Thread: Mixed circuits and voltage in common gang box

Looking for the code on this one.

Here is the hypothetical situation.

Lets say you have a double gang box and in that you have one receptacle that is a 120v duplex and the other receptacle is a single 240 receptacle, different circuits.

Anything that says that this can not be done?

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None that I am aware of and I can't see where it would be any more problematic than a multiwire circuit.

Gents,

That is what I thought. I had someone say that it was not proper and I thought that was not correct. I was looking through the codes and could not find anything that would prevent that. but thought I would through it out to the masses to see if anyone had anything.

Originally Posted by Don Hester

Gents,

That is what I thought. I had someone say that it was not proper and I thought that was not correct. I was looking through the codes and could not find anything that would prevent that. but thought I would through it out to the masses to see if anyone had anything.

That person may have been thinking about NEC article 406.5(G) for receptacles or 404.8(B) for switches.

406.5(G)
A receptacle shall not be grouped or ganged in enclosures with other receptacles, snap switches,or similar devices,unless they are arranged so that the voltage between adjacent devices does not exceed 300 volts or unless, they are installed in enclosures equipped eith identified,securely installed barriers between adjacent devices.

404.8(B) says the same things
You should never have to deal with this in a dwellings as the voltage in dwellings is normally 120/240.

I think that's a very good question. This wouldn't be a situation against the electrical code in Canada, but realistically you might have a hard time to find a double gang wall plate with the right cut-outs to fit a duplex 120V receptacle and a 240V receptacle side by side.

Originally Posted by Mann Chiang

I think that's a very good question. This wouldn't be a situation against the electrical code in Canada, but realistically you might have a hard time to find a double gang wall plate with the right cut-outs to fit a duplex 120V receptacle and a 240V receptacle side by side.

They (face plates) are readily available in both traditional and decora styles (125V receptacles or combo devices), or single switch in conjunction with a round opening for a 250V NEMA receptacle opening.

Back to general discussion:

Lets say you have a double gang box and in that you have one receptacle that is a 120v duplex and the other receptacle is a single 240 receptacle, different circuits.

Anything that says that this can not be done?

Depending on the depth, fill capacity of the box (plaster ring, plate/cover, wiring method...)


May require a 3-gang box with a reducing ring on the face to accomodate fill capacity and spacing, esp. with modern wiring requirements for circuits. (esp. with arc fault and gfci sensativities - need a 4-wire circuit for the 250v receptacle and if split duplex or split combo device if metal box/faceplate) may need extra capacity for fill on box. May require additional space and/or derating if installing a rheo, dimmer, or similar switch, and may require additional space for combo gfci or afci device for fill ratios.


Communications "outlets" and wiring thereto should be separated. May run into difficulty if wireless router, some semi-wireless networks (using branch circuitry for communication signals, x-10, and the like are on the 125V circuits, if not mainting spacing, division, and non-conductive box/plate. If supplied by separate system (i.e. gen outlet, LV secondary lighting control, etc.) should be separated by divider.

If its 2-wire circuits as RM suggests should be non-conductive box and faceplate, esp. if gfci or afci on ckt(s).

(Note: modern receptacles are "rated" or designsted as 125V and 250V, respectively; "Edison" or generic household supply is generally categorized or designated as 120/240V).

HTH

If have a multi-branch circuit, example each half of a duplex feed by a separate circuit, should have a common breaker with a tie bar, but I see nothing related to two separate devices/plugs in same box restriction ?

Good stuff guys. I think we were all on the same page. I am usually pretty good at finding the exception but sometimes they are buried or I was just not see the sharp object in my eye .

Thanks for all the responses.