50amp Hubbell to L6-30

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OKAY, Here is the thing all of you except the OP don't seem to understand. Lets say for the sake of simplicity, you want to put a home theater in you living room. Your living room has ONE 20a circuit, however there are 4 outlets in your living room wired to the same circuit(very common). All of the wiring in your house is 12ga, any single outlet is capable of a 20a load, or you could have 4 individual 5 amp loads on each outlet. It does not make any difference, because each outlet is wired with 12ga wire, rated for 20a. Now if you try to plug in all of you'r home theater and an air conditioner, it probably would exceed the 20A rating of the breaker, and trip, This is what the breaker supposed to do. BUT, if you decide not to turn on your TV, or surround sound, and to simply turn on a lamp, to read a book, you do not need to rush down to the basement and swap a 20a breaker for a 1 amp breaker, which do not exist anyway, because the 100w light bulb will only draw 100W. Even if you take the knife that you used to get the bread out of your toaster this morning, and stab the lamp cord, this will create a dead short, and the breaker will trip. That is how it works.
 
Previously I had typed out a longer reply, but I decided on a more effective, simpler rebuttal. If your logic holds true, why have OCPD on branch circuits at all? Why can't I just hook my extension cables for my 208v/10A lights right up to a distro feeding 800A/3Ø? I mean, after all, the transformer feeding that distro has OCPD. Additional OCPD between the 800A legs and my lighting instruments is just redundant.
 
Thanks for posting SOMETHING referencing a code, however a direct link would be more useful; a Google search turns up mostly idiots like us posting on forums, and GFCI outlets, which would be great if i were updating the electrical outlets in my bathroom.

I guess I don't rest my case, because there are fundamentals here that people don't understand.

Yes, that is correct--there are indeed fundamentals in this thread that show a misunderstanding of the National Electrical Code.

First, the branch circuit rating that a given piece of listed utilization equipment can be safely plugged into is determined by its listing requirements. Second, NEC section 520.69 specifically prohibits an adapter with a reduction in current rating. That is precisely the device you are suggesting in this thread. Another extreme example of such a device is the infamous 60A to 20A threefer.

Note that an adapter with a reduction in current rating is not the same issue as connecting a piece of listed utilization equipment to a branch circuit with a current rating larger than the power consumption of the device. This is covered by the device listing conditions.

As to a direct link to the applicable NEC sections, you can find the NEC at www.NFPA.org.

Also, in order to insure that facts are on your side, it is sometimes useful to actually read the applicable codes or standards before taking a strong position.

Finally, as a new member of Control Booth, you might want to consider a more measured approach, rather than coming in with all guns blazing. This is especially useful when your facts are incorrect.

Sincerely,

Steve Terry
VP R&D ETC
Member, National Electrical Code Panel 15
 
Ok, Focus, I'm going to try to keep this civil. First, since you seem more than willing to give out advice regarding electrical safety, please obtain a copy of the National Electrical Code. The current version is 2011. If you were to read through this you would understand why what you are proposing is simply wrong, as others have stated in this thread.

Ok, now let me respond to the issue at hand. The reason the 30A breaker is required is to protect against a fault between the overcurrent protection within the device and the L6-30 connector. This cable and the L6-30 connector will be sized by the projector manufacturer and covered under the UL listing for the device. The problem comes when you make an adapter that has a 30A connector protected by a 50A breaker. The 30A connector is not adequately protected. Your example comparing this to an alarm clock plugged into a 15A outlet, protected by a 20A breaker does not apply. 15A outlets on a 20A branch circuit are specifically allowed under 210.21(B)(3) as long as there is more than one outlet on the branch circuit. If the branch circuit has a single outlet, 210.21(B)(1) requires this outlet to be rated the same as the branch circuit rating. This would mean that a single outlet on a 50A branch circuit (branch circuit size is determined by the upstream overcurrent protection device) is required to be rated at 50A. Adding a 30A breaker inline makes a new 30A branch circuit that is allowed to have the L6-30 connector.

(I guess I didn't make it to the second page of posts before my resistance to reply failed. My apologies for any redundency.)
 
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Ok, Focus, I'm going to try to keep this civil. First, since you seem more than willing to give out advice regarding electrical safety, please obtain a copy of the National Electrical Code. The current version is 2011. If you were to read through this you would understand why what you are proposing is simply wrong, as others have stated in this thread.

This document happens to be accessible online at NFPA's website for online viewing for free.
 
Ya, but its not. It is against code, period. If you want it done correctly, you need to have a breaker that steps down the load, period. That connector is rated for 30 amps, therefore the circuit must be able to be de-energized if more then 30 amps is being pulled through the circuit. Building an adapter for this without the proper breaker/fuse in place is wreckless. You never know what the next guy is going to do or how long you will have your job. It does not cost that more to do this right. Your connecting a 10,000 dollar plus projector, the correct interconnect will cost you a hundred or two.... no reason to play games here.

Pedantic mode on
Footer I think you either mean it is reckless or wreckfull - not wreckless. Indeed if it were wreckless there would be (IMHO) no possibility of damage.

I think your 16 hour days are getting to you. Get some rest
 
Alright I'm done with this. The original question has been answered. Some of CB's top experts have clearly answered the question and been insulted. My personal thanks to those of you who held your tongue and remained civil. Thread closed.

@coolsvens send me a private message if you need further help on the topic or have a followup question and I'll get you the information you need.
 
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