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I have a 3 phase motor with half the nameplate missing

I have a 3 phase motor with half the nameplate missing

(OP)
I am missing the amps value on the nameplate for a 3 phase motor

Values still showing on nameplate;
50hz
kW - 4.4
PF - 0.81
EFF - 84
RPM - 1430

I am in the UK so 230v

Please can someone confirm if 7.87 amps is the correct value to input in the inverter

Thanks thumbsup2

RE: I have a 3 phase motor with half the nameplate missing

you need to get a motor shop involved, they can tell you all you need to know!

RE: I have a 3 phase motor with half the nameplate missing

Something is confusing with: "3 phase motor", "I am in the UK so 230v" and "7.87 amps"!
If the rated voltage (line to line) is 400 V, 50 Hz then the full load Amp is usually 7-9 Amp ( for S1 duty cycle).

@ACWindings

RE: I have a 3 phase motor with half the nameplate missing

Perhaps not all that confusing, as the three phase supply is 400V and the single phase supply taken from one phase and neutral is 230V.

If the OP's intention is to run this 400V motor from a 230V supply using an inverter then the real question is whether this is a 230V Δ / 400V Y motor or a 400V Δ / 690V Y motor. The former can be configured to operate from a 230V supply without much difficulty, although 4.4kW inverters with single phase input aren't all that common. If it's the latter type then there are also options but not as straightforward.

If the motor is configured for operation on 400V and the OP posts a photo of the motor terminals and the position of the links then maybe we could make an educated guess as to which type it is.

RE: I have a 3 phase motor with half the nameplate missing

230 Volts line to neutral = 400 Volts line to line.
4400 Watts / (400 x root 3) = 6.35 Amps.
Real power = 6.35 Amps / .84 (efficiency) = 7.56 Amps
Apparent power = 7.56 Amps / .81 (PF) = 9.3 Amps
But it depends. This is based on assumptions.
The slip is a little higher than normal and the efficiency is a little lower than normal.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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