SLC to Opto22


Thread Starter

Ray Pike

Anyone know how to control Opto22 from an SLC504. Client has old PC based system controlling multiple Opto22 racks via "B1" brain boards. Client wants to replace PC with SLC504, but wants to keep existing Opto22 I/O.

Thanks, ray pike
I had a customer in the exact same dilema. I had several options but after talking with several Opto 22 integrators that I knew it was clear that the best thing to do was the following:

Migrate the B1 cards to B100 cards and purchase an Opto 22 controller (SNAP-LC Controller) that is equipped with a Modbus Integration Kit and or AB Integration Kit. Then your SLC can talk to the Opto 22 controller as a slave.

However, if I were in your case I would reconsider using the SLC to begin with. From my experience I have found it much easier to simply tie the equipment back to an Opto 22 controller. In the cases where the SLC controller was absolutely required by the customer I've taken the route I mentioned above.



I don't think anyone ever made a Optomux scanner for the SLC-500 family, so you'll need to go to another communications medium.

If your existing system uses only the digital B1 brain boards, you can probably drop in Opto-22's own BD-DEVNET brain board. It's a DeviceNet
slave adapter that's a straight-up replacement for B1's on the classic Opto racks like the G4PB16H. You'd use a 1747-SDN DeviceNet scanner and you'd have the ability to use other native DNet interfaces like drives and serial interfaces and the like.

Opto-22's BD-DEVNET is only for digital I/O. You might want to check out the products made by Western Reserve Controls ( for re-use of Opto-22 style I/O modules on DNet and Modbus.

You could probably also use a Prosoft Modbus scanner in the SLC chassis and use the Opto-22 Modbus slave adapters to replace the B1's. This might enable you to use the existing wiring.

Either way you're going to give up some of the Optomux protocol commands.

Good luck,

Ken Roach
A-B Seattle
[email protected]
If it is Optomux, which is serial based, you could either use a Basic module or use a SLC 5/03 or higher with an RS-232 port and built in ASCII
instructions in ladder. I would try the built in ASCII instructions first. Write a subroutine to read a string from a file and send it to the
I/O. Be sure to use error checking and test all responses for reliability. I hope that this enough info to get started. It is a doable
project, but it is not easy. I would try it, but that's me. If you are not familiar with ASCII codes and serial comms, you are in for a real learning curve.

Bill Sturm