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Hello folks.

I was at a video game convention recently and came across these portable "mega power strips", for lack of a better term. It looks like a subpanel with a bunch of outlet boxes attached, connected to a three-phase 120/208 outlet.

I'm just wondering if these things are legal. I've seen many photos of "home-made power strips" that use outlet boxes derided in the violation forum, and got curious when I saw these being used to provide power at the convention center.

The photo is attached; hopefully it comes through okay.

Attached picture thesethings.jpg
Looks pretty dodgy; most production/expo companies would use spider-boxes or other purpose-built, UL-listed distro equipment. Boxes like that are subjected to a lot of physical abuse.
Since these things are by default used in temporary power aplications, does the NEC even apply?
"Seems pretty dodgy."

Sure, and I've seen the rants against the extension cords with boxes mounted on the ends of them, with (at the minimum) the assertion that pendant rules apply.

Another maven of the seminar crowd recently crowed that 'changes' to OSHA rules pertty much ban the use of anything home-built where there is a listed product manufacturered. (Alas, he used the entire CFR as his citation, so I have yet to find the 'change' he was referencing.)

Balderdash! Since when did we make individual effort illegal? Maybe stick-built homes will be banned next, as there are many fine 'manufactured and UL-listed" homes available!

Just because something is site-made does not mean it's automatically wrong.

I applaud the guy's effort at making his own 'spider box.' Please note that most 'factory' boxes have far fewer receptacles, and use twist-lock types instead. This guy has the bases covered: support, over-current protection, strain relief, etc.

While I might have done it differently, those are differences in design only.

Let's face it: despite the tremendous range of products available commercially, there are still situations where the factory-,ade products are lacking. Perhaps the most obvious is the lack of space; plug in one 'wall wart,' and you've taken several receptacles out of service. That just might be why there are so many receptacles on this board.

If - and it's a big if - one were to find fault with this product, it would be the lack of GFCI protection. That is an issue that can be readily addressed just by replacing a few receptacles.
At the college where i used to work we made several of these,a bit more professional looking.

We used 100A main breaker 3 ph. mounted to 2 wheel dollies. used them at all the various functions around campus,all GFI.
We had various spots with 100 pin/sleeve rec to power them.

This made function set up a snap.
The NEC does cover temporary installations. From what I can see in the picture, there is only one fairly minor violation, disconnecting means are not labeled as to what receptacles they serve.
I have one of these in my garage. I use for a disaster restoration company I work for. I use all the time as temp power after fires. Most fires do not damage the service so we are able to plug into the range with it and give them the power they need. Many time 5 or 6 dryers and fans. I have set it up so it can be madified to be used as a temp service. Have not had an inspector fail it yet.
I think I would pull out 590 and 525 to see which applied to the subject installation ... if I was actually in a position to inspect it at all. Usually these things are just the source of some interesting pictures for a "building" inspector. The life safety officers or fire marshals may be able to step in but the building department is not involved unless there is a permit pulled.

Maybe 525.22? 23?
Not one GFCI. That is the problem I am having. Is it just sitting on the floor??? What is wrong with these folks?
I'm wondering how they ran the wire between the boxes and the panel... I'm betting they are just going thru open KOs. At least they cater to both the ground up and ground down (and sideways) people :-)
/mike
Gfretwell: 525, dealing with carnivals and similar functions, is a fair section to reference. I think your citations of 525.22 and 525.23 are quite proper, and more appropriate than just the catch-all category of 'temporary installations,' Asticle 590.

That said, it appears to me that this assembly can certainly qualify. Mounted on the same board as it is, I think we have to interpret 'within the box' requirement of 535.24 to have been met; we certainly apply that standard to main disconnect / gutter / meter-main assemblies.

n1ist, I wouldn't doubt that everything is connected with chase nipples. I might even accept simple plastic bushings, as long as some means is used to ensure grounding continuity.

When I come across such a construction - or, when I make one myself - I ask whether I think the thing would meet the requirements a commercial product would have to meet. I'm willing to cut the maker some slack; for example, the DIY 'extansion cord light fixture' featured elsewhere on this forum lacks a sticker specifying the largest wattage lamp, and I would not hold that against a guy in the field.

The next question is whether the item is appropriate for the circumstances. Again, as an example, commercially made 'spider boxes' are made for use in wet locations, while this assembly is not. Is it in a wet location? If not, I see no need for it to meet those requirements.

The final factor ought to apply equally to all items, whether DIY or factory made: Maintenance.

In the debate of DIY cords, many photos were posted of damaged assemblies, often missing parts. That's not fair; anything can be broken. If the equipment is damaged or incomplete, it needs to be taken out of service, regardless of whether or not it has a "UL sticker."
Originally Posted by waymag
Not one GFCI. That is the problem I am having. Is it just sitting on the floor??? What is wrong with these folks?


Yep, they were laying on the floor, leaned up against columns, lying flat under tables, and so on.

There were various types; some were just full of NEMA 5-20 outlets like the one there; I saw others with NEMA L5-30, NEMA L6-20 or 30 and other outlet types in a few of the boxes.

It's inventive; if they need a specific type of outlet somewhere on the floor, they just have to pull the right one out of storage and bring it out.
Necessity, The 'mother' of invention.

My Mom, never made a mistake!

GFI at a minimum. Failed temp status.

Just me.
I looked at it and 2 things bother me. The SO cord in the Romex connector and there is something wrong if this is really 3p, How do you get "220v"? (breakers 1 & 2) and is this really a 3p panel?

That does look like a Russell Stoll 7328/7428 (60a 208 3p) plug/receptacle in the background but I don't see any numbers.
Originally Posted by waymag
Not one GFCI. That is the problem I am having. Is it just sitting on the floor??? What is wrong with these folks?


I can think of no requirement for GFI protection based on the NEC. This is not a construction site, so Article 590 does not require GFI protection. Judging by the enclosures, this is an indoor installation, so the requirements in 210.8(B) (4) do not apply either.
Greg, the two-screw romex connector is almost certainly also listed for SO, though I also would prefer a connector with better strain relief.

There are two different strain relief test standards, but the code does nt address the issue. UL standards do address this point, and I'm pretty sure they would also require a better grip; but as far as the NEC is concerned, it gats a 'pass.'

I do not think it's three-phase; I'm pretty sure that panel is available in single phase only. (After all, there's only one row of breakers).

Tom, I think we can find the GFCI requirement when we apply Article 525 (Carnivals and Fairs) to this gizmo, though the GFCI can be part of the plugs on the cords, rather than built into this assembly.
I guess I just remember getting beat up about those kind of connectors when we could still use SO cord under computer room floors. They wanted some kind of cord grip with a rubber insert and a locking ring like the RS devices use.

Of course when they said everything had to be FMC they just used the regular clamp connectors that immediately pulled out and you were looking at unprotected THHN.
Those were designed for a raceway that gets strapped within 12" of the box according to a rep I talked to about it.
Yea, those little 'assumptions' the factory makes, that they don't tell you about!

The issue of support is probably what's at the core of the different strain relief tests. IIRC, the two-screw connectors would only be tested to a 35# pull, while the ones with the rubber grommets get a 90# pull. (Anyone who knows better, please correct me!)
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