AB- PLC Hardwiring Interface using Din Rail IFMs


Thread Starter


Has anyone used the Interface modules from AB or Weidmuller that go with PLC5 or SLC 500? I am looking for some help in this area, the selection is complex and I am not sure if its a good idea..any thoughts?
Are there any other vendors making these IFMs?
What about the prewired cables are they useful? How much do you think it will add to my cost if i used IFMs instead of Din Rail Terminal Blocks?

thanks for your time

The slection for the A-B products is a lot easier if you get the configurator tool called RAISE. It steps you through thefrom the PLC I/O
module to the IFM's and prewired cable that is required. A lot easier than looking in the catalogs.

P. Ongert

Gerald Beaudoin

I have been using these modules for a couple of years and have found them to be very cost effective, compared to the time and cost of hardwiring to terminal strips and the chances of errors and the subsequent de-bugging. You ARE RIGHT...the selection of the proper cables and modules is not obvious.....the fact that there were errors in some of the catalogs sure didnt help either. If you can get the latest catalog and get to know how to find the right numbers....I figure they're worth it.

Gerald Beaudoin

Bob Peterson

I have to report that my first (and last) experience with using them was totally unsatisfactory. Maybe we got a bunch of bad ones or something, but the connectors would work loose just enough that sometimes one or more signals would not get to the terminal block through the connector. This was not always obvious from looking at the connector and was a major debugging hassle. We ended up super gluing a fair number of the connectors into the sockets so they would not come loose again.

As for the cost, you can figure out what terminal strips cost to add and the labor to put them in. I figure its some where in the $100 range for a 16 point module. If the IFM stuff costs more then that, why bother? Keep in mind that the terminal configuration (no commons for one thing) on an IFM module is not very well suited for field device connections, so you will end up having some terminals anyway, so why do both?

The other issue I have with them is that the terminals are so small they are difficult to use with normal size field wiring.

Bob Peterson