Local custom or standard practice?

"All multi-pole, multi-circuit connectors shall be clearly marked with the voltage of the branch circuits serviced by the connector."
Does this mean that the same piece of multicable will need different labeling if used with a 208/240v distro vs a 120v distro?
That is absolutely correct. Trunk cable multiconnectors feeding 120V breakouts must be marked 120V, while trunk cable connectors feeding 208V breakouts must be marked 208V. Marking need not be permanent, just "clear".

ST
 
Little off topic, I did a tour of Oklahoma, thought I'd have a little fun with mult labels, so I used cow-cow, pig-pig, Horse - well, you get the idea....

It was terrible, most folks didnt get it, I had to go back and relabel them all A, B, C...., I guess I am not as fun as I thought...

Oh, they didnt get "Das Feeder" box either....

Just trying to have a little bit of fun.....
Sean...
 
Little off topic, I did a tour of Oklahoma, thought I'd have a little fun with mult labels, so I used cow-cow, pig-pig, Horse - well, you get the idea....

It was terrible, most folks didnt get it, I had to go back and relabel them all A, B, C...., I guess I am not as fun as I thought...

Oh, they didnt get "Das Feeder" box either....

Just trying to have a little bit of fun.....
Sean...
Well I AM from Oklahoma, I know about electricity, and I certainly don't get it either. You really must be not as fun as you thought.:confused:
 
Little off topic, I did a tour of Oklahoma, thought I'd have a little fun with mult labels, so I used cow-cow, pig-pig, Horse - well, you get the idea....

It was terrible, most folks didnt get it, I had to go back and relabel them all A, B, C...., I guess I am not as fun as I thought...

Oh, they didnt get "Das Feeder" box either....

Just trying to have a little bit of fun.....
Sean...
You needed to use words from the songs "Chicks and ducks and geese better scurry when I take you out in the surry...."

Although "issinglass" might be confusing...
 
But then, I would say that, since I wrote it-- in 1993, and happily it was adopted into the 1996 NEC.
Oh sure, bring that up! <surrenders> 🩲 (closest I could find to waving a white flag).

I'm not disparaging any of the work you've done, and continue to do, I'm just saying I think you could/should have at least mentioned break-in the underdog. "When Polly's in trouble, I am not slow..." I honestly can't tell you that last time I used a break-in. But it's still nice to know it's there.
-----
And finally, in 2023 addressing the issue of the bi-voltage Socapex 419 connector.

This story is worth repeating...
After watching six (expensive 2K Fresnel) lamps blow, in sequence,
"I told you to label the cable."
"No, I told you to label the cable."
I guess the cable never got labelled.
 
Well I AM from Oklahoma, I know about electricity, and I certainly don't get it either. You really must be not as fun as you thought.:confused:
I too am from Oklahoma and since the noize boiz had SNAKES I had eelectrics for the multi circuit cables.
 
"All multi-pole, multi-circuit connectors shall be clearly marked with the voltage of the branch circuits serviced by the connector."
Does this mean that the same piece of multicable will need different labeling if used with a 208/240v distro vs a 120v distro?
My guess is the straight lengths of multi are not needing labels since no device connects to them directly, but on the break-out/ins we'll need to label with what the voltage is, but isn't that odd since we should be using NEMA connectors which are voltage specific??
 
My guess is the straight lengths of multi are not needing labels...
Yes and no. The cable itself does not need a label, but it does say "ALL...[Soco]...connectors". So every multi-cable gets two labels, one at each end.

... but isn't that odd since we should be using NEMA connectors which are voltage specific??
The fixture/device end(s) (females) of the break-out has single-pole connectors that are already labeled as to voltage (albeit often in tiny typeface) from the manufacturer.

