Hey guys I got this compressor though it calls for 5 horse motor I been using a 1 because I had a bunch but I got this 3 phase and it won't even turn it and also if anyone cares to guess why the air compressor in the pic isn't on all compressors let me know.Im fairly certain the motor has been converted to run 220 I'm just thought it would have little more torqe
3 phase motor maybe weak
- Thread starter jbird5986
- Start date
I'm having a hard time understanding your post, but what the heck kind of set up have you got there?
2 motors driving the pump.
a 3 phase motor will not run on standard household power, unless you have a converter
2 motors driving the pump.
a 3 phase motor will not run on standard household power, unless you have a converter
Snapped-off
Well-known member
jar944
Well-known member
You need 3 phase power for a 3phase motor to work.
dual voltage is not the same as a single phase or 3 phase motor.
and as already mentioned at least 2 times, a 3 phase motor, which you have shown, will not run on single phase..., which is probably what you're trying to hook up to
jar944
Well-known member
As long as either is 460v 3phase or 240v 3phase.
Well that explains it although its been on a fan for months running but it doesnt require near the torque as that compressor does thats why i swing a hammer but im nearly positive ive used them before but then again i used to drink a little back then.
WillyBoy
Well-known member
A two row pulley on the compressor doesn't mean that there should be two motors powering it.
It indicates that the motor, whatever motor you find that works, should have a two row pulley and two belts to the compressor.
It indicates that the motor, whatever motor you find that works, should have a two row pulley and two belts to the compressor.
Actually a 3 phase motor will "run" on single phase power. However it won't start nor develop full power. I sometimes test them on single phase. Give them a manual spin and they go.
As for that compressor setup it's a kludge.
jar944
Well-known member
Fair, and I agree.
However I didn't think he wanted to pull start it and only have 2/3 the hp
Maybe his first motor would start the 3 phase motor.
wyliesdiesels
Well-known member
you were doing whats called single phasing the motor, running it on only 2 legs which can overheat and burn up the motor.
as said above, you need 3 phase power or a converter/VFD to run that motor.
also please put some guards on those belts.... and its pointless to power a compressor with 2 motors like that....
wyliesdiesels
Well-known member
yup. its called single phasing and it will burn up the motor.
MBfreak
MEMBER EMERITUS
A swedish nuclear power station had one( out of 4) 3 phase 10 kV networks single phase due to a faulty incomer CB ( 1982 vintage)
Three phase motor load 26 MW, from 150 kW to 2 MW units.
All overheated in less than 3 minutes and were scrapped.
As was the feeding 25/10,7 kV 36 MVA transformer
Ola
Ola
Three phase motor load 26 MW, from 150 kW to 2 MW units.
All overheated in less than 3 minutes and were scrapped.
As was the feeding 25/10,7 kV 36 MVA transformer
Ola
Ola
Oregon rock crusher
Well-known member
Besides the three phase motor not providing any tourque while only hooked up to single phase it is very difficult to get two motors of any type to work together driving anything. Even small differences in rpm will make them fight each other causing either belt slip or over heating. Even with matched motors, new shives, and new belts it is best to start one first and bring the second up to speed before starting it. That is unlikely on an intermittent load like an air compressor. Ed.
Cruzan80
Well-known member
Less torque, not no torque. Once it is spinning, it does develop some torque, but less than nameplate. Whether it is enough is a different question
A.K.A. - single phasing
Cruzan80
Well-known member
Why do you feel you need a 10hp motor? Do you have the power to supply a 10hp motor (even de-rated)?
That's what I was going to bring up as it looks as if the two pulleys are not the same diameter. Also: two different motors from 2 very different designs are not likely to have exactly the same RPM (2 pole vs. 3) so the smaller motor in the pair will not be running at locked rotor RPM and will soon overheat. On top of all that, it looks like a capacitor zip tied to the 3ph??