he doing, growing pot in his attic? Even if technically an installation is residential commercial rules should apply if the situation warrants it. I would say the described situation could fit such a case.
Jimmie
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Incorrect. You do not understand the "80% rule". The rule applies only to "continuous loads" which is defined by the Code as maximum current for a period of three hours or more.
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JayB wrote:

Do you expect to actually draw 200 amps at once, or are you adding up the amperage value of all the circuit breakers?
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The answer is obvious; 200 amps. Although one working current recommendation is to not exceed (I guess that's at any one time) some 80% of the maximum capacity. So say 160 amps.
It's rather like saying how many passengers can a 60 seater bus carry (seated of course)!
The wire connections, bus bars (to which the individual circuit breakers attach) are rated for 200 amps. Do not exceed. BTW 200 amps at 230 volts is 230 x 200 = 46,000 watts (46 kilowatts).And 80% of that is about 37 kilowatts. That's usually plenty for all but the biggest homes. To get maximum capability that load should be balanced over the two 115 volt legs. Because if all the loads were on only one leg the maximum capacity would be 115 x 200 = 23,000 watts (23 kilowatts) and 80% of that is about 18 -19 kilowatts.
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terry wrote:

The answer is obvious; 400 amps.

Don't know about Canada, but in the US 80% only applies to "continuous loads" (over 3 hours). In a house service, if you could get a 200 amp peak it wouldn't last long. Loads cycle on and off. It is called "diversity". Because of diversity the service wires (in the US) can usually be 'undersized' with a residential derate. Can't do that in commercial, where you turn on lights and they are on all day long ("continuous").

And when you balance the load over the two 115 volt legs you get - lets see - 46,000 watts divided by 115 volts - um - 400 amps of 115 volt load. Even in Canada. That is what the OP asked.
--
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Thanks all. I thought I replied back sooner but I don't see my reply anywhere.
I did get the answer to my question here before the converastion drifted off into whatever.
JayB wrote:

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On Thursday, October 22, 2009 at 11:02:51 AM UTC-5, JayB wrote:

DON'T DO IT!
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On Friday, June 24, 2016 at 7:41:07 PM UTC-4, snipped-for-privacy@gmail.com wrote:

Don't do what? A 200 amp panel will support 240V at 200 amps or 400 amps at 120V.
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"trader_4" wrote in message wrote:

Don't do what? A 200 amp panel will support 240V at 200 amps or 400 amps at 120V.
200 amps. is 200 if is 120 or 240, You can not change Amperage Voltage yes Amperage "NO" for 240 Volt max. is 200 amps./leg Each "leg" of 120 Volt, will give max. 200 amps. assuming that neutral is rated for 400 amps.
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On Saturday, June 25, 2016 at 1:50:11 PM UTC-4, Tony944 wrote:

Sigh. Do we have to go through this all over again? A service rated at 240V, 200A will support a load of 240V, 200A or a balanced load of 120V, 400A. Yes the current in the service conductors never exceeds 200A, but if you have 200A flowing through one leg through 200A of 120V loads, through another 200A of 120V loads, and then back out the other leg, it's handling 400A of 120V loads.
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"trader_4" wrote in message wrote:

Sigh. Do we have to go through this all over again? A service rated at 240V, 200A will support a load of 240V, 200A or a balanced load of 120V, 400A. Yes the current in the service conductors never exceeds 200A, but if you have 200A flowing through one leg through 200A of 120V loads, through another 200A of 120V loads, and then back out the other leg, it's handling 400A of 120V loads.
Dear Sir you look at it your way and I will look at it my way. have nice day
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The point is the neutral only handles the unbalanced load between the 2 ungrounded conductors and is they were both pulling equal amounts, the current in the neutral is zero.
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On 06/25/2016 06:01 PM, snipped-for-privacy@aol.com wrote:
[snip]

In other words there is 200A here (one ungrounded conductor) and 200A there (the other ungrounded conductor) and 0A (the difference between the two, never more than 200A) in the grounded conductor. NEVER 400A anywhere.
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wrote:

Yes, on single phase that is true. On 3 phase wye, you can get triplin harmonics that may have the neutral carrying more current that simple math might predict. That happens with reactive loads like solid state flourescent ballasts and PC power supplies. That would need to be the main part of the load to become a problem.
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On Sat, 25 Jun 2016 22:28:14 -0400, snipped-for-privacy@aol.com wrote:

volt service. (It would be 208 in most cases)
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