Motor Nameplate Multiple Ratings

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bwat

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I have an IEC motor that has multiple power ratings for the same voltage. How is that supposed to be interpreted?

Ex:
3.0 HP, 230V, 9.2A, 3500rpm
3.5 HP, 230V, 10.4A, 3480rpm

Is this almost treated like a service factor? I'm aware that IEC motors do not have this. So treat as 3hp, but it could run at 10.4A and be just fine... understanding that it may shorten the life?
 
I would treat the highest HP as THE nameplate rating with 1.0 SF and call it a day. Unless the manufacturer provides other info.

In actuality, you could take any motor’s curve and pick multiple points to display on the nameplate. No idea why you’d want to do that???
 
bwat said:
I have an IEC motor that has multiple power ratings for the same voltage. How is that supposed to be interpreted?

Ex:
3.0 HP, 230V, 9.2A, 3500rpm
3.5 HP, 230V, 10.4A, 3480rpm

Is this almost treated like a service factor? I'm aware that IEC motors do not have this. So treat as 3hp, but it could run at 10.4A and be just fine... understanding that it may shorten the life?
Click to expand...
If it is IEC it wouldn't be in HP.
 
retirede said:
I would treat the highest HP as THE nameplate rating with 1.0 SF and call it a day. Unless the manufacturer provides other info.

In actuality, you could take any motor’s curve and pick multiple points to display on the nameplate. No idea why you’d want to do that???
Click to expand...
Yeah, that's similarly along the lines of what I was thinking. But I couldn't really figure out why they would do this. If it's a 3.5hp.. call it a 3.5hp. Why list multiple ratings unless there's a caveat to treating it as the higher rating.
 
bwat said:
There are kW values also on that line. 2.2kW (3HP) and 2.64kW (3.5HP). I'll post pic.
Click to expand...
OK. I just haven't seen HP figures for motor kW for years, possibly decades, in my neck of the woods.
 
According to that nameplate, the motor will draw less current on 208 than 230, both at 3 HP?
Now I’m worried!
I see that the power factor is higher at 208, but I’ve still never seen a lower current at 208 than 230.
 
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