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Discussion Starter · #1 ·
Hi Guys

Are motor current ratings as stated on motor name plates rated for phase or is it the sum of all the three phases ?


If it says in an example

220/380v 50hz 1hp 3.6/2.1 A

Is the (3.6/2.1 A) per phase or the sum of all three ?




Thanks in advance guys :)
 

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Discussion Starter · #4 ·
but the rated current wont be drawn at the same time from the three phases, each phase will have its own period, right ?
 

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IBEW L.U. 1852
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That is technically correct. Each phase will peak to that amperage rating 60 times every second (assuming a 60 HZ supply and no VFD) and each will be 90 deg out of sync with the next.

Its nothing you will ever be able to read with your average clamp on amprobe.:laughing:
 
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that is technically correct. Each phase will peak to that amperage rating 60 times every second (assuming a 60 hz supply and no vfd) and each will be 120 deg out of sync with the next.

Its nothing you will ever be able to read with your average clamp on amprobe.:laughing:
fify
 
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fertilizer distrubuter
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That is technically correct. Each phase will peak to that amperage x 1.44 60 times every second (assuming a 60 HZ supply and no VFD) and each will be 120 deg out of sync with the next.

It's the rms rating and you will able to read it on each phase with your average clamp on amprobe.
fify again.
 
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