Remote IO

[TOMC]

I am looking at adding 2 compact block IO modules to an existing RIO network. This is no problem to do. I was going to mount the IO on 2 sets of tooling. Is it posible to unplug those nodes from the network when a tool change is done?

 

[Steve Etter]

Not knowing what PLC you are using, nobody here can say for sure, but I do know that some PLC's allow you to set up remote nodes so that communications loss will not cause a shutdown. Others won't have this option. Look for a setting that lets you dictate how the system will handle a node communications loss.

Steve

 

[TOMC]

The PLC is a SLC 503. In the users manual for the scanner card it tells you how to use the M0 and M1 files. There is a Device Inhibit Control which you can inhibit selected nodes from the program but it also says that over time the nodes will return to their last state. I don't know if this will work properly.

 

[Ken Roach]

The main challenge is that RIO is a daisy-chain network that requires termination resistors on the end of the cable.

If you put one of the termination resistors on the removable machine, you will have to connect a replacement resistor to the network when you unplug the removable equipment.

There is also a chance that the whole network will fault when you unplug the removable equipment, because one termination resistor will be missing.

RIO is fairly forgiving, but only a physical test will find out for sure.


If this is a system that shuts down while you are removing gear, then it's no problem. If the RIO network has to keep running even though you've unhooked the end of it... maybe a problem.