Tools & Fabrication - 220V Wiring ?s.
09-07-2008, 03:48 PM
I'm trying to wire a 220v 30a to my garage, I bought a 30a 2 post for the circuit box. I'm getting 120 volts per side, but only 6.5 amps per side. Did I buy the wrong circuit breaker?
09-07-2008, 07:05 PM
I have a 2 wire 10 gauge wire with one ground. The white wire and black wire going to each side of the breaker, and ground wire going the neutral bar. Unable to turn on my welder. What gives?
09-07-2008, 07:58 PM
How are you measuring the 6.5 amps?
Sounds like it should be right. Do you have 220V between the poles of the breaker?
09-07-2008, 08:00 PM
how long is the run? where are you testing the voltage at? breaker or plug?
09-08-2008, 05:01 AM
I'm checking it with a multimeter. At the plug.
09-08-2008, 06:27 AM
You can't check amps like that. You measure the draw.
09-08-2008, 07:47 AM
Yeah, you stick a multimeter between the leads of a plug with it set on amps, that's a good way to pop your multimeter. I'd be surprised if you didn't pop an internal fuse in it.
To measure amps with a multimeter, you either need to have a amp hoop that goes around the wire (inductive pickup), or you cut in to the load wire, put one side of the cut wire on one lead, other side on the other lead. A multimeter that can measure 30A at 220V this way would have to be a pretty nice (stout) unit. Most won't.
Really, all you can check with a multimeter most of the time is voltage. If you have 220V between the 2 hot posts, then you're good there. It becomes a matter of how big your welder is, and what kind of inrush current it has. If you're sticking a 250A-300A welder on a 30A circuit, you may or may not be able to power it up because of current inrush - that might trip the breaker. A 30A circuit should be good for most 250A or less welders and motors up to 5-6 horsepower though. You probably wouldn't be able to run a 250A welder at full tilt, but lower settings should be OK...
Is the welder just not powering up, or is it tripping the breaker?
09-08-2008, 08:10 AM
I don't have 220V between the two Leads.
09-08-2008, 09:51 PM
You didn't buy one of those mini double breakers, where they both fit into a standard (one inch) space, did you?
09-09-2008, 10:06 PM
Sounds like thats whats going on. Take your meter and go between the two legs on the breaker itself. You should have 220. If you dont you have a faulty breaker or like what was said above, one that both sides of the breaker are on the same bus.
09-10-2008, 05:00 AM
That's my problem, the wrong breaker.
09-11-2008, 12:47 AM
please dont tell me you got 2 15a...
09-12-2008, 08:44 AM
No, I bought a two pole 30amp breaker, that was only 1" thick. I needed one that is 2" think.
09-12-2008, 01:42 PM
you need a two pole 30 not a twin 30 which is what ya needed.....Bassicly you were only pulling from phaze A...two pole will get ya Phaze A and Phaze B. If you dont have the room in your panel for another breaker you can just twin up any two standard 110 lines with a twin 15. You should see 240volts when you have the leads in from the two hot legs and 120 from each hot leg to ground.
This is a twin which you have: http://www.electricsupplyonline.com/prod/circuit_breakers-murray/mp1515n_w002406.php
This is what ya need: http://www.electricsupplyonline.com/prod/circuit_breakers-murray/mp230_w002416.php
09-12-2008, 03:39 PM
09-13-2008, 09:01 PM
lol I had to rewire my friends shop because of the same thing. Just make sure you read your panelboard and make sure the breaker will hit both legs and you'll be good to go
09-15-2008, 02:13 PM
Got it running, just need some compressor oil. Oh, and my freaking Power Back On!
I'll be posting pics of my DIY Air Compressor, as soon as I figure out how to post pics.