... but isn't that odd since we should be using NEMA connectors which are voltage specific??
Not that odd. Due to the huge installed base, some usage and practices just get grandfathered in, as it were.
 
but isn't that odd since we should be using NEMA connectors which are voltage specific??
And what prevents you from plugging in the wrong breakout? Or, from plugging the other end of the Soco into the wrong connector on the power distro? Obviously, stupid mistakes can still happen, but labeling reduces the chances a little.

The common usage of multi-cables in theatre for both 120 and 208 has always been gray at best, because the NEC doesn't generally allow the same connector to be used for different voltages in the same setting. This change is essentially adding a permission that was never there before by saying, "Okay, we recognize you're already doing this potentially very confusing and problematic thing, but at least label the crap out of everything so we can try to make it a little safer. Please?"
 
And what prevents you from plugging in the wrong breakout? Or, from plugging the other end of the Soco into the wrong connector on the power distro? Obviously, stupid mistakes can still happen, but labeling reduces the chances a little.

The common usage of multi-cables in theatre for both 120 and 208 has always been gray at best, because the NEC doesn't generally allow the same connector to be used for different voltages in the same setting. This change is essentially adding a permission that was never there before by saying, "Okay, we recognize you're already doing this potentially very confusing and problematic thing, but at least label the crap out of everything so we can try to make it a little safer. Please?"
Not quite.

Just like other things in the theatre (like single-conductor feeders) that require qualified persons, that is the case with Special-Purpose Multi-Circuit Cable Systems.

This is the full list of proposed requirements:

520.68(D) Special-Purpose Multi-Circuit Cable Systems.

Special-purpose multi-circuit cable systems shall comply with the following requirements:

(1) Branch circuits shall be rated at not more than 20 amperes and not more than 150 volts to ground.
(2) Trunk cable types shall be extra-hard usage (hard service) or hard usage (junior hard service).
(3) The ampacity of trunk cables shall be determined in accordance with Table 520.44(C)(2).
(4) Trunk cables, breakout assemblies, and multi-circuit enclosures shall be listed.
(5) Section 406.8 shall not apply to multi-circuit, multipole plugs or receptacles that are part of a special-purpose multi-circuit cable system.
(6) All multi-circuit, multipole connectors shall be clearly marked with the voltage of the branch circuits serviced by the connector.
(7) Installation and operation shall be performed by a qualified person(s).

And this is 406.8, which would no longer apply to these systems based on (5) above:

406.8 Noninterchangeability.
Receptacles, cord connectors, and attachment plugs shall be constructed such that receptacle or cord connectors do not accept an attachment plug with a different voltage or current rating from that for which the device is intended. However, a 20-ampere T-slot receptacle or cord connector shall be permitted to accept a 15-ampere attachment plug of the same voltage rating. Non–grounding-type receptacles and connectors shall not accept grounding-type attachment plugs.

Finally, do you have a better idea for a solution? If so, bring it on! The industry has steadfastly rejected multiple solutions to prevent intermating of 19-pin connectors operating at different voltages. That left us with the proposed NEC solution above, which at least makes these systems allowable by the NEC with the qualified person and listing provisos.


ST





 
Trunk cable types shall be

Finally, do you have a better idea for a solution? If so, bring it on! The industry has steadfastly rejected multiple solutions to prevent intermating of 19-pin connectors operating at different voltages. That left us with the proposed NEC solution above, which at least makes these systems allowable by the NEC with the qualified person and listing provisos.


ST





Just curious as to the term "trunk cable", as I associate that with only one stage lighting manufacturer which arguably is defunct.

I also notice the term "multi-cable" doesn't appear. Why?

Final question: Although targeted toward Socapex 419-compatibles, intentionally non-specific so as to encompass other connectors. Does anyone know if the Pyle-National 12/37 was ever used for anything other than 120V?

Final, final question/statement: I'm assuming this article will apply to the PRG S400 components, even though that system provides greater safety than merely labelling.
-----
I already use black or white tape for 120 and red tape for 208.
I already use letters for dimmer and numbers for 208 MLs.
So what this NEC change means to me:
I'll be also writing, as small as my Sharpie will allow, "120V" or "208V" on the label of every multi-connector. No biggie.
 
