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Author Topic: Feeder Cable length?  (Read 8914 times)

Tim McCulloch

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Re: Feeder Cable length?
« Reply #10 on: May 28, 2014, 10:05:00 am »

Is that acceptable by code? I have never seen it done on high voltage before... Speaker lines sure..


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It's allowed for single conductor feeders, same length, etc.  Not sure about doing so with multi-conductor cables...
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Kevin Graf

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Re: Feeder Cable length?
« Reply #11 on: May 28, 2014, 01:25:40 pm »

In most cases the NEC only permits 1/0AWG and larger wires to be paralleled.
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Jeff Bankston

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Re: Feeder Cable length?
« Reply #12 on: May 28, 2014, 05:05:41 pm »

Is that acceptable by code? I have never seen it done on high voltage before... Speaker lines sure..


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i'v never seen where it not. its no different from running multiple leg runs of 4/0 from a generator to a distribution panel like at concerts and movie sets.
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Stephen Swaffer

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Re: Feeder Cable length?
« Reply #13 on: May 28, 2014, 11:48:19 pm »

NEC 310.10(H)(1) Limits paralleled conductors to 1/0 AWG and larger.  There are some exceptions but generally anything smaller is required to be protected at the ampacity of each individual conductor-mainly intended to allow redundant control conductors for reliability not extra current capacity.

Guess I wouldn't be comfortable with 2 male plugs paralleled together myself-can't seem to get away from Murphy's law in my neck of the woods!

Also, with tripping the 30 amp breaker.  You may well have been running over 30 amps, but I have seen many cases where a loose wire on the breaker will create enough heat (most breakers are both thermal and magnetic sensitive) to cause it to trip at a much lower current-same can happen with fuses.
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David Sturzenbecher

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Re: Feeder Cable length?
« Reply #14 on: May 28, 2014, 11:53:58 pm »


NEC 310.10(H)(1) Limits paralleled conductors to 1/0 AWG and larger.  There are some exceptions but generally anything smaller is required to be protected at the ampacity of each individual conductor-mainly intended to allow redundant control conductors for reliability not extra current capacity.

Guess I wouldn't be comfortable with 2 male plugs paralleled together myself-can't seem to get away from Murphy's law in my neck of the woods!



This is why this is a bad and code breaking idea!! If your combiner is connected at the far end, plugging one male end into the outlet energizes the exposed prongs on the second male end.


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Jeff Bankston

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Re: Feeder Cable length?
« Reply #15 on: May 29, 2014, 01:48:45 am »

yeah but you are refering to extension cords and not a permanent installation. that why nec cannot regulate what people do with an extesion cord in side or outside. in cali only osha can regulate temp power cords on a job site. i can use the same spider box in my house and osha cannot come in and write me a fine up. what i suggested is not for just anyone and if i absolutely need a larger cord i would buy the larger cord.
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Stephen Swaffer

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Re: Feeder Cable length?
« Reply #16 on: May 29, 2014, 07:28:05 am »

The OP was asking about an extension feeder in a public venue where he has both a legal and ethical responsibility to provide a safe environment.  IMO in these situations OSHA, NIOSH and the NEC are a starting point. 

My former employer often required going above and beyond to insure safety.  When the public (I viewed production employees as 'public') is involved the mindset can't be "Can this be done safely by a reasonable person?" as much as, "Is there any way an careless person can get hurt here?"  People can be seriously creative when it comes to finding ways to get hurt-no sense in making it easy for them.
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Michael Ardai, N1IST

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Re: Feeder Cable length?
« Reply #17 on: May 31, 2014, 08:47:06 pm »

NEC 406.7 prohibits male plugs with energized prongs.  So it is a code violation as well as a potentially lethal safety issue.
/mike
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James Cotton

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Re: Feeder Cable length?
« Reply #18 on: June 04, 2014, 04:35:01 pm »

you could run 2 paralell extension cords into a 2 in 1 out box.

In the UK that kinda thing is commonly known as a "widow maker". I'd have thought in the US you'd never even contemplate such a cable for fear of lawyers, never mind that it might kill someone who comes along looking for an outlet to plug the coffee pot into and cares little for what that plug may be powering.
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TJ (Tom) Cornish

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Re: Feeder Cable length?
« Reply #19 on: June 04, 2014, 04:50:02 pm »

In the UK that kinda thing is commonly known as a "widow maker". I'd have thought in the US you'd never even contemplate such a cable for fear of lawyers, never mind that it might kill someone who comes along looking for an outlet to plug the coffee pot into and cares little for what that plug may be powering.
It's equally unsafe/illegal/idiotic here. 
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ProSoundWeb Community

Re: Feeder Cable length?
« Reply #19 on: June 04, 2014, 04:50:02 pm »


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