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50amp outlets

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Jamin Lynch:

--- Quote from: Jonathan Johnson on October 06, 2013, 09:57:14 PM ---Are there people capable of performing electrical work safely and according to code without being a licensed electrician? Absolutely.

Are there licensed electricians who take shortcuts that jeopardize life and property, backed by inspectors that just sign off because they see that electrician's name on the permit? Yup.

Does your ability to perform work safely without license or permit absolve you from liability and protect you from legal action if someone does get hurt on that installation -- even if it's not your fault? Nope, not a chance.

It's simple to put a clause in the contract that says, "Contractor reserves the right to have electrical service inspected by an independent electrician or inspector of his choosing prior to connection to ensure adequacy and safety. Any deficiencies shall be rectified at the venue's/promoter's expense before connection. Failure to rectify deficiencies in a timely fashion will result in cancellation of this contract prior to the event and forfeiture of any deposit paid."

Now that I've summed up this thread, perhaps the admins can lock it. This horse is dead.

--- End quote ---

I thought this was dead a long time ago, but people gotta just keep repeating the same old thing over again. You didn't say anything different than a bunch have already said before. So you need to let it die. Mike pretty much answered my question a long time ago, everybody else is just bitching.

Adam Whetham:

--- 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 ---

Consider yourself lucky then. They are still scattered everywhere up in the midwest where I'm at. I carry a 14-50 distro, and have had a few places switch their power connection, many still stick with the 10-50R as "everyone else" doesn't have a problem with it. But most of these places also have a ground post next to the receptacle to connect to. It's metered out fine, and I've never had an issue before.

The one I don't carry that I run into every once in a while is a 6-50R. You don't know back woods until this is what they have for you to play in/behind the community center and they unplug the Miller rig for you. (I've had the local town electrician tie in for those, as I carry a 14-50R to tails with me when I'm going somewhere I haven't gone before.

Jonathan Johnson:

--- Quote from: Adam Whetham on October 21, 2013, 11:17:02 AM ---Consider yourself lucky then. They are still scattered everywhere up in the midwest where I'm at. I carry a 14-50 distro, and have had a few places switch their power connection, many still stick with the 10-50R as "everyone else" doesn't have a problem with it. But most of these places also have a ground post next to the receptacle to connect to. It's metered out fine, and I've never had an issue before.

The one I don't carry that I run into every once in a while is a 6-50R. You don't know back woods until this is what they have for you to play in/behind the community center and they unplug the Miller rig for you. (I've had the local town electrician tie in for those, as I carry a 14-50R to tails with me when I'm going somewhere I haven't gone before.

--- End quote ---

I was really hoping this thread was dead because of all the back-and-forth bickering over safety and licensing, but since you brought up  NEMA 10-50R, 14-50R, and 6-50R, I though it might be helpful to clarify the difference between these form factors.

* NEMA 6-50R: Nominally 250V 50A. The grounding conductor supplying this receptacle might be conduit or a derated, bare or green insulated conductor (such as an 8 AWG copper ground conductor with 6 AWG copper hot conductors). The grounding conductor is not intended to serve as a neutral, therefore it is not permissible to derive 125V power from this receptacle. Typically used with welders.
* NEMA 10-50R: Nominally 125/250V 50A. This receptacle has a shared grounding/neutral conductor. The neutral wire must be insulated and the same gauge as the hot conductors. In practice, this is often not the case; there are many poor installations that simply use an uninsulated grounding wire for the neutral connection. Note that the chassis of the appliance is bonded (connected) to the neutral wire at a terminal block where the cordset enters the appliance; there should be no other connection. Typically used with kitchen ranges prior to 1999, when their use was deprecated by the National Electrical Code.
* NEMA 14-50R: Nominally 125/250V 50A. This receptacle has separate ground and neutral conductors. The neutral conductor should be the same gauge as the hot conductors; the grounding conductor might be conduit or might be a derated, bare or green insulated conductor (for example, 6 AWG hot and neutral conductors; 8 AWG grounding conductor). Typically used with kitchen ranges, but may be used for any application requiring both 125V and 250V power up to 50A. Effectively replaces NEMA 10-50R.As you can see, the big difference between these has to do with how the grounding and neutral conductors are handled. Both NEMA 6-50R and 10-50R receptacles may have implications with audio systems; a NEMA 14-50R receptacle should provide safe, relatively noise-free power distribution providing it is installed correctly.

My preference for distribution would be a 125/250V locking connector, for which there doesn't appear to be a NEMA standard (even though you'll see reference to L14-50, it doesn't appear to be a NEMA designation). I see reference to a "California Standard" CS6364, but I don't know enough about that to speak authoritatively.

In my experience, there are many homes built in the 80's and 90's which have a NEMA 10-50R receptacle installed for the range, but the in-wall wiring includes both a neutral and a grounding conductor. Quite often this was done because the homeowner bought a range and was sold a NEMA 10-50P cordset, or they removed the old NEMA 10-50P cordset from their old range to put on the new one. (The irony is that is is cheaper and easier to replace the cordset with the proper one than replace the receptacle in the wall with the improper one.) In these cases, it's a simple matter to replace the receptacle with a code-compliant NEMA 14-50R receptacle, and replace the pigtail on the range with a NEMA 14-50P cordset, being sure to break the bond between the chassis and the neutral at the range's terminal block. (Same goes for clothes dryers, too -- except you'll use a NEMA 14-30R receptacle and 14-30P cordset.)

Mike Sokol:

--- Quote from: Jonathan Johnson on October 21, 2013, 04:21:56 PM ---I was really hoping this thread was dead because of all the back-and-forth bickering over safety and licensing.

--- End quote ---

I agree. Unless you have something new to add, then let's declare this thread finished.

John Fruits:
First off, my apologies for posting BUT there seems to be a strange thing going on with forums and 50amp connectors, check out this (now locked) thread at ControlBooth.com.
http://www.controlbooth.com/threads/50amp-hubbell-to-l6-30.33876/

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