Profibus cable


Thread Starter


We are planning S-7 300 24 VDC plc to control barge unloader operation. It has flexible cables travelling through fastoon cable trollies to operator cabin where the profibus station is installed. Distance is 225 mtr. My question is that whether we can use profibus cable where the cable is subjected frequement movement and tention applied pulling and pushing. Incase of fault in profibus cable will the system malfunction and collapse. One more doubt - can we use wireless connections in place of profibus. i/o 50 nos 4-20 mA 6 nos counter 2 nos. PLEASE ADVISE


James Ingraham

Standard Profibus cable will not stand up to this. However, InterlinkBT and Olflex both make a high-flex version of Profibus cable. I believe Olflex has a high-flex outdoor cable as well.

I wouldn't put much faith in wireless, though it depends on what you're doing.

Hope that helps.

James Ingraham
Sage Automation, Inc.
Siemens has 3 types that should work fine for your application.

FC trailing cable-6XV1830-3EH10
Festoon cable-6XV1830-3GH10
Flexible cable-6XV1830-0FH10

All are for profibus. But instead of the standard solid conductors, these are standed. Also- Use ferrules on your wires when using the
profibus connectors.

Donald Pittendrigh

Hi All

I could supply you with appropriate festoon cable for a heavy duty flexible application like this, I am also sure your local cable agents or even Siemens could too.

If the cable is damaged, you have the option to program the S7 to do whatever actions you need to ensure the safety of the machine, I think by default it will put the PLC into stop mode, but by use of systems diagnostic OB's, I am sure you can set it up to produce whatever type of reaction suits the machine best.

I have not yet found an affordable radio system that can handle Profibus suitably. There are applications of Profibus which run on radio, as far as I know the bus system has to be manually de-tuned in order to accomodate radio "transmission delays" in the token passing monitoring. This is not advisable for the type of application I think you are setting up. Perhaps some of the list members know what is happening to the Rfieldbus spec which has been very quiet for a while now.

Siemens makes a Profibus transmission system using infra-red, but its transmission distance is only 15 metres, perhaps you could run flex cable to the hinge point of the boom and then span the worst bending area of the cable with this device. Perhaps also if you look around you may find a similar device with a longer distance.

Is the boom of this machine 225m long or is the operator cabin at ground level, it sounds very interesting, where is the machine being built. I could show you a few container cranes and grab unloaders, shiploaders and similar using Profibus in my area if you are interested, but I am in South Africa.

Donald Pittendrigh


Phil Marshall

Consider Profibus over fiber, glass does not have the problems of copper in such applications