In search of 360 rotating power source.

[SweetBennyFenton]

Hello all.

The current show I am working on mostly consists of a 12'x12' turntable that the set is built on top of. We need to to run a single circuit of constant power to that unit without hindering its ability to spin. Current idea is to drop a single cable to the center of the unit from above and just make sure that cable can rotate.

I originally thought that a freely rotating, locking power coupler would be out there somewhere, but I can't find a dang thing. Have any of you ever found something like this? How do you electrify rotating scenery?

Any advice would be greatly appreciated.

 

[JimmyM]

What you are looking for is a slip ring, however, they can be very expensive for mains rated use. Before you decide you need wall power, look into using a car battery/wireless dmx/inverter setup, just charge the battery between shows. If you need more current than that can offer slip rings may work, albeit at a cost.

 

[RC4Wireless]

I agree with JimmyM. And in many cases you can use low-voltage light sources and avoid the inverter entirely -- it's bulky, inefficient, and often noisy as well. We have a wide range of DMX-controlled wireless dimmers, all the way up to a 500W unit that fits in your hand. Check out the whole family of 900Mhz wireless DMX and dimming. We've done entire touring shows this way, with numerous rotating and mobile set pieces all over the place.

Jim
RC4

 

[porkchop]

I've used RC4 wireless dimmers with car batteries before to prevent this issue. It's a lot cheaper solution than a slip ring or slew ring. The cable through the center can be problematic if rotated too far in a single direction. If you have to go that route I suggest using Retracting Cable or something similar as it's a bit sturdier that common SOOW.

 

[SweetBennyFenton]

Thank you for helping me put a name to what I'm looking for. Now if I could just find one of these already built into an extension cord or receptacle, I'd be set.

A retracting cord would make a good plan B.

We had originally looked at using a battery for the power source but some of the equipment we're using needs 110v. *sigh*

 

[soundman]

How about a 10 amp slip ring for $30? https://www.sparkfun.com/products/13063

 

[Amiers]

I've used RC4 wireless dimmers with car batteries before to prevent this issue. It's a lot cheaper solution than a slip ring or slew ring. The cable through the center can be problematic if rotated too far in a single direction. If you have to go that route I suggest using Retracting Cable or something similar as it's a bit sturdier that common SOOW.

You could do that or if it is actor controlled a 900w 12 120 inverter would work the same and again would use a car battery. As a redundant solution you could throw a RC4 in to the mix.

 

[RC4Wireless]

How about a 10 amp slip ring for $30? https://www.sparkfun.com/products/13063

Now THAT is a great find! Thanks for pointing this out, soundman!!

 

[RonHebbard]

Hello all.

The current show I am working on mostly consists of a 12'x12' turntable that the set is built on top of. We need to to run a single circuit of constant power to that unit without hindering its ability to spin. Current idea is to drop a single cable to the center of the unit from above and just make sure that cable can rotate.

I originally thought that a freely rotating, locking power coupler would be out there somewhere, but I can't find a dang thing. Have any of you ever found something like this? How do you electrify rotating scenery?

Any advice would be greatly appreciated.

@SweetBennyFenton Back in my automation shop days ALL of my slip rings came from UNITED EQUIPMENT ACCESSORIES Phone: (319) 352-3946. They had no stock products everything was custom. They had two or three stock diameters and had slip rings for electricity and the equivalent devices for pneumatics, and liquids. You detailed what you wanted and waited for them to produce it, one assembly at a time, just for you. Not cheap but affordable. Not fast. From memory, approximately a 3 month lead time was required.
Again from memory. At the small end of their products, you had maybe about a 3" diameter clear space up the center.
At the large end, they made slip rings for fire department aerial ladder trucks which had rings for lights on the ladder as well as slip fittings for fire fighting water under quite high pressure as well as slip fittings for electrical, pneumatic and hydraulic controls operable from the bucket atop a forty to sixty foot ladder. You placed your order and waited patiently for delivery. The large rings for fire trucks cleared maybe 30" to 36" through the center. There were one or two diameters in between. They were never quick but they were ALWAYS on time. They'd quote a delivery date when you placed your order. They never arrived early but they NEVER missed a shipping date.
Short version: They were GREAT to deal with. For me, this was in the early 90's. 1992 to 1996 or so. They were SO good to deal with, I still have their name and phone number in my PC.
Toodleoo!
Ron Hebbard.

 

[Les]

How about a 10 amp slip ring for $30? https://www.sparkfun.com/products/13063

Hmmm.... 3 wires... I'll bet you could run DMX down that if you are brave enough. I wonder how reliable that would be? Apparently it is compatible with data and bus protocols.

