The most common conversation I have with people is about how to make connections between different control networks. My customers have Modbus networks that they want to tie to Allen-Bradley PLCs or Logix controllers. Controls Engineers have to make all of this crazy stuff talk. Profinet to Ethernet/IP to serial to CANopen to DeviceNet to ASi. It just goes on and on and on. I know everyone of you reading this have pulled your graying hair out trying to make a connection between one brand of PLC and another brands favored network. (OK. Some of you aren’t graying yet but others are past graying because I’ve noticed there is little left. But I’m not judging.)
The most common follow-up question I get to “How do I connect the two networks?” is “Why are there so many choices?” My answer is that there are a bunch of different manufacturers and network interfaces in the market but some solutions are more appropriate for certain control applications than others. I’m glad there are a lot of choices. It helps me recommend the right product given the application. For instance, if you want to connect a bar code scanner or RFID reader to an Ethernet/IP network, I have yet to find an easier device to use than the ASCII to Ethernet/IP interface from RTA. There are ASCII to Ethernet/IP devices available from other manufacturers but RTA’s 435NBX is just my personal pick.
So what are some other important considerations when picking an interface?
If you are using a Rockwell Automation controller (MicroLogix, SLC, PLC, CompactLogix, or ControlLogix) and the application allows you to stick the interface in the chassis with the controller, you need to look at ProSoft’s InRax interfaces. ProSoft makes both chassis-based and non-chassis-based gateways for just about any imaginable network connection. If you are using any of the Rockwell Software FactoryTalk View products in the system where you need an interface it’s a no-brainer to take advantage of the faceplates ProSoft developed.
One of the newest devices is the HMS Anybus CANopen gateway. Typically CANopen devices come in to my customers on a machine and need to be integrated into a larger system with a PLC or PAC. The new CANopen gateways from Anybus provide a simple interface to tie a controller (anyone’s PLC) to the CANopen devices.
If you have an interesting application or story about how you were able to tie two or more different networks together I’d love to hear about it in the comments.
Links to other posts covering interfaces for tying different control networks together:
Use SLC I/O (1746) on an Ethernet/IP Network