Induction motor calcs.

Discussion in 'General Electronics Chat' started by Superheterodyne, Jan 27, 2012.

1. Superheterodyne Thread Starter New Member

Jan 27, 2012
1
0
Hello and greetings.

I wonder if anyone Might know how to derive the breaker size from details stamped on the motor plate.

The motor in question is a single phase 230v model.

The only available information on this plate is;

13.3 Ampere
2.2 Kw *output*!? What - is this horsepower?

That's it.

The fella' that rewound the motor said it will pull 60 amps on startup.
How can the breaker size etc be gleaned from this sparse info.

2. mik3 Senior Member

Feb 4, 2008
4,846
63
Assuming a PF of 0.65, the current drawn by the motor equals:

$I=\frac{P}{V*PF}=\frac{2200}{230*0.65}=14.72A$

1HP equals 0.745kW, thus 2.2kW equal 3HP.

You will need a 20Amp rated braker.

Last edited: Jan 27, 2012
3. GetDeviceInfo Senior Member

Jun 7, 2009
1,571
230
easy, you go to your code book, lookup the breaker size. The CEC lists a maximum breaker size of 250% FLA.