so uh... sparks flew...

[ureside]

I have this 220 air compressor, that always had a 110 plug on it (not the original) and we'd plug that into a junction box type thing that had a 220 plug on the end of it. Well.... long story short, i finally changed the plug on the air compressor to a 220 plug. Plugged it in the wall where the dryer was... and POP!
it blew sparks and scared the **** out of me, right at the receptacle in the wall. what the hell is wrong here!?
I know i wired the compressor correctly, with a 3 prong 220 plug, and the outside 2 wires went to the positive, and the middle wire went to the negative, there was no ground.
Oh... and now the dryer obviously doesn't work in that plug either

...and it never flipped any switches

 

[bmwpower]

I think you're switching terms here...

There are 2 HOTS and 1 GROUND on a 220v connection.

What color wire was this "negative" wire you connected on the compressor plug?

What color wires were the "positive" wires you connected on the compressor plug?

 

[ureside]

I think you're switching terms here...

There are 2 HOTS and 1 GROUND on a 220v connection.

What color wire was this "negative" wire you connected on the compressor plug?

What color wires were the "positive" wires you connected on the compressor plug?

well i think i figured it out. I had two posts i didn't realize were line in. I took the two hots and put them together, then the one neutral and put it on the other post. Thats why the .

Anyway, saw you race bmw's, i just went ax'ing with the LSCBMW club here in north texas, GREAT group of guys, my 1st AX experience, i'm hooked!

 

[bmwpower]

Assuming the receptacle and compressor motor are wired correctly, you want one hot on each "side" post and the ground on the middle "post". No neutral.

 

[ureside]

Assuming the receptacle and compressor motor are wired correctly, you want one hot on each "side" post and the ground on the middle "post". No neutral.

http://forums.corvetteforum.com/showthread.php?t=1541024 this is what i just went through, you can skim through it pretty easily. I'm 5W0P3

 

[bmwpower]

The CENTER gray wire is a GROUND wire on the plug. Connect it to the green ground screw on the compressor hookup.

Connect each of the other gray wires to one of the LINE connections - ONE to each screw on the compressor hookup.

By placing the center gray wire on the LINE hookup, you essentially grounded the system... not good.

BTW, don't listen to that guy in the thread (knight37128) - he needs to revamp his electrical skills. Never leave the ground wire disconnected...especially in a 220v system.

 

[ureside]

The CENTER gray wire is a GROUND wire on the plug. Connect it to the green ground screw on the compressor hookup.

Connect each of the other gray wires to one of the LINE connections - ONE to each screw on the compressor hookup.

By placing the center gray wire on the LINE hookup, you essentially grounded the system... not good.

BTW, don't listen to that guy in the thread.

which guy? this is how i have it done now... (you have a nice garage btw)

 

[bmwpower]

Correct-amundo.

Thanks for the compliment.

See guy to avoid in my edited post above...

 

[ureside]

Correct-amundo.

Thanks for the compliment.

See guy to avoid in my edited post above...

Gotcha... Thanks, i appreciate the 2nd or 3rd opinion! Maybe i'll have compressed air tommorow now!

 

[thefairlaneman]

I think you're switching terms here...

There are 2 HOTS and 1 GROUND on a 220v connection.

What color wire was this "negative" wire you connected on the compressor plug?

What color wires were the "positive" wires you connected on the compressor plug?

I thought that a 220 cable had 2 hots and a "common" the fouth wire used in many 220 applications is considered the ground. true you can use the third wire a a ground but then the unit you are running will not be "grounded" Help understand if this is wrong

 

[Charles (in GA)]

Standard 20 amp and 30 amp, 240V plugs and receptacles, do NOT use a neutral. They use two hots and a green earth ground. Indeed, the newer standard for dryer and stove receptacles use four wires, the two hots a neutral, and the ground.

Charles

 

[TNToy]

But you only need the neutral wire if you have a reason for that appliance to pull 110V. Some dryers and other 220v appliances have timers and whatnot that actually run on 110v.

A 220V air compressor has no use for 110V, so the neutral is not needed, just the ground.

The two hot wires come from the two hot busses in your breaker box: If you look at where the breaker for 220 clips in, it actually hooks to BOTH of the rails running down the center of the breaker box.

Touch a voltmeter to one of the hot wires and the neutral, and you get 110v. Touch it between the two hot wires, which are 180* out of phase, and you get 220V.

Now if we try to explain why in some cases neutral and ground seem to be interchangeable in newer houses, your head will REALLY start to hurt.

 

[GTS225]

I have this 220 air compressor, that always had a 110 plug on it (not the original) and we'd plug that into a junction box type thing that had a 220 plug on the end of it. Well.... long story short, i finally changed the plug on the air compressor to a 220 plug. Plugged it in the wall where the dryer was... and POP!
it blew sparks and scared the **** out of me, right at the receptacle in the wall. what the hell is wrong here!?
I know i wired the compressor correctly, with a 3 prong 220 plug, and the outside 2 wires went to the positive, and the middle wire went to the negative, there was no ground.
Oh... and now the dryer obviously doesn't work in that plug either
...and it never flipped any switches

********************************************************
This bothers me a bit. Are you saying that the compressor ran fine with a 110/120V plug on the cord? The only thing you did was change the plug on the cord? If so, I suggest you check out the wiring at the motor j-box. Most motors have to have their leads changed around when going from 110 to 220. There should be a wiring diagram somewhere close to the motor data plate for correct hookup.
As for the dryer not working in that plug, I suggest you shut the breaker off to that outlet and change out the outlet. You may have burned something up in there that is keeping your dryer from getting energized, or it may be as simple as a broken wire.

In any case, use all safety precautions.

(BTW....for what it's worth, I am an industrial maintenance electrician.)

Roger

 

[ureside]

********************************************************
This bothers me a bit. Are you saying that the compressor ran fine with a 110/120V plug on the cord? The only thing you did was change the plug on the cord? If so, I suggest you check out the wiring at the motor j-box. Most motors have to have their leads changed around when going from 110 to 220. There should be a wiring diagram somewhere close to the motor data plate for correct hookup.
As for the dryer not working in that plug, I suggest you shut the breaker off to that outlet and change out the outlet. You may have burned something up in there that is keeping your dryer from getting energized, or it may be as simple as a broken wire.

In any case, use all safety precautions.

(BTW....for what it's worth, I am an industrial maintenance electrician.)

Roger

ok, i fixed it today, just melted some metal in the receptacle, put a new one in it. The breaker DID flip, so thats good. Everything is working GREAT now! I'm very happy.

It never ran correctly on 110. just started and then stopped.

 

[goodwrench]

this is not directed at the poster, just to all in general, when it comes to wireing and you dont know how to do sumthin, and you need to ask an internet forum for help... You might want to get a pro.. I am not a pro but i do have a basic understanding and those pictures of how he wired it first and what it did to that plug, make me cringe... Electricity does not forgive, and can bite hard.. So if unsure please seek professional help...


later chris

 

[ureside]

this is not directed at the poster, just to all in general, when it comes to wireing and you dont know how to do sumthin, and you need to ask an internet forum for help... You might want to get a pro.. I am not a pro but i do have a basic understanding and those pictures of how he wired it first and what it did to that plug, make me cringe... Electricity does not forgive, and can bite hard.. So if unsure please seek professional help...


later chris

I thought ya'll were professionals!? i understand, and i have maybe a "growing" basic knowledge, but if it weren't for places like this... thers ALOT i wouldn't know how to do.