Okay to use 120/240 VAC Panel and Switch for 120/208 VAC system?

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ItsFriday and I need to get an order out before the holiday week and I don't havethe time to check my textbooks. I'm was ordering parts for a 120/240 VAC 3 wiresystem

--SQUARE D panel NQ18L1-PNLBD INT NQ 100A MLO 18CKT 1P
--ALD223NRB SWITCH FUSIBLE GD 240V 100A 2P NEMA3R

and then I discovered I had a 120/208 system. I can still usethese right? I only need the 120 VAC not the 240 VAC.
Thanks, I'm hoping to get out of the office on time
 
Clarification

Clarification

The Panel upstream is a 120/208 VAC 3 phase but out on the field , I'm replacing a panel with only single phase 120 VAC circuits.
I was told it was 120 /240 VAC upstream
I wanted to verify everything and to my surprise I found the upstream Panel Drawing this morning and its 120/208 VAC 3 phase.
I only need 120 VAC, not the 208. I'm going to do this right and cancel the order
 
I do not know of a code violation that would prohibit you from feeding a 2 phase panel from a 3 phase system -- a lot of OCPD are rated as multi voltages -- if your equipment is rated higher than what is existing what would be the issue?
 
You are still under the 240 volt rating of the equipment. They don't make any that are only rated for 208 volts. You might get factory assembled unit that is marked with 208/120 but it is made from same components as the stocked 120/240 items.

Your only other choices from Square D is to go with a NF panelboard, rated for 277/480 but 120/208 is still less then that and will work with that series also, or go to the I line series - which you can get up to 600 volt rated breakers for.
 
I'm pretty rusty

I'm pretty rusty

I thought it through, its all okay. I'm pretty rusty, that's all. I can jumper the second leg of the Panel from the first and all you will get from is 18 120 VAC circuits Thanks for your replies. I made the order
 
Installer said:
I thought it through, its all okay. I'm pretty rusty, that's all. I can jumper the second leg of the Panel from the first and all you will get from is 18 120 VAC circuits Thanks for your replies. I made the order
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Why do you want to do that? Not only does it unbalance your three phase supply more so then if you ran two "phases" plus neutral but now with 100 amp supply conductors - you are limited to 100 x 120 = 12,000 VA total load. If you ran two phases plus neutral you still have 120 volts on all 18 spaces but with 100 amp supply conductors can supply 24,000 VA of 120 volt load, you have less voltage drop issues with the feeder, you unbalance the three phase supply less severely, and do have 208 available should something come up where it is needed. You also are likely going to have a 2 pole breaker for the feeder either way because it is likely difficult if not impossible to find a 100 amp single pole for whatever you are supplying it from.
 
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