Delta-Wye Question

kwired said:
I think your real question was probably about running a motor only rated for 230 volts on a 208 supply.

It will work. It will draw roughly 10% more current for same output as it does when supplied from 240 volt supply. Closer you are to loading it to it's rated output the more likely it will be operating beyond it's designed current rating. If it runs for short periods of time, or is seldom to never fully loaded you may never really have any trouble with it. If it runs rather continuously and at/near rated load you may have shorter motor life due to extra heat in the windings.

Motors marked 208-230 volts were intentionally designed to handle the extra current when used on a 208 supply. Also if your 208 supply tends to run a little on the high end of acceptable tolerance - say around 215 volts, you are kind of near the lower acceptable tolerance range of 230 volts and that does help you out a little with how much impact you will have from operating it at a low voltage.
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This 4HP, 230 volt motor powers an airless sprayer. The 480v primary is actually only 458, so the best I'm getting out of the Delta-Wye xfmr is 220V on the secondary. I have a 13KW generator that I will use if the commercial supply proves to be inadequate. It has a fairly sophisticated control circuit that includes over and under-voltage protection and temperature monitoring. I bought it (used) for one job using donated funds and must be able to sell it after the work for the project to stay in budget (a submarine memorial). Maybe I'm being overly cautious, but I do appreciate everyone's input.
 
OldSparks said:
It has a fairly sophisticated control circuit that includes over and under-voltage protection and temperature monitoring. I bought it (used) for one job using donated funds and must be able to sell it after the work for the project to stay in budget (a submarine memorial). Maybe I'm being overly cautious, but I do appreciate everyone's input.
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As I said, the motor coils only see the L-L voltage and can't see the phase angles because the necessary reference is not connected to the motor.

But if the control circuit is monitoring L-N or L-G voltage it will see the phase angles or the strange L-N voltage. If the control circuit expects 120V L-N, it will instead be getting 139V
 
OldSparks said:
I'm getting my you-know-what kicked while trying to post the photo. What's the trick?
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Where is the pic?

If you can see it, try right-clicking, select Copy Image, then in the forum window, right-click and select Paste Image.

If you have a URL, you can copy and paste the link in the button that looks like a dot above the mountains in By URL.
 
LarryFine said:
Where is the pic?

If you can see it, try right-clicking, select Copy Image, then in the forum window, right-click and select Paste Image.

If you have a URL, you can copy and paste the link in the button that looks like a dot above the mountains in By URL.
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I have a photo on my phone (and on my Mac computer).
 
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