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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Lighting Forum => Topic started by: Michael Miller on August 25, 2012, 03:17:55 AM

Title: Ideas for powering LEDs on a bar
Post by: Michael Miller on August 25, 2012, 03:17:55 AM
I have a small "self defense" lighting system for my hobby sound company which consists of 4 trees;

The front tree's each have 4 traditional S4 pars on a bar; I drop the bar on the top of the tree, mount a dimmer pack on the vertical pole near the top using an O-clamp, plug the lights in to the dimmer, run power & DMX to the dimmer, raise it up and zip tie the lines to the tower.  This works well, goes quick and looks neat & tidy.

The back tree's each have 4 Elation Opti Tri Par LEDs.  Getting power & DMX to each of these cans is a hassle and always looks messy.  So I'm looking for ways to streamline this process by pre-wiring the bar.

I'd like to, for example, figure out a way to pre-wire the power on the bar so I only have to run one power line to the bar.  I thought about simply zip-tieing a strip to the bar but that's kinda tacky.  A 4 outlet strip that mounts with an O-Clamp like my dimmer packs do would be nice too, but I know of no source for something like that.  (The bar is for ST-132 stands and has a short vertical section in the middle I could mount to as long as it doesn't interfere with the cans.)

Anyone have any clever ideas out there to make life easier with these cans?

Thanks,
Mike
Title: Re: Ideas for powering LEDs on a bar
Post by: Thomas Bishop on August 25, 2012, 01:05:25 PM
I'll try to get some pictures of how I wired mine. I used a power strip and it doesn't look tacky. It also allows me to jump the two bars together when on truss, as well as a place to plug in some other small non dim items (wireless dmx). I also have dmx prewired.
Title: Re: Ideas for powering LEDs on a bar
Post by: Jay Barracato on August 25, 2012, 01:34:34 PM
I have the adj with the iec pass thru. I use a 25 ft edison to iec to feed the tree and 3 foot iec to iec cables to imp to the other lights. They are zip tied in place with the dmx cables with enough slack to adjust or remove the lights.

If you don't have the pass through option I would use a quad drop from Windsor before I used a power strip.
Title: Re: Ideas for powering LEDs on a bar
Post by: Michael Miller on September 03, 2012, 06:45:06 PM
Well, here's what I came up with.  Not sure it's worth the effort and 6 trips to Home Depot, but it's functional.
Title: Ideas for powering LEDs on a bar
Post by: Rob Spence on September 03, 2012, 10:36:06 PM
It may work but it won't pass any NEC tests.


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Title: Re: Ideas for powering LEDs on a bar
Post by: Michael Miller on September 04, 2012, 11:43:39 AM
It may work but it won't pass any NEC tests.

I imagine there is a very good reason for each and every one of the NEC rules.  I have no significant investment (other than time) in this system and would not hesitate to pull it off and revert to an outlet strip if safety were a concern.  (And assuming an outlet strip is a safe alternative.)

What you can't see in the picture is that the splices are made with a screw fastener, soldered and then covered with heat shrink.  The metal box is tied to safety ground.  Each cable has strain relief to eliminate tension on the internal connections and the outer cable insulation extends 1/2" into the box.

If there are specific safety concerns, I really would like to hear about them so I can either address them or abandon this idea entirely.

Thanks,
Mike

Title: Ideas for powering LEDs on a bar
Post by: Rob Spence on September 04, 2012, 12:39:33 PM
The idea IS clever. However, the strain relief on the horizontal wires is designed for romex ( or more correctly, type NM ) and not for type SJ as you are using it. The code prohibits soldering connections where there is a proper screw fastener.

I suspect you don't work where wires get inspected so no one is likely to object. It is even likely better than many others do on a regular basis.

But, when you post home brew wiring on the Internet, you may get some comments on proper practice. I did on some of mine and I learned from it.