Just curious as to the term "trunk cable", as I associate that with only one stage lighting manufacturer which arguably is defunct.

I also notice the term "multi-cable" doesn't appear. Why?

Final question: Although targeted toward Socapex 419-compatibles, intentionally non-specific so as to encompass other connectors. Does anyone know if the Pyle-National 12/37 was ever used for anything other than 120V?

Final, final question/statement: I'm assuming this article will apply to the PRG S400 components, even though that system provides greater safety than merely labelling.
-----
I already use black or white tape for 120 and red tape for 208.
I already use letters for dimmer and numbers for 208 MLs.
So what this NEC change means to me:
I'll be also writing, as small as my Sharpie will allow, "120V" or "208V" on the label of every multi-connector. No biggie.
1. "Multi-circuit cable" was thought to be more explanatory to the NEC community than "multi-cable".
2. I know of no application in of Pyle 37-pin connectors in the entertainment industry at a branch circuit voltage greater than 120V.
3. I believe PRG S400 will fall under this new section.
4. I have always called it a "trunk cable" since 1982. A definition of trunk cable is also going into the 2023 NEC:

Trunk Cable.
A portable extension cable containing six or more branch circuits, a male multipole plug and a female multipole receptacle.

ST
 
Not quite.

Just like other things in the theatre (like single-conductor feeders) that require qualified persons, that is the case with Special-Purpose Multi-Circuit Cable Systems.

This is the full list of proposed requirements:

520.68(D) Special-Purpose Multi-Circuit Cable Systems.

Special-purpose multi-circuit cable systems shall comply with the following requirements:

(1) Branch circuits shall be rated at not more than 20 amperes and not more than 150 volts to ground.
(2) Trunk cable types shall be extra-hard usage (hard service) or hard usage (junior hard service).
(3) The ampacity of trunk cables shall be determined in accordance with Table 520.44(C)(2).
(4) Trunk cables, breakout assemblies, and multi-circuit enclosures shall be listed.
(5) Section 406.8 shall not apply to multi-circuit, multipole plugs or receptacles that are part of a special-purpose multi-circuit cable system.
(6) All multi-circuit, multipole connectors shall be clearly marked with the voltage of the branch circuits serviced by the connector.
(7) Installation and operation shall be performed by a qualified person(s).

And this is 406.8, which would no longer apply to these systems based on (5) above:

406.8 Noninterchangeability.
Receptacles, cord connectors, and attachment plugs shall be constructed such that receptacle or cord connectors do not accept an attachment plug with a different voltage or current rating from that for which the device is intended. However, a 20-ampere T-slot receptacle or cord connector shall be permitted to accept a 15-ampere attachment plug of the same voltage rating. Non–grounding-type receptacles and connectors shall not accept grounding-type attachment plugs.

Finally, do you have a better idea for a solution? If so, bring it on! The industry has steadfastly rejected multiple solutions to prevent intermating of 19-pin connectors operating at different voltages. That left us with the proposed NEC solution above, which at least makes these systems allowable by the NEC with the qualified person and listing provisos.


ST





In the process of CMP15 working on finalizing the 2023 NEC, I noticed a significant error in the proposed wording. This is especially annoying, since (mea culpa) I wrote the proposed wording. :)

Point 5 of the list should read as follows:

(5) Section 406.8 406.4(F) shall not apply to multi-circuit, multipole plugs or receptacles that are part of a special-purpose multi-circuit cable system.

And here is 406.4(F):

406.4(F) Noninterchangeable Types.
Receptacles connected to circuits that have different voltages, frequencies, or types of current (ac or dc) on the same premises shall be of such design that the attachment plugs used on these circuits are not interchangeable.

So, what's the (perhaps too subtle) difference between 406.8 and 406.4(F)?