 

[rsmentele]

+1 for giving UNITED EQUIPMENT ACCESSORIES a call!

Called them and got a ton of help finding something that will work for me that was in stock and not custom, so it saved me time and money!

I got a 4-20A circuit for $178.

This was for putting lights onto a revolve as well.

The best part is... it's made in the USA, not some unknown factory overseas with questionable QC and lead times

 

[RonHebbard]

+1 for giving UNITED EQUIPMENT ACCESSORIES a call!

Called them and got a ton of help finding something that will work for me that was in stock and not custom, so it saved me time and money!

I got a 4-20A circuit for $178.

This was for putting lights onto a revolve as well.

The best part is... it's made in the USA, not some unknown factory overseas with questionable QC and lead times

@rsmentele Assuming they're still producing their same quality, you're going to love it when you receive it. Built to last and built to be serviced / maintained. Assembled with real hardware, no glue and rivets. All the rings we bought from them were absolutely first rate. We built the large, automated, pinball machine for the Who's Tommy three times. The big pinball contained three axis of Reliance AC servos. One of the AC servo's was powered via slip rings; the motor power, its resolver leads, a DC brake, a couple of absolute limits and low voltage for pyro. All via a custom assembled set of rings combining rings for AC, DC and data levels. Good people. Can't say enough positive about them. Please let us know your further thoughts once you receive your rings. You wrote: "I got a 4-20A circuit for $178." Is this four hots, four neutrals and a common ground or? How many poles in total and I'm assuming AC.
Toodleoo!
Ron Hebbard.

 

[rsmentele]

3 Hots, a shared neutral and ground.

I purchased it about a year ago for a show. Worked just as needed!

 

[RonHebbard]

3 Hots, a shared neutral and ground.

I purchased it about a year ago for a show. Worked just as needed!

@rsmentele What diameters, both clear through the center and overall by approximately how high? I'm understanding five rings from what you wrote. Did you buy it raw, un-wired and unhoused or did you purchase pre-packaged within an enclosed housing? We were always purchasing raw as we were building them into tightly confined spaces within mechanics. They thought we were a little odd never ordering enclosed assemblies. Granted, we probably were / are a little odd but that's a different discussion. Reliance Electric, the manufacturers of the AC servo drives we were using, thought we were daft to consider running their bridge power and their resolver through slip rings but we did it at least three times with never a hint of trouble using rings designed for different power and signal levels custom assembled within one stack. Granted there's a difference in positioning accuracy required between a giant rock 'n roll pyro-spitting pin ball machine and a precision controlled tool post on a lathe.
Idle curiosity. How did you first hear about United Equipment Accessories?
Toodleoo!
Ron Hebbard.

 

[rsmentele]

I misspoke, it was a 4 circuit. We purchased an off the shelf model as the ETA fit in our time frame. I still have the .pdf! (attached)

I got enclosed for safety as it was a high school show, but they offered the same model without the enclosure too. Of course, since I was building the set and could fit the mounting around whatever slip ring we found, I was able to be flexible on size/diameter.

I found UEA from some google searching. I initially was only able to find manufacturers off shore, but happened across them after digging a little more. Submitted a simple online quote request and I got an email back shortly after. Told them what I was doing and what I needed and they let me know the closest off the shelf option they had as lead time for a custom piece was about 6 weeks and custom was 2-3 times more expensive too.

All in All, super easy and very helpful company!

 

[DGotlieb]

Current idea is to drop a single cable to the center of the unit from above and just make sure that cable can rotate.

If you choose to use cables and not battery, you can run your power discretely under your revolve. You just have to attach your casters to to stage floor with the wheels up and then put the revolve on top.

Also if you only do 1 or two rotations and then able to rotate back you can usually just get away with a simple cable and nothing fancy.

The only thing you have to worry about is your pivot point.

 

[RonHebbard]

If you choose to use cables and not battery, you can run your power discretely under your revolve. You just have to attach your casters to to stage floor with the wheels up and then put the revolve on top.

Also if you only do 1 or two rotations and then able to rotate back you can usually just get away with a simple cable and nothing fancy.

The only thing you have to worry about is your pivot point.

[& the Fire Marshall, the electrical inspector, your reputation and the point on your head you're pivoting on.]
@DGotlieb @SweetBennyFenton You, of course Sir, in a perfect world are perfectly correct so long as your world retains perfection and IF your string of "ifs" don't get you. You know what "they" say about making things idiot proof and the world providing ever more occupants attaining higher and higher levels of idiocy. Welcome the opposing worlds of expedient vs idiocy.
Toodleoo!
Ron Hebbard