Quick Grinder Motor question

[KillerGriller]

I’ve found a 3 phase, 4pole, 200v, induction motor for sale but I can’t find a hp value for it online?

60hz
1410 rpm @200v
1750 rpm @220v

I found a website to give a quick estimate which said ~1/3hp, does that sound right?

 

[Rhinoknives1]

I really can’t answer your question other than I never buy a motor that doesn’t have tin plate on it that states, ————110 or 220 volt, 3500 or 1750 Rpm and a HP rating so I’ll know what the heck I’m buying!

 

[Lieblad]

An experienced motor guy could estimate by seeing its physical construction. Shaft size, wires within its peckerhead, hook up and take electrical measurements, etc.
But there is no way to know without its factory dataplate.

 

[JTknives]

That’s a weird one. Normaly with ac motors rpm is tied to HZ not voltage. You see rpm change with voltage on DC motors. If you drop the voltage on an ac motor by half you reduce HP by a factor of 4.

 

[KillerGriller]

There is a data plate, with everything I gave above, but no hp value.

For clarification, it says;
200v - 50hz - 1410rpm 1.3a
200v - 60hz - 1700rpm 1.2a
220v - 60hz - 1720rpm - 1.2a

Sorry for the confusion

An experienced motor guy could estimate by seeing its physical construction. Shaft size, wires within its peckerhead, hook up and take electrical measurements, etc.
But there is no way to know without its factory dataplate.

Going by the conversion website I found, and info on other motors I’ve seen it looks like 3hp tends to run in the 13amp zone?


Moving on, can you run a 575v motor on a 220v service?

 

[Drew Riley]

Do you have a link or some pics to the motor? There's really no way to tell based on the info given.

 

[KillerGriller]

It’s a Facebook sale, not sure if it’ll be visible

https://www.facebook.com/marketplace/item/2227709627494531/

 

[Drew Riley]

According to the nameplate, it's a .2kw motor. That comes in at around 1/4hp which isn't nearly enough power for a grinder.

 

[KillerGriller]

According to the nameplate, it's a .2kw motor. That comes in at around 1/4hp which isn't nearly enough power for a grinder.

Cheers, thanks for the feedback

 

[Ken H>]

Moving on, can you run a 575v motor on a 220v service?

That depends on how the winding are in the motor. No way to tell from that limited info

 

[KNelson]

Agree with drew, about a 1/4HP which is useless. Voltage and amps relates to a hp rating

 

[KillerGriller]

Agree with drew, about a 1/4HP which is useless. Voltage and amps relates to a hp rating

Agreed, I was hoping a 220v motor would be more likely to have more hp than a 130 furnace motor.

That depends on how the winding are in the motor. No way to tell from that limited info

Hypothetically: If you managed to wire a 120v motor with 220 plug you’d blowup the motor, but what would be the fallout of trying to run a 575v motor on a 220v system?

 

[Lieblad]

but what would be the fallout of trying to run a 575v motor on a 220v system?

It would run at greatly reduced power, and at such reduced power, take forever to get up to speed if at all.

 

[Kevin Kf knives]

Basically, you multiply volts times amps, that gives you watts, then divide by 746, that gives you horsepower, 746 watts is 1 hp.

 

[JTknives]

In an electric motor if you cut the voltage in half you reduce HP by 4 times. So if you ran a 240v 1hp on 120v it would put our 1/4hp. So that 575v motor would put out 10-1/2 times less hp on 220v. If it was 10hp motor you would end up with less then 1hp and it probably would not have enough torque to even get started.