Anybody know bout electric??

[FarmboyBill]

I have a air compressor that I bought at the sale. It has a motor that blew out my switches in the house, so I bought a plug the same as my welder. When I plugged it into that, it threw the breaker quicker than the welder. It is the type that has one wheel inbetween 2 tanks. The breaker out there was a 30amp. I thought that was about the biggest there is. Any thoughts.

[Old Vet]

The problem is that your motor pulls too much currant. This may be from a big motor, bad condenser, or the windings may be bad. There is not much to do but to take it to a motor repairman and see or buy a new one and install it. You can go up to 200 amps on a breaker but not recommended 30 amps will run most any motor. On my welder I run 40 amps.

[VOR.]

I don't think a bigger breaker is the answer. Usually when an electric motor goes bad it will throw the breaker as you described.

[Sawmill Jim]

Put it on a big enough breaker you may let the blue smoke out of it Long small wire power cords don't work good either .Old code here was 6/2 wg 60 a dp breaker .

[Iddee]

Quit guessing. It's dangerous. Look at the label on the motor. It will tell you the amps. If it's less than 30, you have a bad motor or cord going to the motor.

[agmantoo]

Is this a belt driven unit? If not and it is a direct drive compressor the compressor could be defective. If belt driven, remove the belt to see if the unit will run. If it runs then disconnect the discharge line from the compressor to the tank at the compressor. It could be that you have either air or oil trapped in the line and the compressor is trying to start loaded.

[Harry Chickpea]

You could have 120 volt, or 240 volt, or three phase. Read the plate on the motor. 1 hp = about 750 watts. A 5 hp motor (fairly common) would take over 30 amps at 120 volts.

[Jim-mi]

Perhaps you got it cheap because the previous owner knew the motor had taken a dump and it was going to be costly to fix . . . ??

[rambler]

Originally Posted by FarmBoyBill

I have a air compressor that I bought at the sale. It has a motor that blew out my switches in the house, so I bought a plug the same as my welder. When I plugged it into that, it threw the breaker quicker than the welder. It is the type that has one wheel inbetween 2 tanks. The breaker out there was a 30amp. I thought that was about the biggest there is. Any thoughts.

Electrical stuff is kinda complicated to do it right, and has a lot of little details that are important.

You blew out switches in the house????? (Do you mean fuses/ breakers???)

You bought a welder plug to put on the compressor. (You haven't said it was a 120, 240, or 3phase compressor - all are common, what do you have???? Was the welder a 120 or 240 welder? Not nearly enough info!)

Common breakers are 15, 20, 30, 40, 50, 60, 100, and 200. There are others.

These breakers do _NOT_ protect your compressor or your welder. The breaker protects the wire running through the walls. The breaker is sized to what the wires can handle.

Often it is real nice to have breaker that also is sized to the device you have plugged into it; but the breaker is really there to protect the wires from melting.

We need a lot more info to understand the problem. Look at the plate on the motor and tell us the phase (1 or 3) and the voltage (common for 120 or 240 to be possible on small/mid sized motors, then you have to look at the way the wires are connected inside the box). What hp is it, so we get an idea of what size we are talking about. 5hp would be about 30 amp.

I'm sure you are working on this right; but with the info you supplied, it's kinda scary what you could actually be doing wrong! Be safe.

--->Paul

[Oldcountryboy]

I'm assuming that when you said it blew out the switches you ment either the breakers or fuses as someone mentioned? If so, did it immediately blow the fuse/breaker, or was there a little bit of a delay before thew were blown?

If it was immediately then you might have a short somewhere. Either in the motor, the cord, or the male plug in.

If there was a delay between the time you turned it on and when the fuse/breaker is blowing, then you might have a overload problem. Which means either your breaker isn't big enough or there's too many things running off that same circuit consuming too much power already.

[ElectricVette]

Sounds like you've got a short. Either the wiring is damaged or the motor is bad. You can do a visual inspection on the wiring by disconnecting from the power source and physically checking the connections at the pressure switch, the motor and junction box if one is on the unit. Look for bare wires or strands touching anything other than the connector they are attached to. Also inspect the cord closely for damage.

If you find nothing from above you've either got a shorted capacitor (you can't always visually see this) or a shorted motor. You can pull the capacitor out and take it to an electrical contractor who can check it for you.

If its not the wiring or the capacitor then likely its the motor which can cost several hundred dollars depending on size and type.

EV