rs232 through slip rings?

[joe818]

I have a Micrologix 1000 on the moving end of a crane. Power and discrete i/o are transmitted to/from the Micrologix through slip rings. Can I run 232 communication to the Micrologix through the slip rings?

 

[djs]

Hello;
Yes you probably could. However it might be more cost effective to use an unlicensed band data communications radio. These can be purchased for about $900 each or less. High quality slip rings could cost you more.

 

[plcsavvy]

I would only use slip rings, In an application that did not require data to be transfereed while the machine was moving.
If the machine is moving during data transmission, I woul opt for a frequency hopping spread spectrum radio transmitter and receiver. This type of data transmission transmits data over multiple carriers on different frequencies. The first packet of data is transmitted over carrier one for example, the second data packet is transmitted over carrier 2 and so on. Best regards, PLCSAVVY

 

[joe818]

Thanks for the fast reply. The part of the crane that I am trying to communicate to is a small retrieval unit that "tunnels" into a rack storage system and picks up pallets of product(food). Could anyone recommend a radio that is smaller than 3"x4"x6". One that is very durable, has a 200' range through product, can coexist in a small control box with 480V motor starters, and isn't 2.4GHz.

 

[RAGEE]

Just a short note about slip rings.
I have been working with some machines that are using slip rings to transmit data Whilst I have not investigated exactly what protocol it is I do know that it is very reliable & a critical part ot the process. The rotational speed is approx 20 rpm. The main plc siemens s700 communicates to a s400 on the wheel via these slip rings I suspect that the protocol is similar to AB DH+ on the rare ocation that comms is lost the machine intiates a shutdown process coasts to a halt where it waits for the operator to restart it. works a charm.

 

[robertjo24]

joe818,

Try looking at the MDS Transnet radio,

http://www.mdsroc.com.

This radio is small, power efficient, 900Mhz spread spectrum, and built for harsh environments.

 

[joe818]

Thanks to all for the help. The MDS radio looks great. I am also looking at the OS2400 radios from locusinc.com

 

[gigahertz]

If you can convert your data to fiber, there are several styles of fiber optic rotary joints available that may meet your needs.