Distributed I/O

I was recently contacted about some very experienced controls engineers who had ran into a strange issue. They had come across a firmware problem with one of Rockwell's 1734 Point I/O modules, but weren't having any luck successfully upgrading the firmware. Actually, it was worse than that...

I recently became aware of an issue with the 1734-OE4C not holding late state. If you use this module in an installation in which holding last state is important, you'll want to read the following. As I described in Monday's blog,...

There are some control system applications where system outputs must hold last state in the event they become physically disconnected from the controller, or if the controller stops controlling those outputs for any reason. These applications include some heating, cooling, and pumping applications where the...

Mid-morning of the first day of Automation Fair 2013, I had the fortune of participating in a show floor meeting with Dexter Long, the CompactLogix product manager for Rockwell Automation. The meeting was to discuss the newly announced (and long desired)...

When designing or upgrading a system which relies on a network, bandwidth is always a concern. But for Rockwell's CompactLogix and ControlLogix on an Ethernet/IP network there is a free, easy to use utility to help you size your system. Rockwell's Ethernet/IP Capacity Tool: UPDATE 06/01/2018:...

A client recently asked me if multiple CompactLogix (or ControlLogix) processors could control the same Ethernet I/O. Since RSLogix5000 has supported Ethernet I/O, its been possible to setup two processors to control, or "own," the same remote rack of Ethernet I/O....

Getting hard physical copies of manuals and documentation for Allen-Bradley and Rockwell Software products:   Click here to read part one of this article Yesterday we discussed how to get electronic copies of Allen-Bradley (A-B) and Rockwell Software (RS) manuals and documentation....

When using new products from Allen-Bradley or Rockwell Software, you’ll likely need to refer to the product documentation and manuals for product details. And if you still have the box the product came in, you’ll often find an installation...

I was recently called into a “consumer goods” plant to look at a communication problem with Point I/O. The night before I was told all the Point I/O, which had been successfully tested overseas, was no longer working. However, when I arrived on-site the problem was...