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Title: Re: Re: Ideas for powering LEDs on a bar
Post by: Jay Barracato on September 04, 2012, 02:01:02 PM
I imagine there is a very good reason for each and every one of the NEC rules.  I have no significant investment (other than time) in this system and would not hesitate to pull it off and revert to an outlet strip if safety were a concern.  (And assuming an outlet strip is a safe alternative.)

What you can't see in the picture is that the splices are made with a screw fastener, soldered and then covered with heat shrink.  The metal box is tied to safety ground.  Each cable has strain relief to eliminate tension on the internal connections and the outer cable insulation extends 1/2" into the box.

If there are specific safety concerns, I really would like to hear about them so I can either address them or abandon this idea entirely.

Thanks,
Mike

My concern is the length of the feeder pigtail. Unless you add some type of extra support (cable tie or tape) the weight of the cord is going to be pulling away from the plug. In other words, the friction of the plug has to hold 12 feet of extension cord in the air.
Title: Re: Ideas for powering LEDs on a bar
Post by: Spenser Hamilton on September 12, 2012, 03:30:43 PM
Well, here's what I came up with.  Not sure it's worth the effort and 6 trips to Home Depot, but it's functional.

We have quad boxes strapped to our light bars, the AC and DMX runs between the lights are zip tied down to look nice and clean (make sure to leave some slack to allow for focus). Haven't had an issue passing inspections with that setup.
Title: Re: Ideas for powering LEDs on a bar
Post by: Steven Leonard on October 01, 2012, 11:19:49 AM
Here are some pics of a project I did a year or so ago. I wanted a Pre wired T Bar with AC & DMX and I wanted a nice clean look.

Hope this helps!
Title: Re: Ideas for powering LEDs on a bar
Post by: Nate Armstrong on October 03, 2012, 03:39:22 PM
Steven,  On those pictures of the T Bar you wired.   do you have a 2 power runs, one for the left two and one for the right 2 light fixtures ?
Title: Re: Ideas for powering LEDs on a bar
Post by: Steven Leonard on October 04, 2012, 01:10:33 AM
Steven,  On those pictures of the T Bar you wired.   do you have a 2 power runs, one for the left two and one for the right 2 light fixtures ?
Yes. I made a "twofer" on each side terminating with two male plugs in the center of the bar.

Hope that helps.

Steven
Title: Re: Ideas for powering LEDs on a bar
Post by: Nate Armstrong on October 05, 2012, 01:29:56 PM
hopefully im not jacking ...    how do you guys transport your 4 wash light T Bars ? 
Title: Re: Ideas for powering LEDs on a bar
Post by: Bradford "BJ" James on October 05, 2012, 01:46:38 PM
hopefully im not jacking ...    how do you guys transport your 4 wash light T Bars ?
Bags here.
Title: Re: Ideas for powering LEDs on a bar
Post by: Steven Leonard on October 06, 2012, 11:48:52 AM
hopefully im not jacking ...    how do you guys transport your 4 wash light T Bars ?

In the back of the truck. All other equipment is in roadcases in the trailer. I unplug the connectors of course.

thx
Title: Re: Ideas for powering LEDs on a bar
Post by: Nate Armstrong on October 08, 2012, 09:00:47 AM
i just put mine in the back of my van or trailer on top of a flat surface.They are the only things that don't have cases. Just wondering if anyone hung / mounted there T bars to there trailer / vehicle. I had thought about installing clamps in my trailer and hang the T bars from the ceiling.
Title: Re: Ideas for powering LEDs on a bar
Post by: Steven Leonard on October 08, 2012, 12:00:24 PM
i just put mine in the back of my van or trailer on top of a flat surface.They are the only things that don't have cases. Just wondering if anyone hung / mounted there T bars to there trailer / vehicle. I had thought about installing clamps in my trailer and hang the T bars from the ceiling.
I have actually thought about doing this too! Has anyone done this successfully? If so PLEASE post pics! thx