Transformer and Panelboard within MCC?

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ElectricNewEngland

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I want to specify a 10KVA transformer and a 110-amp, 12-pole, 120/240V, 1-phase panelboard within a new 480V, 3-phase, Allen-Bradley Motor Control Center. I would like to put both the transformer and panelboard in the same MCC section, if possible. How much space would the transformer and panelboard take up within the MCC? How would I find this info?
I looked on the Allen-Bradley site and I found that a 480V primary to 120/240V secondary 10KVA transformer would use a space factor of 1.5 (which I believe is 18" of vertical space), but it doesn't tell me how much space the panelboard would take up. Please help. Thanks
 
Why worry about spacing. You have to order it anyway, and AB will size the section so both fit. Now if you need to know section sizing and limitations, the best way to get that info is to contact AB sales.
 
To further that, everything that goes into an MCC must be specifically UL 845 listed as part of the MCC, so you cannot specifically dictate the exact size panel that goes in, you will have a selection of sizes and use the one that works.

All that said, I used to be an MCC specialist with Rockwell. An 18 circuit MLO panel (or 16 ckt with MCB) is the smallest available. It will take 2.0 space factors. A 10 kVA single phase transformer is 1.5SF, but you must feed and fuse it from somewhere. The most common way to buy it is to package it with the primary CB feeding it from the bus. That unit, including the CB, is 2.5 space factors. So if you put the panel directly above the transformer as most people do, you will use 4.5 space factors total.

And yes, a Space Factor is 12" nominal.
 
Jraef said:
To further that, everything that goes into an MCC must be specifically UL 845 listed as part of the MCC, so you cannot specifically dictate the exact size panel that goes in, you will have a selection of sizes and use the one that works.

All that said, I used to be an MCC specialist with Rockwell. An 18 circuit MLO panel (or 16 ckt with MCB) is the smallest available. It will take 2.0 space factors. A 10 kVA single phase transformer is 1.5SF, but you must feed and fuse it from somewhere. The most common way to buy it is to package it with the primary CB feeding it from the bus. That unit, including the CB, is 2.5 space factors. So if you put the panel directly above the transformer as most people do, you will use 4.5 space factors total.

And yes, a Space Factor is 12" nominal.
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that sounds about right. they usually eat up about half a section.
 
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