Control on a rotating drum


Thread Starter

Zach Frey

Hi all,

I have an application that involves a rotating drum, and the possible need to place sensors and actuators on the drum itself.

Does anyone have any experience with something like this? I don't understand how to manage wiring to a piece of rotating equipment. Any pointers or recommendations would be greatly


Zach Frey

List Management Account

I would suggest that you use slip rings, but you might have to attach a shaft, so the core of the slip ring rotates with the drum. The wires from the rotating part of the slip rings go to the sensors on the drum, and the wires from the
fixed part of the slip ring go to the control circuit.

I buy slip rings from a machine manufacturer in Taiwan, and I wouldn't know where to get some in the U.S. Maybe somebody else can help with that. But if you need information on my supplier, contact me and I will be glad to help.

Jorge Delgado
[email protected]
Hello Zach-
I've had quite a bit of experience in the field of Motion Control and one of the applications I worked on involved a scenario similar to yours. In this application, the customer had a need to mount 48 axes of servo drives and controllers on a turret that rotated continually as part of the process. They solved the problem by using a slip ring. The slip ring is essentially a custom designed mechanical "switch". Envision a drum on a player piano or a music box. The song is played by encoding the song notes onto the drum. When the actuator passes over the notches on the drum, the notes are played. Same deal here, except that in place of the notes for the song, you will have I/O on and off points encoded onto the ring. The drawback, of course, is that it is not very flexible. Communications were handled by a wireless RF receiver/transmitter arrangement. Hope that helped.

Pete Arthur
Emerson Drive Solutions

Riti Francesco

Try to use slip rings. Slip rings allow to transmit electrical/pneumatical connection from stationary to rotating parts as a drum.
Try to contact ELETCA

ELETCA produce slip ring, without any mercury inside.
I use the 4 contacts type in high speed packaging applications.

I hope this could be useful.

Francesco Riti
Automation department
Eurosicma - Italy

Gene Wilkins

Hi Zach;
I'm sure you have gotten a lot of suggestions regarding the use of slip rings, etc., . But what I would suggest you take a look at is the Balluff
power remote sensors. They transmit the status of multiple sensors through an air gap.

Gene Wilkins,
CALL Associates Inc.

Burda, Jason M.

I don't know all the specific, but if all you are trying to do is control a process based off the position of the drum, have you considered coupling the drum to a encoder/resolver for feedback and controlling that way. GEMCO (as
they were called in 1996) manufactures a nice programmable limit switch that sets 24 VDC outputs up to 72 (expensive option with so many outputs) depending on the position. Of course, if you have a PLC already available, you can just install a feedback card/block and run one cable from the encoder. The main problem I ran into was lack of a good mechanical design for linkage with the drum and the resolver.

Let me know if you have any other question.
Omron has an inductive coupler which can transmit power and I/O signals across a gap, so there would be no solid wires across the rotation. It's in their sensor catalog or look it up on


Rob Entzinger Schneider Automation

Put a small PLC on the drum use slip ring for power and radio comms to the base station.

Rob E.

Blake Burgess Averydennison

Use a slip ring assembly, there are many manufacturers. One I have used for many years is Wendon Co. from Conn.