RSNetwork for DN Point IO

[eight_bools]

Hey guys

Im thinking about using some point IO on and old SLC 5/05 with a device net scanner.

I have RS Networx and have looked at some other scanners that we have on other machines to see how it works. I was able to add the 1734-ADN but do not see how to add the IO modules to the IO adapter. I can add the IO modules but they show up with a different node address.

Anyone have any pointers on what I am missing.

[Ken Roach]

POINT I/O with DeviceNet was a weirdly flexible product. The backplane of POINT I/O is really just DeviceNet at 1MB.

When you used a 1734-PDN, the DeviceNet network basically passed the packets straight through to the connected modules. They all took up a whole DeviceNet node number of their own, and you would see them individually on the RSNetworx project.

The 1734-ADN is a different animal: it is itself a Scanner on the POINTBus side, and an Adapter on the DeviceNet side.

So you actually need two different RSNetworx files: one to map the POINT modules into the -ADN's Scanner side, and another to map the -ADN's assembled I/O image into the Scanner from an PLC/SLC/Logix.

You would almost expect to be able to double-click on that 1734-ADN and open up another instance of RSNetworx or an applet to configure it, wouldn't you ? But you dont: you create an all-new project file with the 1734-ADN as a Scanner.

It's clunky at best, which is one reason it's been almost entirely supplanted by the 1734-AENT and EtherNet/IP.

But it does work !

[eight_bools]

Thanks Ken, if I had looked hard enough I would have seen that in chapter 5 of the 1734-ADN manual.

[Ken Roach]

I built a system with what could be best described as "failover" I/O where a ControlLogix Redundancy system ran remote chassis on ControlNet each of which had a 1756-DNB that scanned some special sensors as well as several 1734-ADN adapters. Each ordinary discrete or analog sensor was wired to two separate POINT I/O modules.

So I needed two *.DNT files for the two 1756 Scanners, and a total of six *.DNT files for the 1734-ADN adapters, four of which were identical except for their serial numbers.

Let's just say that when I came back to it after six years I was grateful for 2010-me writing good notes.