Pigtail conversion

Hey Hivemind.

So we are looking at purchasing some used ETC Smartbar 2s, specifically the SB4-10-Bs.

They come with the 20a pigtails.

In our wall we have L21 20R twistlock.

I'm like 95% certain that this wont be an issue since both are 20a and I can just swap out the pigtail with a male L21 20R but I'm horrified I'm going to screw up my first purchase for this PAC

Is there anything I'm failing to consider??

Okay, I'll bite.

If I understand your situation, what you propose is acceptable. You're "wasting" two legs of perfectly good power but that doesn't seem to be an issue. HOWEVER, some of your nomenclature confuses things quite a bit.

rsiminoski said:

specifically the SB4-10-Bs.

They come with the 20a pigtails.

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Pigtails are found on the output of dimmers/circuits on raceways/connector strips. The SB4-10-B does not have pigtails at all, but rather 2P&G flush-mount stage pins for dimmer outputs. Input is 5-20P. An input to a dimmer enclosure is usually called tails, but that's not exactly accurate in this case as there's only one and tails is usually single-pole connectors.

rsiminoski said:

a male L21 20R

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There's no such thing. Akin to asking for a male girl. The R stands for Receptacle (female, flush-mount). You want an L21-20P (for plug, male). You may also see L21-20C (connector, female cord-mount), which might come into play should you need to extend the distance between the supply receptacle and the SmartBar box.

Something to consider, depending on how many of these things you're deploying: Should you use the same hot leg every time on the L21-20P, or do you mix it up?

Thanks for this. Can you tell I'm not an electrician?

Yes I'm talking about the input on the unit itself which is 5-20p.

Thank you for the clarification on the difference between receptacle, plug, and connector.

With that clarified I am hoping to replace the 5-20p input with a L21-20P so I don't need to use adaptors which will just get hot and seem unnecessary.

Sounds like this won't cause any issues?

rsiminoski said:

Thanks for this. Can you tell I'm not an electrician?

Yes I'm talking about the input on the unit itself which is 5-20p.

Thank you for the clarification on the difference between receptacle, plug, and connector.

With that clarified I am hoping to replace the 5-20p input with a L21-20P so I don't need to use adaptors which will just get hot and seem unnecessary.

Sounds like this won't cause any issues?

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Or if you want to fully utilize all three phases you could simply go this way:
https://lexproducts.com/powerflex_detail?part=4125-L21-L520

I would get an adapter and make use of the legs completely. Here are some things you can get. You could go the breaker stringer route which is nice.

Or

You could just go straight in and out



Obviously these are the 30a versions but the the statement runs the same. Each one of those legs could run a smart bar each.

The breakout box is a good suggestion. Or, have an electrician give you a permanent solution by changing the three phase twistlock receptacle to three, single phase receptacles. You can't have too many circuits around.

Amiers said:

You could just go straight in and out

View attachment 23081

Obviously these are the 30a versions but the the statement runs the same. Each one of those legs could run a smart bar each.

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I can't see how the "cubetap style" does not violate NEC 520.69(A), Adapters:

(A) No Reduction in Current Rating
Each receptacle and its corresponding cable shall have the same current and voltage rating as the plug supplying it. It shall not be utilized in a stage circuit with a greater current rating.

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Thirty is still more than twenty, right? Points for them being "T-slot, combo, 15/20" though.
OP has stated he doesn't want adapters if he can avoid them, and in this case he can. Y'all is over-thinking this.

derekleffew said:

I can't see how the "cubetap style" does not violate NEC 520.69(A), Adapters:

Thirty is still more than twenty, right? Points for them being "T-slot, combo, 15/20" though.
OP has stated he doesn't want adapters if he can avoid them, and in this case he can. Y'all is over-thinking this.

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I believe the suggestion was a 21-20-> 3x 5-20 adaptor, which wouldn't create any issues, although it appears that the box indicated includes independent OCP for each phase, which means it's probably code complaint as long as the cable connections are 10gauge.

The time for an electrician to come out and do the work is going to easily offset any differences between having them swap a 21-30r to a single 5-20r ( and fix breaker) and 3x5-20R (and fix breaker

Yes, we can tell you're not an electrician.

You might want to contemplate what your fire insuror will do if you have an electrical fire later traced to these changes not made by a licensed electrician. :-}

Beware of internet advice, there's always more to the story.

Your L21-20s most likely have a single neutral, so trying to get 3 circuits out of them might overload the neutral. There are many threads here on the dimmer neutrals. Your plan of putting L21-20P on the dimmers fairly safe and simple. Wiring them to various hot legs will distribute the load across the phases.

If you need more circuits get the electrician out, or buy the 3 phase SmartBars.

The SmartBars have a label on them indicating the proper type of power to supply to them. ETC also provides some of the best documentation I've seen from a manufacturer, and equipment spec sheets are available through their website. (Even for legacy products, which I believe the SmartBars now fall under.)

Generally, changing the plugs on equipment voids the UL rating. Doesn't seem to matter, except when it does. So, in your case, the SmartBar requires one 20A input (at 120V, that's a 2400W load), and distributes it over four, 600W circuits. Changing it to a L21-20 plug, however, would imply to an outside party that it's actually taking in three, 20A circuits. There's a different version of the SmartBar that actually does require this, because it provides six, 10A circuits. So, again, an outside party might think the individual circuits are capable of supporting a higher load, or that the entire SmartBar is capable of supporting a higher load, both of which are false.

Amiers' adapter is probably the right way to go, short-term (but -- uhhhh, look at that strain relief). If everything is correctly loaded, nothing should get warmer than it would in operation without it. It would be one additional point of potential failure (disconnecting, or physically catching on something else), so the more ideal solution would be to get the proper circuit for the equipment installed, rather than try to fool the equipment into believing it's something it's not.