ETC SmartBar/Smart Module

Jezza

Active Member
Hey All-

-Specking equipment for a theater renovation right now -- wondering what all your thoughts are on either the Smart Bar or Smart Modules.

-I'd like to dedicate the two main dimming racks to FOH and the on stage Electrics power (electrics have connector strips on them). However, I'd like to use Smart Bars to mount on booms for side light and Smart Modules for other stage level dimming like ground row cyc cells, practicals, etc. We do several dead hung trussing shows each year and being able to truss mount the bars or the modules seems like a great idea instead of lots of single runs pulling off the electrics.

-Just wondering whether anyone has any experience with these.

Thanks
 
While I don't have experience with the ETC brand of those particular devices, I do have experience with lesser, competing products. Some advice:

If possible, standardize on the L21-30 connector instead of the L21-20. Not that much more expensive, and better to oversize. Likewise, all of your 100' or longer cables should be 10/5 instead of 12/5. The supplying circuit breaker must be a 20A 3pole type. This and the supply wiring materials and labor cost can add up quickly, but often can be "hidden" in the building's electrical contractor budget rather than the stage lighting budget.

Invest in many opto-isolators, and bundle (using friction tape), a DMX cable with every power cable. Have a 120Ω DMX Terminator on the end of every power/data bundle, so it's there when you need it. Ideally, you want to install as many L21-30R and D5Fs in as many locations as you can, minimally on both sides of the stage and upstage L&R for your cyc lighting.

I think it's a great idea to "hybridize" a system like this, with both portable dimmers and installed racks. Maximum flexibility, and labor-saving in the long run.

Consider building some, L21-20P to (3x) L6-20R, 208V "breakouts" so you can easily power/data moving lights, as well. Stagger the females every 10' and maybe harness the DMX jumpers to that also. This could be "phase two," but something to make provisions for now.

Hope this helps.

Edit: Hey STEVETERRY, referencing this document, "The 6x10A SmartModule is supplied with a flange mounted GTL receptacle." I'm surmising an L21-20P, possibly the Hubbell #HBL2515, or equivalent. Document also says "supply shall be a 12/5 cable." If the pack is loaded to capacity, wouldn't the neutral wire (and connector) be overloaded by a factor of 1.732, any time the dimmers are less than Full? Should one consider using 12/6 or 10/6 cable and doubling the neutral (provided one could fit two wires into the connector's terminal)?
 
Last edited:
Thanks for the tip about the 30A cable -- I'll change that on the documentation.

As it is, I've got 8 power and data drops (2US, 2DS, 2SL in Grid for Booms 2 SR in Grid for Booms). We've got a pretty low trim height and static grid so I'm going to beam clamp some junction boxes to the steel so I can just slap a Smart Bar to a boom and run the power and data UP instead of down -- no cables for the kiddies to trip over.

Good hint about the ML distro solution. I'll have to take that into consideration. Do you know if anyone makes such a thing as a stock item?

I too like the hyrbid of modular and installed dimming. Allows me to keep a relatively standard rep plot up, but also do a lot of changes/additions easily. The Smart Modules seem like a good solution for our space -- some Smart Bars are going out to the FOH torms already.

Thanks Derek!
 
...Good hint about the ML distro solution. I'll have to take that into consideration. Do you know if anyone makes such a thing as a stock item?...
Not as a stock item that I know of, but look into NuTech or Lex Products. Both can build anything of which you can dream, at a significant cost, and will insist on adding branch circuit breakers, which is never a bad thing.
 
Edit: Hey STEVETERRY, referencing this document, "The 6x10A SmartModule is supplied with a flange mounted GTL receptacle." I'm surmising an L21-20P, possibly the Hubbell #HBL2515, or equivalent. Document also says "supply shall be a 12/5 cable." If the pack is loaded to capacity, wouldn't the neutral wire (and connector) be overloaded by a factor of 1.732, any time the dimmers are less than Full? Should one consider using 12/6 or 10/6 cable and doubling the neutral (provided one could fit two wires into the connector's terminal)?

The 12/5 cable will not be over loaded because:
A. The four current-carrying wires heat as a system and 3 of them are at less than full load when the neutral is at 1.3 (this is the typical overcurrent in phase control dimming systems, not 1.73) times the max phase current.

B.The ampacities in table 400.5 column B are for 60 degree C portable cords. Almost all Type SO and similar cords are now made in 90 degrees C. You can find the ratings for 90 degree C portable cord in table 520.44. 12AWG cable with three current-carrying conductors is rated at 35A. Since our neutral must be considered a current-carrying conductor per 520.27(B)(1) we have four current-carrying conductors and must derate the ampacity to 80% per 520.44. 35A x 80%= 28A. This requires 50% diversity, so there is a lot of headroom at 20A.

