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Old 09-21-2011, 06:17 PM   #11
BigBobsBrews
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Quote:
Originally Posted by milldoggy View Post
Have you turned your breaker off and removed the dryer plug? I bet you have a forth wire in there.
Well, I'll be damned once I pulled the outlet I found there are 4 wires hiding in there. Thanks for that.

Now I just gotta rewire the dryer & convert it to a 4 prong outlet.

 
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Old 09-21-2011, 08:56 PM   #12
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There you go, might want to test the forth wire and make sure it is wired to the ground bar in the panel. Not sure how to do this, but someone on here can tell you how.
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Old 09-22-2011, 11:33 AM   #13
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Originally Posted by flananuts View Post
I actually had problems running my 120 v march pumps and my 240 elements on the same circuit. It created enough current imbalance(notsurenthe right term) that it would throw the breaker. I had an electrician confirm this for me.
Your 240 VAC GFCI breaker is comparing one leg to the other (it doesn't need the neutral). When you use a single pole device on a 2 pole GFCI, it'll trip because it sees it as a fault.

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Old 09-22-2011, 11:45 AM   #14
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On many older 240 VAC devices (dryers, A/Cs, ovens, etc.) the neutral was not hooked up because it wasn't needed. The currents on the two legs cancelled each other out. Appliances now have more electronics in them (lighting digital displays, etc.) that are 120 VAC, so they need an insulated conductor for the neutral. There's really no need to rewire your dryer (unless you want to).
A 3 wire 30A GFCI for all your 240 VAC stuff and another 120 VAC GFCI circuit for the rest.

 
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Old 09-22-2011, 10:01 PM   #15
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Quote:
Originally Posted by milldoggy View Post
There you go, might want to test the forth wire and make sure it is wired to the ground bar in the panel. Not sure how to do this, but someone on here can tell you how.
Open up the panel and check the cable coming in. It should be 10/3 (black, red, white and ground). Follow the white wire to the neutral/ground "bus." If it's not connected, find an empty slot on the bar and screw it in. If all the neutrals are on one side and all the grounds are on the other, follow suit. If it's been cut short, wire nut a short length of #10 AWG so it can reach the bus. Pete

 
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Old 09-22-2011, 10:23 PM   #16
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Thanks for all the info, it's really appreciated

 
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Old 09-23-2011, 12:34 AM   #17
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Quote:
Originally Posted by petey_c
Open up the panel and check the cable coming in. It should be 10/3 (black, red, white and ground). Follow the white wire to the neutral/ground "bus." If it's not connected, find an empty slot on the bar and screw it in. If all the neutrals are on one side and all the grounds are on the other, follow suit. If it's been cut short, wire nut a short length of #10 AWG so it can reach the bus. Pete
Can't you test with meter also?
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Old 09-23-2011, 01:25 AM   #18
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Quote:
Originally Posted by BigBobsBrews View Post
Well, I'll be damned once I pulled the outlet I found there are 4 wires hiding in there. Thanks for that.

Now I just gotta rewire the dryer & convert it to a 4 prong outlet.
You said there were 4 wires in the outlet box. Which 3 of the 4 were connected to the outlet?

The dryer is probably wired with the 240V plus the neutral. Most are. When you complete the change to a 4 wire system and install a 4 wire cord on your dryer, you must remove the green jumper clip between the neutral connection and the dryer cabinet. The green wire from your new dryer power cord will then go to the dryer cabinet where that jumper clip was.

HTH

 
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Old 09-23-2011, 01:49 AM   #19
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Gents,

There are 3-wire and 4-wire GFCI devices available; spa panels are of the four wire variety so you can run both 240V and 120V circuits through the same GFCI. Pulling a 120V circuit from a 3-wire GFCI will cause it to trip. From what I understand, the 4-wire variety sums the current draw of both hot legs and compares it to the neutral leg; the GFCI will trip if any current leaks to the ground.
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Old 09-23-2011, 09:19 AM   #20
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Quote:
Originally Posted by milldoggy View Post
Can't you test with meter also?
Yes. Check for continuity between the neutral and ground wires. If it's not a sub panel (and it's wired correctly) you should get zero ohms or an indication of continuity on your meter. The neutral and ground are electrically at the same point.

pvtschultz Good to know. Thanks, Pete

 
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