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Old 08-18-2012, 08:20 PM   #1
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My main breaker box is 200A. If have a 100A subpanel box installed, is that subtracted from the 200A main or inaddition to it?

If it subtracts from the main box, effectively leaving me with two 100A boxes, is there a way to install an independent 100A box to the main power line coming into the house?

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Old 08-18-2012, 08:54 PM   #2
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My main breaker box is 200A. If have a 100A subpanel box installed, is that subtracted from the 200A main or inaddition to it?

If it subtracts from the main box, effectively leaving me with two 100A boxes, is there a way to install an independent 100A box to the main power line coming into the house?
No. It is based on the calculated load.

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Old 08-18-2012, 08:54 PM   #3
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calculated off of what?
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Old 08-18-2012, 09:00 PM   #4
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calculated off of what?
The load of the building, and the NEC tells us how to calculate this.
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Old 08-18-2012, 09:04 PM   #5
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Ok, so I have a load coming in on the main line that may or may not be maxed out by the main box....

Is this an easy quick test that can be done on a normal call?
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Old 08-18-2012, 09:05 PM   #6
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Ok, so I have a load coming in on the main line that may or may not be maxed out by the main box....

Is this an easy quick test that can be done on a normal call?
What are you trying to do, exactly?
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Old 08-18-2012, 09:11 PM   #7
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I need/want a controller for some receptacles for my christmas lights.

Last year I was working off of 80A from numerous receptacles outside and in the garage. I would like to have the receptacles used for these lights centrally located and on a timer.

A couple of things I'm considering is a subpanel or a 240 outlet where a custom light controller would plug in.
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Old 08-18-2012, 09:13 PM   #8
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I need/want a controller for some receptacles for my christmas lights.

Last year I was working off of 80A from numerous receptacles outside and in the garage. I would like to have the receptacles used for these lights centrally located and on a timer.

A couple of things I'm considering is a subpanel or a 240 outlet where a custom light controller would plug in.
You wouldn't be able to afford a 80 amp load... you'll be fine.
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Old 08-18-2012, 09:17 PM   #9
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You wouldn't be able to afford a 80 amp load... you'll be fine.

I'm not following...

Last year I had 35k lights on 4 20A circuits and they were all pretty much maxed out. And this year I'm looking at 50k - 75k lights

The main reason is to have everything run out of one box for timing issues.
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Old 08-18-2012, 09:19 PM   #10
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I'm not following...

Last year I had 35k lights on 4 20A circuits and they were all pretty much maxed out. And this year I'm looking at 50k - 75k lights

The main reason is to have everything run out of one box for timing issues.
How did you come up with the actual loads? and what was your electric bill?
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Old 08-18-2012, 09:20 PM   #11
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You would have to bring individual branch circuits to a lighting controller...whether it be from a main panel, a sub, or both. You cannot plug in a lighting controller to a larger 240V circuit.
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Old 08-18-2012, 09:23 PM   #12
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How did you come up with the actual loads? and what was your electric bill?
My neighbors cousin is an apprentice and he had a load meter or something that measured the draw (i think that's what he called it) at the box.

Each circuit was drawing 18A - 19A.

They don't cost me too much. The lights are only on from 5pm to 10pm, but there is an obvious increase in my consumption for the month.
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Old 08-18-2012, 09:26 PM   #13
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You would have to bring individual branch circuits to a lighting controller...whether it be from a main panel, a sub, or both. You cannot plug in a lighting controller to a larger 240V circuit.
The box is basically a subpanel but not permanent. It contains individual circuits for each receptacle.

These are the type of boxes I was looking at.

http://www.dxsoundco.com/#Lighting_Controllers
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Old 08-18-2012, 09:29 PM   #14
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Yeah, that is not legal in any way, shape, or form.
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Old 08-18-2012, 09:31 PM   #15
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Yeah, that is not legal in any way, shape, or form.
I concur...

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