Panelboard or Switchboard?

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dahualin

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I am doing a project with 208Y/120 volt 3-phase 1200 amps service. I am thinking what kind of electrical board I can used for the power distribution system. From manufacturer's catalog, panelboard can be rated 1200 amps with 1200 amps main breaker, switchboard is rated through 4000 amps. Panelboard is definitely smaller and main breaker and branch circuit breakers are integrated into one panel. Switchboard will have at least two sections, one is main breaker section and the other is distribution section. Can I use a panelboard with 1200 amps main breaker as service disconnect means, or I have to use a switchboard? Why? What is the difference between them? How do you approach this power distribution system?

Thanks.

David
 
As long as the voltage, short circuit, and other ratings are available that meet your requirements, there is nothing that says you must use one over the other. Where it may help you, is in deciding how it will be used. To utilize 1200A, I assume you will be using some distribution panels. Therefore, keep in mind that most panelboards are designed to take up at least 6 spaces (3 on each side) for large frame (amp) breakers. This could eat up your breaker space in the main panel pretty quick, or depending on what size distribution power you need, the breakers may not fit in that panel. Otherwise, use whatever fits your needs.
 
Good advice. To add: make sure you don't have an actual load of 1200 amps (80% of which is 960), and keep possible future additions in mind.

(Edited ~ see below)
 
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LarryFine said:
Good advice. To add: make sure you don't have an actual load of 1200 amps (80% of which is 9600), and keep possible future additions in mind.
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I am guessing you mean 960 amps? ;)

But to be accurate a typical 1200 amp service can be loaded up to 1200 amps non-continuous and 960 continuous.

Future loads are a design issue not an NEC issue.
 
If you decide to go with a panelboard, make sure it's "service entrance" rated. Also check with your local Utility as to what requirements they have for metering and/or pullsections.
 
Thanks for your advice.
I did the load calculation for the building based on commercial calculations. All continuous loads have been multiplied with 125%. The total calculated load is 961 amps (208 volts 3 phase) plus 20% for future addition (192 amps). It will be 1153 amps. That is why I need a 1200 amps service.

David
 
I would go with the panelboard since it will cost considerably less. Also don't forget that at 1200 amps the requirements for large equipment kick in. These are outlined in 110.26(C)(2).
 
infinity said:
I would go with the panelboard since it will cost considerably less. Also don't forget that at 1200 amps the requirements for large equipment kick in. These are outlined in 110.26(C)(2).
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Given that and the fact you may be into GFP territory you may want to go with multiple smaller service disconnects.
 
Since I have enough space to cover the large equipment requirement mentioned at 110.26.(C).(2), I am not going to do multiple smaller service disconnects. Here comes another question, can we do multiple smaller services to this building? Refer to 230.2, a building or other structure served shall be supplied by only one service unless permitted in 230.2 (A) through (D).

Any comments are welcome.

David
 
iwire said:
Given that and the fact you may be into GFP territory you may want to go with multiple smaller service disconnects.
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To get around the double clearance issue and GFP issue is it that much cheaper to provide multiple 600A panelboards instead of (1) 1200A switchboard? I would think it wouldn't since now you have to provide multiple runs of service feeders.
 
necnotevenclose,

2, 600a

or

1, 1200a

service,where are the extra conductors?

Now compare $$$ of 1200a/GFP vs. (2) 600a ,that's what we're talking about
 
benaround said:
necnotevenclose,

2, 600a

or

1, 1200a

service,where are the extra conductors?

Now compare $$$ of 1200a/GFP vs. (2) 600a ,that's what we're talking about
Click to expand...

Yeah that's what I meant. That's the ticket. I could imagine installing (2) 600A would be alot cheaper. Thanks.
 
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