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50amp outlets

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Steve M Smith:
You Americans certainly have a strange assortment of power outlets!


Rob Spence:

--- Quote from: RYAN LOUDMUSIC JENKINS on September 19, 2013, 10:49:54 AM ---Are you sure it as no ground or is it no neutral?  In almost 25 years running audio, I have never come across a 50 amp without a ground.  The 50 amp 125/250 volt receptacle does exist in the Nema 10-50R but I have never come across one.  Are you working in some really old venues?   We do have an old hotel here that had a couple 10-30R recepticals that they supossedly were upgrading and may already be done with but no 50s.

--- End quote ---

I did a gig a few years back that had a 10-50R next to a sub panel. I made them replace it with a 14-50R before I would use it (discovered weeks before the gig).

My electric range came with a 10-50P on it. I had the cord set replaced before I could use it.

They are pretty common up here in the northeast. Of course, all newer construction has the 4 wire versions.

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Mike Sokol:

--- Quote from: Steve M Smith on September 19, 2013, 01:19:36 PM ---You Americans certainly have a strange assortment of power outlets!

--- End quote ---

Yes we do. I've worked for a British sound company here in the US for 20 years, and always laughed at our US power outlets.

Jonathan Johnson:

--- Quote from: Jamin Lynch on September 19, 2013, 11:03:46 AM ---Yep. 2 hots and a neutral.

--- End quote ---

This is a typical older style range receptacle conforming to the NEMA 10-50 spec. You'll notice that right on the front, it says "50A 125/250V" and "NEMA 10-50R."  In the typical application with a slide-in kitchen range, the neutral (the lower, vertical slot in this picture) is actually a shared neutral/ground, and the chassis of the range is bonded at the range's terminal block to the neutral+ground wire in the cordset. (Note that the NEMA 10-30 used to be used for clothes dryers similarly to ranges; this has been replaced with the NEMA 14-30.)

Current electrical code does not permit this style of plug to be used anymore; for new construction, your kitchen range must use a NEMA 14-50 receptacle and plug which provides separate neutral and ground contacts.

Here's a useful chart (courtesy Wikimedia) which applies to North America:

Jonathan Johnson:
For high-amperage receptacles (30A or higher) the ground pin is typically installed at the top of the receptacle as most cordsets with right-angle plugs will have the ground pin opposite the cord entrance.

That's a fancy way of saying "so the cord be hangin' down."

For 20A and 15A receptacles, the debates for whether the ground pin should be up ("safety!") or down ("my wife says it needs to look like a face!") are endless. To my knowledge, the National Electrical Code gives no requirements for receptacle orientation.


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