# Thread: MI PSI Practice Exam Question

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Q: What is the motor nameplate FLA rating ...
There is no way to mathematically answer this question.
The correct answer can only be found by physically looking at the motor's Nameplate FLA.

The code FLA current is found by looking in the NEC.
The theoretical FLA have already been discussed in post #2.

2. I would guess that they asked for nameplate so you wouldn't use a table in the NEC and perform the calculation in post #2.

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Originally Posted by infinity
I would guess that they asked for nameplate so you wouldn't use a table in the NEC and perform the calculation in post #2.

The NEC does talk specifically about using the FLA on the nameplate when sizing running overload protection. Nameplate information is not found anywhere but on the motor.
It appears the question is looking for the calculated running amps of the specified motor.

4. Originally Posted by jim dungar
I agree poor question but I think that many here could find the answer they were looking for using Besoeker's method.

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## correction

sorry, (h.p.x746)

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conductor size and short circuit and ground fault protection is based on FLC, overload is based on nameplate FLA.
The formula for FLA is (h.p.x746)/(ExEFFxPF). They just want you to know that the FLA is based upon motor ratings and do not truly indicate actual load of motor.
430.6(a)(1)
430.(52)(c)(1)

overload-430.6(a)(2) based on nameplate. FLC=Code, FLA= Actual nameplate.

7. Originally Posted by infinity
I agree poor question but I think that many here could find the answer they were looking for using Besoeker's method.

I agree.. Bes nailed it. and we are trying to make it more complicated than it is. Test question are generally not perfect.

Texie the test question was looking for a nameplate amps not the NEC code requirement.

8. Originally Posted by K8MHZ
I just Googled a couple 5hp motors and checked the nameplates. One had an FLA of 22, the other 25 at 230 volts.

Besoeker's math makes total sense to me. I don't understand where the NEC came up with 28 amps.
Thank you kindly.
Just arithmetic.

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