Compressor question

[CRittaler]

Hey guys,

I recently acquired a free air compressor and I'm trying to find information on the motor. It says it's a dual voltage motor but I can't figure out how it's supposed to be wired if I want 115V. I don't have 220V in the garage so I would like to swap it over.

I'm hoping that I don't have to pull the whole back half off the motor.

[ArdWrknTrk]

You probably need to remove the wires so you can lift that plastic shield and reconfigure the winding's connections.

You certainly don't need to remove the bell.

2hp is 1500W, so be sure the wire gauge of the cord is up to carrying the doubled amperage you need to run it at 120V.

[ArdWrknTrk]

You probably need to remove the wires so you can lift that plastic shield and reconfigure the winding's connections.

You certainly don't need to remove the bell.

2hp is 1500W, so be sure the wire gauge of the cord is up to carrying the doubled amperage you need to run it at 120V.

By using ohm's law we know IV/R 1500W @ 120V is approximately 12A.

I would probably play it safe and use a 14Ga. cord.

Here is a video explaining the different winding configurations for 240 V 120V

Jeremy is really good at simplifying electric circuits.

And another from Matthias in Canada:.

[CRittaler]

By using ohm's law we know IV/R 1500W @ 120V is approximately 12A.

I would probably play it safe and use a 14Ga. cord.

Here is a video explaining the different winding configurations for 240 V 120V

Jeremy is really good at simplifying electric circuits.

And another from Matthias in Canada:.

Thanks! I knew the coils needed to be changed from series to parallel, I just haven't ever done it on an AC motor. My background is Electrical Engineering, but I specialized in Electromagnetics so I deal with analog, digital and RF circuits, but not so much with the high power AC devices.

With any luck there's a diagram on the back of that plastic cover so I don't have to ohm out each coil.

[ArdWrknTrk]

Thanks! I knew the coils needed to be changed from series to parallel, I just haven't ever done it on an AC motor. My background is Electrical Engineering, but I specialized in Electromagnetics so I deal with analog, digital and RF circuits, but not so much with the high power AC devices.

With any luck there's a diagram on the back of that plastic cover so I don't have to ohm out each coil.

I've always seen a sticker on the inside of the metal cover plate but perhaps it's molded into the insulator.

It really isn't too troublesome to ohm out a few wires, but as noted 'polarity' matters in order to keep things in phase.

[CRittaler]

I've always seen a sticker on the inside of the metal cover plate but perhaps it's molded into the insulator.

It really isn't too troublesome to ohm out a few wires, but as noted 'polarity' matters in order to keep things in phase.

I pulled the plate of the motor last night and there's nothing on it unfortunately.

I just got the 12 gauge extension cord to rewire it so I'm going to dig into it today.

Thanks!

[CRittaler]

I've always seen a sticker on the inside of the metal cover plate but perhaps it's molded into the insulator.

It really isn't too troublesome to ohm out a few wires, but as noted 'polarity' matters in order to keep things in phase.

Looks like I get to enjoy this..

The plate shown in my earlier post is attached to the inside of the back panel. I popped the panel off and can see the windings zip tied up top.

My son woke up from his nap early so I didn't have a chance to meter them out yet.

I may take some time to solder a bleed resistor across the start capacitor while I'm in there.

[ArdWrknTrk]

Looks like I get to enjoy this..

The plate shown in my earlier post is attached to the inside of the back panel. I popped the panel off and can see the windings zip tied up top.

My son woke up from his nap early so I didn't have a chance to meter them out yet.

I may take some time to solder a bleed resistor across the start capacitor while I'm in there.

12A not 12Ga. You could have run it on a 16Ga.. cord...

The metal cover plate you have hanging by one screw in the prior picture says 12A, so it must have come wired 120V

But the line 1 & 2 are reversed from what is shown (If the plug is wired correctly)

I'm astounded that the windings aren't set up with jumper(s) where you can just swap some wires around in the terminal block.

That gob of electrical tape makes it seem someone's been in there.

But it seems you've got the bell off now, so..,...

 

[CRittaler]

12A not 12Ga. You could have run it on a 16Ga.. cord...

The metal cover plate you have hanging by one screw in the prior picture says 12A, so it must have come wired 120V

But the line 1 & 2 are reversed from what is shown (If the plug is wired correctly)

I'm astounded that the windings aren't set up with jumper(s) where you can just swap some wires around in the terminal block.

That gob of electrical tape makes it seem someone's been in there.

But it seems you've got the bell off now, so..,...

I know it only draws 12A, the cord it's on is 16GA, i prefer to over build it. I also went with a longer cord than is on it now.

Once I can get back out there I'm going to pull the front out and check the bearings and look for scoring. Someone has been in it before, the bearings have been replaced with sealed ones.

[CRittaler]

12A not 12Ga. You could have run it on a 16Ga.. cord...

The metal cover plate you have hanging by one screw in the prior picture says 12A, so it must have come wired 120V

But the line 1 & 2 are reversed from what is shown (If the plug is wired correctly)

I'm astounded that the windings aren't set up with jumper(s) where you can just swap some wires around in the terminal block.

That gob of electrical tape makes it seem someone's been in there.

But it seems you've got the bell off now, so..,...

Took the motor completely apart. It's been rewired to a single voltage motor. There are only two windings inside, the main winding and the start winding.

Looks like I'm on the hunt for a dual voltage motor.