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gus6464

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I have a 240V 30A dryer outlet in my garage that I am not using as our dryer is gas. I wanted to covert the plug to a 20A 240V. The plug is the older type NEMA 10-30 240/120 combo which has no ground but 2 hots and neutral. Is converting as simple as pulling the 30A breaker and getting a double pole 20A, connect the two hots but then take neutral and move it to ground? Want to replace with a NEMA 6-20.
 

Awesome Dennis

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I have a 240V 30A dryer outlet in my garage that I am not using as our dryer is gas. I wanted to covert the plug to a 20A 240V. The plug is the older type NEMA 10-30 240/120 combo which has no ground but 2 hots and neutral. Is converting as simple as pulling the 30A breaker and getting a double pole 20A, connect the two hots but then take neutral and move it to ground? Want to replace with a NEMA 6-20.

*** just reread your post and Misunderstood what you were trying to do.
And yes you could do what your asking. That would give you 20A 240v.
 
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gus6464

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You would make it a single pole 20A breaker and 1 spare. Black would be your 120v line power, white would stay neutral and the red would be tapped green on the whole wire in box and in panel and installed in ground bar. If the outlet is located behind tank and unserviceable you can install a GFI breaker and a regular outlet.

So what do I do to make it 240v? Isn't 240V on a nema 6-20 just 2 hots on the breaker and a ground?
 

Awesome Dennis

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I edited my original post. My only question to ask is the panel your changing the breaker in does it have the main breaker inside it?
 

RamsReef

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I have a 240V 30A dryer outlet in my garage that I am not using as our dryer is gas. I wanted to covert the plug to a 20A 240V. The plug is the older type NEMA 10-30 240/120 combo which has no ground but 2 hots and neutral. Is converting as simple as pulling the 30A breaker and getting a double pole 20A, connect the two hots but then take neutral and move it to ground? Want to replace with a NEMA 6-20.
You would replace the breaker.
If your wire has a ground you would use that and tape the neutral.
If your wire does not have a ground you would move the neutral to the ground bar in your panel, and wrap some green tape on it.
At the other end where your receptacle is you would do the same, tap the neutral green (Just one wrap is fine), and wire as you indicated.

This is out of my area of expertise though.
 

Paul B

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Unless you are in Tibet, Istambul, Ocho Rio's or the Moon, you are using 220. It's actually closer to 208 or so but it is called 220 in the US. :D
Or maybe I assumed wrong :eek:
 
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RamsReef

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Youve been 3 phasing to long Paul.

Single phase windings should be 240 center tapped to give two 120 legs.

Not the vector of two 120 volt legs from a wye.
 

Brew12

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Youve been 3 phasing to long Paul.

Single phase windings should be 240 center tapped to give two 120 legs.

Not the vector of two 120 volt legs from a wye.
Hmm.. well.. if we didn't know before it is clear that PaulB has an industrial background!
 

Paul B

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Youve been 3 phasing to long Paul.

Single phase windings should be 240 center tapped to give two 120 legs.

Not the vector of two 120 volt legs from a wye.

Get a voltmeter and measure it. :eek:

Hmm.. well.. if we didn't know before it is clear that PaulB has an industrial background!

Very industrial. Everything now commercial is 277/480. It is really quite lower than that but what do I know? I am old and probably senile. :confused:
 

Brew12

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Get a voltmeter and measure it. :eek:

I have measured both at work and at home. At work, since I maintain my 34.5kV system a bit high, I typically see around 213V.

At home, I typically run 113V-115V on my outlets and 226V-230V on my 240V outlets.



Very industrial. Everything now commercial is 277/480. It is really quite lower than that but what do I know? I am old and probably senile. :confused:
You've probably forgotten more about many things most of us never learned. For instance, I would be shocked if you haven't used Scott T transformers or Zig Zag transformers.

The latest trend in industrial is actually to make 277V go away in favor of restively grounded 480V systems. With the improvements in industrial LED lighting, the 208V systems are really making a comeback.
 

Paul B

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I started as a construction electrician in 1972 in Manhattan. One of my first jobs was on the construction of the World Trade center. I also renovated the Plaza Hotel. Helped build the New York Playboy Club (where I would have worked for free) as well as being the general foreman on Penthouse Magazine (where I would have paid them to work) and we built many sky scrapers in New York City. All of them are 277/480 but we all know they are a lot less due to resistance.
Our houses are said to be 120 or even 115 but they are probably less depending on how far we are from the transformer.
But I have been retired for 9 years so now maybe we don't use those voltages any longer. As far as I know we now use chicken soup for electricity. :eek:
Somewhere on this thread it was said the OP was using an air conditioning outlet. I doubt that is a 140 volt outlet, but as I said, I am old and retired and senile, so it could be. :p

In the lower picture I am CAD welding in a New York City garbage incinerator. Not a place you want to go for your honeymoon as the maggots were up to your ankles. The top picture I am hanging off the roof of the Plaza hotel. I used those fixtures in my tank for years. That is snow covered Central Park below me,

 

RamsReef

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Paul B must stand for Paul Bologna :p

20161014_154254.jpg
 

Paul B

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Oh No, your house in Tibet is broken :eek:

I wondered why they wanted me to retire. :cool:
 
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Paul B

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I am going to go and stick my head in mud now. I am senile. NNNNNNNNNNNNNNNNoooooooooooooooooo :eek:
 

RamsReef

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The old Edison 3 wire finally did you in eh?

Like my avatar?
 

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