Control Logix system with "plug and play" I/O design required

[dtomilenko]

I am looking for a general way of making a Rockwell Control Logix system be able to automaticcally know what devices or instrumentation is installed in any of 10 bays. These bays can be the same or different and can be placed at any of the 10 locations. I want the control system to sense and reconfigure as the bays are located and plugged in.

Should I consider a different control system? Have you built a PnP machine?

 

[xyzz]

What may be a practical use for this?
And what the software can do upon such recognition, if one is possible?

 

[modernbiomedical]

What I have done in the past for my systems to recognize what unit is pluged in is by a resistor of different sizes issued to different units when plugged in, it would sense the resistance go to the look up table then it would automatically run the software associated with the resistance. This wa with micr-controllers. A way you could do with a plc, i have also done this a few times, is by giving each device a binary code of say 0000 to 1111. This would give you 16 different devices. Then wire up each device so that when plugged in would send a binary number back. This would use up a maximum of 4 inputs on your plc. In order to do this you would have to have at least a 5 conductor connector. One of the conductors would be the (vcc) or the like from the input of your plc. This is usually used to run through dry contacts and back to the inputs. Then wire the other 4 on the connector attached to the device to the (vcc) so that the output would be the binary code. Then send these back to the plc on input 1, 2, 3 & 4.

PLC should then see a 4 digit input. You could say if input 1, 3, 4 is on (1) then run the saequence for device number 11. I hope this was helpful. It is easy to do hard to explain. If you need help I can be reached at biomed@cox-internet.com

Female connector Male connector on our device
>--(vcc)---> >----(vcc)------|
1<--(in 1)--< <---------------|
0<--(in 2)--< <-----------X | don't connect (open)
1<--(in 3)--< <---------------|
1<--(in 4)--< <---------------|

This would give you a 1,0,1,1 on the plc (11).

Sincerely
Roy Morris