# 3-phase amp draw



## mocitytx (Aug 30, 2011)

If you have a 3-phase motor, is the amp draw the same on all three phases? For example a 5 Hp motor (3.73 KW) on 230V would draw 16.2A if it was a single phase motor. If the motor is 3-phase, would each phase see 16.2A or 5.4A each (assuming that the 3-phase voltage is also 230V)?


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## Zog (Apr 15, 2009)

Welcome to the forum. Your profile says you are an engineer? This sounds like a homework question to me.


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## mocitytx (Aug 30, 2011)

Didn't say I was an electrical engineer.


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## CraigV (May 12, 2011)

Choo-choo!!!!! :lol:


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## alpha3236 (May 30, 2010)

Divide the single phase amperage by 1.732 (sq. root of 3) to get 3 phase numbers and yes the amperage is the same on all 3 legs in theory. In practice there is usually a slight imbalance due a number of physical factors.


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## acro (May 3, 2011)

This



alpha3236 said:


> In practice there is usually a slight imbalance due a number of physical factors.


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## wingz (Mar 21, 2009)

5 HP 230v single phase motor is calculated at 28 amps, T430.248.

3 phase is 15.2 amps, T430.250.


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