How much HP is this compressor motor?

[tkent02]

My pump fried, need a new one. I would get a bigger pump if the motor is big enough. The compressor says 6.5HP on the tank, but I think that's Pure BS, peak HP at startup or some other false advertising.




It's just a 3 or 4 HP motor, isn't it?

[tatu]

seems like an unusual thing to do, what is your supply voltage, I thought the States was 110, your motor there is 208/230v supply

[tkent02]

Yes, it is 220 Volt.

[tatu]

Its a 5hp motor, motors last forever, does the pressure line vent between start ups (hysteresis) so it starts off load?

[tkent02]

Are you sure? I looked at a five horsepower motor, it was listed at 22 amps

[tom203]

On a good day, that motor is maybe 2 hp- single phase motors make all sorts of silly hp claims, sometimes they call it "peak" hp. Basically, a real efficient 1 hp motor would draw 7.5 amps running on 208/230 sigle phase supply,2 hp would draw 15 amps,etc

[rustybronco]

Tom, as you have rightfully guessed, they play fast and loose with the H.P. numbers.
My compressor states that it comes with a 6 H.P. motor. Fat chance on that number being correct. IIRC it draws around 15A as well. I'd look for a higher Amperage rated motor.

Are you sure the motor is fried? It could have a bad start cap, stuck centrifugal switch or bad start contacts. Just because it hums doesn't mean its bad. Or, did smoke roll out of it?

[tatu]

On a good day, that motor is maybe 2 hp- single phase motors make all sorts of silly hp claims, sometimes they call it "peak" hp. Basically, a real efficient 1 hp motor would draw 7.5 amps running on 208/230 sigle phase supply,2 hp would draw 15 amps,etc

Yes this sounds better, sorry. Do you know whats caused the motor to burn out?

[tkent02]

No, the motor is fine, the pump siezed up. Replacing it. HF sells a 3hp and a 5 hp pump. Ill try the 3.
Unless i hear something different.
Thanks.

[rustybronco]

seems like an unusual thing to do, what is your supply voltage, I thought the States was 110, your motor there is 208/230v supply

Chris, we use center tapped transformers to supply power to our homes. One leg to the neutral gives 115V, across both legs gives 230V.

[tatu]

Chris, we use center tapped transformers to supply power to our homes. One leg to the neutral gives 115V, across both legs gives 230V.

Ok, got it thanks.

No, the motor is fine, the pump seized up. Replacing it. HF sells a 3hp and a 5 hp pump. Ill try the 3.
Unless i hear something different.
Thanks.

Is it belt drive? if so would it be possible to find a refrigeration unit from an aircon?
When I was a young lad I used an ordinary sealed unit from an ordinary household fridge, I understand in the US you have big fridges maybe that would be the way to go, using your tank, bin the rest and stick on a sealed unit. You will sure pick one'v those up for free and those go on forever. Oh, and silent running.

[JTGS850GL]

Specs say it's a 15 amp motor. That would make it around a 3HP motor at 220V.

[rustybronco]

Tom, can you get a larger air pump and change the pulley on the motor so the motor can handle the increased displacement (under driving it) without having to resort to buying a new pump and a larger motor?

[tkent02]

I thought of that, but a big pump running slower probably isn't any better than the smaller pump at it's designed speed. Just bought a pump made for 3hp motor, the displacement is 18% smaller than the old one so it will work with the old motor, if a bit slow at pumping. Got work to do, can't mess around with it forever.

Thanks for your help.