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#121619 - 08/02/05 08:52 AM Why Panels Have So Many Knock-outs (not)
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 Quote:
This industrial establishment needed a receptacle for some of their equipment.

The breaker in the panel serves the pigtail- which exits the panel through the large opening, and just sort of "hangs" there. Should the door be closed, the next guy gets to "fish" it off the bussbars.

- renosteinke

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#121620 - 08/02/05 06:41 PM Re: Why Panels Have So Many Knock-outs (not)
sierra electrician Offline
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Registered: 02/12/05
Posts: 220
Loc: North Fork, CA USA
This is a good find. Is there a "Best Violation" contest? Here is a candidate!

Rob

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#121621 - 08/02/05 06:43 PM Re: Why Panels Have So Many Knock-outs (not)
sierra electrician Offline
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Registered: 02/12/05
Posts: 220
Loc: North Fork, CA USA
It looks as though the cord is Main Lugged with no protection.

Rob

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#121622 - 08/02/05 06:52 PM Re: Why Panels Have So Many Knock-outs (not)
renosteinke Offline
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Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
Yes, Rob, it does LOOK that way...but it does terminate at one of the two breakers that you see. (The other serves the receptacle next to the panel)
What is also misleading is that, while this plug may look like a 240v "dryer" cord, it is not; it is a non-NEMA 125v/30a pattern used by the RV industry.

So, the breakers are a single 1-pole, 20 amp and a single 1-pole 30 amp.

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#121623 - 08/04/05 12:40 AM Re: Why Panels Have So Many Knock-outs (not)
Trumpy Offline

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Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Just a little side-note guys.
I don't know, over the time that I've been here at ECNet, how many times I've seen plugs hanging half-way out of recepts!.
Surely it must be a violation of some sort to have the plug, bear the weight of a heavy cord?.
I'm not sure how long the pins are on these plugs, but wouldn't it cause burning of the mating contacts when current is drawn through the cord?.
This sort of thing sort of winds me up a tad.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

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#121624 - 08/04/05 05:20 PM Re: Why Panels Have So Many Knock-outs (not)
renosteinke Offline
Cat Servant
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Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
Trumpy,

You are right to worry about half-out plugs. As far as I can remember, these were the sorts of things always used as examples of how home fires start.

If a plug is just barely making contact with the receptacle, and there is a sizeable load on it, the plug prongs can get red-hot. As you might guess, this sort of heat will cause the wire insulation in the cord, the receptacle, and the wires in the box to degrade, and eventually fail.

Just the sort of thing the AFCI was originally claimed to protect us from.....but that's another story.

One of the big differences between a quality device, and a residential one, is the amount of tension in the springs that hold the plug in. All devices will weaken eventually- but if a receptacle is used frequently, or is expected to hold against the weight of a substantial cord, getting a better device to start with makes sense.

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#121625 - 08/04/05 06:43 PM Re: Why Panels Have So Many Knock-outs (not)
NORCAL Offline
Member

Registered: 09/25/02
Posts: 807
On a minor note, see a BR circuit breaker in a I-T-E panel.

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