120/240 volt receptacle?

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kwired

Electron manager
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NE Nebraska
Lots of stuff used to use the neutral as an EGC. For instance, old radios, old amplifiers, pretty much anything with a metal chassis that existed before a separate grounding conductor was part of the system.

I realize that, but most of what you mentioned was also 120 volt equipment, was there much out there that operated at 120/240 besides ranges and dryers was kind of what I was after? Every instance I have seen that 20 amp 125/250 receptacle it was used for an application that did not require a neutral and the neutral terminal of the receptacle was effectively only performing the function of equipment grounding, even if it truly was connected as a neutral.
 

K8MHZ

Senior Member
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Michigan. It's a beautiful peninsula, I've looked
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I realize that, but most of what you mentioned was also 120 volt equipment, was there much out there that operated at 120/240 besides ranges and dryers was kind of what I was after? Every instance I have seen that 20 amp 125/250 receptacle it was used for an application that did not require a neutral and the neutral terminal of the receptacle was effectively only performing the function of equipment grounding, even if it truly was connected as a neutral.

The only other thing I can think of is, possibly, air conditioners. 240 volt with 120 volt controls....that's just a guess.

Or maybe a deep freeze unit. 240 volt with a 120 volt light.

Those are just possibilities, like you, all I have ever seen is ranges / dryers set up like that (in residences).
 

iwire

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41QpAiSUMwL._SL500_AA300_.jpg

For the sake of discussion does anyone see an issue with supplying this outlet with a single circuit?
 
I am putting this in Continuing Education because, well, because I learned something and thought I would share it here.

I had a person show me a load controller with receptacles on the side in a catalog of electrical stuff. The pic wasn't clear, but it looked like your basic 120 volt non decora type receptacle.

The description said, 'dual voltage receptacles accept either 120 or 240 volt plugs'.

Hmm.....

I have never heard of such a thing. But they are out there. Here is a pic.

41QpAiSUMwL._SL500_AA300_.jpg

That's a Leviton sold on Amazon.

I have been at this a long time and have never seen such a receptacle. Have I been asleep at the wheel or is this just such a rare item it's not uncommon for them to never be seen in the wild?

The top is a NEMA 6 20R, 20A/250V receptacle and the bottom is NEMA 5 20R, 20A/120V receptacle. Both voltage and current is keyed to prevent the wrong plug to be inserted.

A 15A plug of the appropriate voltage could still be plugged into the coresponding voltage receptacle. That they are within the same duplex is economics driven.
 
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texie

Senior Member
Location
Fort Collins, Colorado
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Electrician, Contractor, Inspector
For the sake of discussion does anyone see an issue with supplying this outlet with a single circuit?

I think the trick here is that you would need to supply it from a common trip breaker-handle ties would not qualify. See 210.4(C) Exception #2.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
It's upside down.




/ducks and runs...

Like my avatar?

FWIW, I grabbed an older GFCI out of my collection to put in my garage. If you didn't put the ground toward the top, the 'test' and 'reset' markings were upside down.

I put the ground on the bottom. I have my reasons, aside from convention, to do it that way MOST of the time.

Have you tried to use a Kill-a-Watt on a low receptacle mounted 'ground up'? Can't read it!!! I have, in my TE box, a short extension cord for the purpose of being able to read the meter. Some ice cube testers have the writing only on one side, too. Short ext. cord works good for that, as well.

Now that there ARE reasons for a certain type of mounting, we may need an adaptor. A ground up to ground down adaptor for test equipment.

Million dollar idea, right there!
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
For the sake of discussion does anyone see an issue with supplying this outlet with a single circuit?

Design wise, yes. I would prefer to have the receptacles on seperate circuits so tripping the OCPD for one would not affect the other......but......

I would have to look, but I don't the the NEC would allow that, since there is a common yoke involved.
 

roger

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Fl
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Retired Electrician
Design wise, yes. I would prefer to have the receptacles on seperate circuits so tripping the OCPD for one would not affect the other......but......

I would have to look, but I don't the the NEC would allow that, since there is a common yoke involved.
See 210.7(B)

Roger
 

roger

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So handle ties, but no common trip would be OK? And do they make a handle tie that would connect a 2 pole breaker to a single pole breaker?

I see the allowance, I am just not sure about how it would be done with the funky receptacle.
I am pretty sure there are handle ties are listed for this purpose. There would be no reason to trip the other circuit(s) if only one had a fault or overload, the requirement is that all the circuits feeding one yoke must be able to be disconnected simultaneously.

Roger
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
I am pretty sure there are handle ties are listed for this purpose. There would be no reason to trip the other circuit(s) if only one had a fault or overload, the requirement is that all the circuits feeding one yoke must be able to be disconnected simultaneously.

Roger

Put them close to each other??

That's only partially joking. Technically, if I can turn off both breakers at the same time, have I not fulfilled the requirement? All that is required is a 'means to simultaneously disconnect'.

Nothing says there shall be a means to prevent independent disconnection, which I think is what they mean.

Too bad we don't have a code consultant here somewhere......:)
 

roger

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Fl
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Retired Electrician
Put them close to each other??

That's only partially joking. Technically, if I can turn off both breakers at the same time, have I not fulfilled the requirement?
Absolutely
All that is required is a 'means to simultaneously disconnect'.
Correct

Nothing says there shall be a means to prevent independent disconnection, which I think is what they mean.
That is also correct and an easy way to do this is set switches ahead of the circuits even immediately outside of the load center or panelboard


Roger
 

fmtjfw

Senior Member
So handle ties, but no common trip would be OK? And do they make a handle tie that would connect a 2 pole breaker to a single pole breaker?

I see the allowance, I am just not sure about how it would be done with the funky receptacle.

You place the 1 pole beside the 2 pole, pry the 2-pole handle tie off and replace it with a 3-pole handle tie.
 

kwired

Electron manager
Location
NE Nebraska
For the sake of discussion does anyone see an issue with supplying this outlet with a single circuit?

Without a doubt.

So let me rephrase, does anyone have an issue in supplying these two outlets with a single MWBC.

I do not, but it seems some do.

I think you about have to, unless you come up with a way to disconnect all ungrounded conductors. 3p 4w MWBC, Handle tie between single and double pole breaker - if there is one intended to be used for this, or this:

You place the 1 pole beside the 2 pole, pry the 2-pole handle tie off and replace it with a 3-pole handle tie.

Not sure if you are joking or not, but will say that if I need to buy a 3 pole breaker in order to remove the handle tie, I would just install the three pole breaker in the first place - of course that will mean common trip, but if the double pole trips it may have enough pulling force to shut off the single pole anyway effectively still making it kind of sort of common trip.
 

fmtjfw

Senior Member
I think you about have to, unless you come up with a way to disconnect all ungrounded conductors. 3p 4w MWBC, Handle tie between single and double pole breaker - if there is one intended to be used for this, or this:



Not sure if you are joking or not, but will say that if I need to buy a 3 pole breaker in order to remove the handle tie, I would just install the three pole breaker in the first place - of course that will mean common trip, but if the double pole trips it may have enough pulling force to shut off the single pole anyway effectively still making it kind of sort of common trip.

You can buy handle ties by the bag.
 
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