406.4(F) prohibits the use of the same connector at different voltages, types of circuits (AC or DC) or frequencies in the same facility. The multicircuit, multipole connector of 520.68(D) must be exempt from this requirement, as it can be used at different voltages in the same facility or portable system. This is allowed because of the other caveats of 520.68(D) such as marking and use by qualified persons.

406.8 prohibits the mating of connectors with different ratings, with some noted exceptions. This prohibition still applies to 520.68(D).

The NEC correlating committee will be voting on correction of this error--we hope that they will approve the correction before publication of the 2023 edition.

ST
 
I have seen some systems where a multis feed 3x L6-30 instead of the 6x 20a circuits... (PRG S400, and some custom soco breakouts with matching distro)...
Is this something that should be verboten? is it covered somewhere else in code?

Just curious about the 20a limit.
 
Presumably they're doing three circuits because they are using conductors in parallel to theoretically cover the higher ampacity. The NEC doesn't recognize parallel conductors as a valid option until you get up into the big sizes... can't remember exactly where the line is offhand (and too lazy to look it up), but think 100s of amps rather than 10s.

If you keep it all 20A instead of 30A, then only using three circuits for 208V break in/outs is actually sort of a safer solution because you could wire it so you're just using the conductors that would normally be hot in the standard 6-circuit fashion. If you plug in the wrong breakout, your 120V loads just don't work (because the corresponding neutral isn't connected) rather than blowing up from getting a 208V surprise. Still lots of room for confusion with mixing the two, though.
 
I have seen some systems where a multis feed 3x L6-30 instead of the 6x 20a circuits... (PRG S400, and some custom soco breakouts with matching distro)...
Is this something that should be verboten? is it covered somewhere else in code?

Just curious about the 20a limit.
The proposal for this section was intended to recognize the de facto standard of 6 x 20A Socapex-type multicables. That is why the 20A limit exists. Paralleling of conductors smaller than 1/0 AWG is prohibited by section 310.10(G)(1). The only exceptions to this limitation are covered in 310.10(G)(1) Exceptions 1 and 2. Neither of these exceptions cover portable power distribution equipment where paralleled 20A conductors are used for a 30A lighting branch circuit. However, the distro you mention is Listed, but I can't offer an explanation of how that occurred in light of 310.10(G)(1). I spoke to Chris Conti of PRG prior to the submission of this proposal, but did not receive any rationale for inclusion in the proposal.

ST
 
And what prevents you from plugging in the wrong breakout? Or, from plugging the other end of the Soco into the wrong connector on the power distro? Obviously, stupid mistakes can still happen, but labeling reduces the chances a little.
I must throw a flag on both your assertion and Steve's reply:

If a soca is unlabeled, then the person about to plug in a fanout and fixtures *must check, right then* to make sure the fixtures match the source voltage.

But if there's a voltage marker flag on the load and -- and it is *wrong*, showing, say, 120 when the source is actually 208, cause some *other* person screwed up -- then you're still gonna blow lamps (at least).

I don't see any passive way to guarantee this problem won't bite you.

Soca plug with a small circuit board and 18 bicolor LEDs. Carry it in your pocket.
 
I must throw a flag on both your assertion and Steve's reply:

If a soca is unlabeled, then the person about to plug in a fanout and fixtures *must check, right then* to make sure the fixtures match the source voltage.

But if there's a voltage marker flag on the load and -- and it is *wrong*, showing, say, 120 when the source is actually 208, cause some *other* person screwed up -- then you're still gonna blow lamps (at least).

I don't see any passive way to guarantee this problem won't bite you.

Soca plug with a small circuit board and 18 bicolor LEDs. Carry it in your pocket.
A nice idea--but it assumes that the Socapex-type receptacle you are plugging is energized--which would generally not be the case.

See point 7 of the caveat list:
(7) Installation and operation shall be performed by a qualified person(s).



ST
 

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