The one caveat in this application is the temperature rating of the connector, which must be 90 degrees for the above to work.
Having said all that, when we implemented a distributed dimming system in rental stock at Production Arts, we used 10/5 cable on L21-20 20A connectors to deal with voltage drop. There was never a problem with neutral overcurrent causing the connectors to fail. Perhaps that's because in practice most 10A dimmers are loaded to 575W or 750W, not their 1200W nameplate rating.

I don't like the idea of 6 conductor cables--the connector terminals are not designed to accept that much copper.

ST
 
So, IF (big "if") I understand correctly:
10/5 cable is good,
but L21-30 connectors are overkill?

The OP is going to be putting 1Kw cyclight loads on his SmartBar/SmartModule dimmers. If his supply voltage is as low as 110V, that's 18+ amps on #12AWG cable, for sustained periods, hence my concerns. Of course I'm not worried a bit about ETC's engineering, but rather what the Electrical Contractor, who may not understand theatrical lighting, does. I'm always reminded of the first job a Broadway Lighting Designer did as a Theatre Consultant, where the conduit containing the FOH circuits got so hot one couldn't hold one's hand on it.

Where did I get the constant "1.732" from?:rolleyes: Maybe I just dreamed up that number!
 
Hey All-
-Specking equipment for a theater renovation right now -- wondering what all your thoughts are on either the Smart Bar or Smart Modules.
-I'd like to dedicate the two main dimming racks to FOH and the on stage Electrics power (electrics have connector strips on them). However, I'd like to use Smart Bars to mount on booms for side light and Smart Modules for other stage level dimming like ground row cyc cells, practicals, etc. We do several dead hung trussing shows each year and being able to truss mount the bars or the modules seems like a great idea instead of lots of single runs pulling off the electrics.
-Just wondering whether anyone has any experience with these.
Thanks

Sorta tangential:

Is it specking, or spec'ing? I tend to go with the latter.
 
Sorta tangential:
Is it specking, or spec'ing? I tend to go with the latter.
The proper form of the word is specifying, so you are correct in your assumption.
Putting a k in the middle of the word would screw up the pronunciation.
 
I haven't been known as being a stellar speller. Sorry -- and yes it should be specifying.

Nice use of "tangential" though Charc :)

Thanks to Steve and Derek -- Got some things sorted out.
 
So, IF (big "if") I understand correctly:
10/5 cable is good,
but L21-30 connectors are overkill?
The OP is going to be putting 1Kw cyclight loads on his SmartBar/SmartModule dimmers. If his supply voltage is as low as 110V, that's 18+ amps on #12AWG cable, for sustained periods, hence my concerns. Of course I'm not worried a bit about ETC's engineering, but rather what the Electrical Contractor, who may not understand theatrical lighting, does. I'm always reminded of the first job a Broadway Lighting Designer did as a Theatre Consultant, where the conduit containing the FOH circuits got so hot one couldn't hold one's hand on it.
Where did I get the constant "1.732" from?:rolleyes: Maybe I just dreamed up that number!

(with apologies in advance)

A lower voltage of 110V means a lower current: 15.26A for 2 x 1000W lamps rated at 120V. Yours is a common misconception. The lamp wattage is for its rated voltage. Lower voltage=lower wattage and lower current


110/120=.916

1000W/120v=8.33A

8.33*.916=7.63A

7.63x2=15.26A @110V


ST
 
I haven't been known as being a stellar speller. Sorry -- and yes it should be specifying.
Nice use of "tangential" though Charc :)
Thanks to Steve and Derek -- Got some things sorted out.

I hope that you were being serious, and not mocking me, as I have SATs tomorrow. While I hardly consider "tangential" and SAT word, one can never be too prepared!
 
Just testing to see if you were paying attention, STEVETERRY!;)

Charc: complete the following: "ETC:Lighting as Strand:x". Now get off here and study so you can get into a good school and make us proud. Otherwise you may end up at Ithaca!:twisted:
 
Just testing to see if you were paying attention, STEVETERRY!;)
Charc: complete the following: "ETC:Lighting as Strand:x". Now get off here and study so you can get into a good school and make us proud. Otherwise you may end up at Ithaca!:twisted:

ETC: Lighting as Strand: Lighting.

They both sell consoles. They both sell dimmers. They both sell ERSs. Only one sells Fresnels (don't even think of bringing up the PARnel).

Strand/Genlyte/Phillips for the win! :twisted:
 

Users who are viewing this thread

Back