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Electrical codes in building DIY distro?

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Tim McCulloch:

--- Quote from: Sam Saponaro Jr on October 02, 2019, 01:10:50 am ---Ooohh.........and there you have it.
Wow I remember allot of bands with homemade distros not terribly long ago made from service entrance panels and long cables with both breakers and (Eeekk) clamps.Hell we had a panel mounted in a rack with a gazzilion foot feeder cable and breakers to terminate at the panel with one group I was with. Either they were illegal then or codes have changed....either way there goes that idea. :( :(

--- End quote ---

I remember Tweco clamps, undersized feeders and open knock outs in breaker panels screwed to plywood.  Those won't pass muster these days.

Recently changed Code now requires "Listed" (as in by UL or other appropriate authority) *assemblies*, not just Listed components.  Getting a distro Listed is expensive - because it's about more than just 1 unit, it's about the shop, materials, methods and procedures.  For example, LEX, TMB ProPower, Indu, Whirlwind, Motion Labs... all have UL-Listed shops and they spend a whole bunch of $$ getting those Listings (far more than for just 1 product) so they can build a variety of designs, not just 1 or 2 products.

JR designed a nifty little outlet tester that could detect RPBG (reversed polarity, bootleg ground) Edison outlet wiring.  It was a simple device with about 6 components.  It was going to cost over $10k to get it UL Listed.

While I don't recall hearing about any recent electrical fires or personal injuries from "lesser" distros, the NFPA 70 committee has been tightening the standards for portable switchboards over the last couple of Code cycles.  They seem to think there are still some shady and potentially dangerous portable AC systems out there.

If your locale has not adopted the most recent Codes you *might* get away with a home-brew distro for awhile.  Your chances of being inspected are proportional to the level of events you do:  working bars and clubs means you'll probably never see an inspector but doing county fairs, municipal events, anything with temporary demountable entertainment structures (stages and roofs) significantly increase the likelihood of inspector visits.

John Roberts {JR}:

--- Quote from: Tim McCulloch on October 02, 2019, 10:00:16 am ---I remember Tweco clamps, undersized feeders and open knock outs in breaker panels screwed to plywood.  Those won't pass muster these days.

Recently changed Code now requires "Listed" (as in by UL or other appropriate authority) *assemblies*, not just Listed components.  Getting a distro Listed is expensive - because it's about more than just 1 unit, it's about the shop, materials, methods and procedures.  For example, LEX, TMB ProPower, Indu, Whirlwind, Motion Labs... all have UL-Listed shops and they spend a whole bunch of $$ getting those Listings (far more than for just 1 product) so they can build a variety of designs, not just 1 or 2 products.

JR designed a nifty little outlet tester that could detect RPBG (reversed polarity, bootleg ground) Edison outlet wiring.  It was a simple device with about 6 components.  It was going to cost over $10k to get it UL Listed.

--- End quote ---
More than 6 components but indeed UL is a profit making business. I had to pay them hundreds of dollars just to buy a copy of the applicable UL spec (that I can't share). Then thousands of dollars to wrestle with them, all for a SKU that should retail for less than my BOM cost to compete with crap 3 lamp testers.

Not only does UL need to vet the design, but they even inspect/certify the factory where it is built to insure that the design is accurately assembled to plan, using approved components.

JR 

--- Quote ---While I don't recall hearing about any recent electrical fires or personal injuries from "lesser" distros, the NFPA 70 committee has been tightening the standards for portable switchboards over the last couple of Code cycles.  They seem to think there are still some shady and potentially dangerous portable AC systems out there.

If your locale has not adopted the most recent Codes you *might* get away with a home-brew distro for awhile.  Your chances of being inspected are proportional to the level of events you do:  working bars and clubs means you'll probably never see an inspector but doing county fairs, municipal events, anything with temporary demountable entertainment structures (stages and roofs) significantly increase the likelihood of inspector visits.

--- End quote ---

Jamin Lynch:
What about one of these?

Jeff Bankston:

--- Quote from: Jamin Lynch on October 02, 2019, 12:15:32 pm ---What about one of these?

--- End quote ---
I use those spider boxes to plug the guitar amps and keyboards into.

Rob Spence:
I wonder if the NEC was really after the crappy hotel ballroom home brew distros? Every one I have seen made me squirm.

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