AB SLC5/05 with RIO scanner

  • Thread starter Michael R. Batchelor
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Thread Starter

Michael R. Batchelor

Can anyone tell me if there is some special "trick" to get a SLC5/05 with a 1747-SN RIO scanner module to talk to a 1794-ASB module that has a couple of Flex I/O modules on it?

We use several SLC5/04's with the 1747-SN to talk to some RIO Panelviews successfully. And we use the 1794-ASB plus FlexI/O modules with PLC5's successfully. Some of the documents on the AB
site list the 1794-ASB as a legitimate device to use on the SLC5's with a scanner module, but so far we're scratching out butts trying to get them to work.

I've got the G files, etc. set up exactly like the ones with RIO Panelviews, and the ASB module set up for Rack 0 Group 0. 230K. Cable is about 3 meters. Terminating resistors right out of the
factory package.

All the hardware seems to work fine in other units. Can someone please give me the "a-ha" piece of information I'm missing? I'm starting to doubt my own judgment.

Michael R. Batchelor - Industrial Informatics & Instrumentation, Inc.
We have several SLC 5/04 installations running with 1794-ASB's and Flex I/O. A couple of things come to mind: Are you using discrete Flex modules or analog? You have to use block transfers for analog modules since there is only one word allocated in the scanner for each Flex module. Also, in the G file, the ASB size is determined by the number of terminal bases attached to the ASB. One or two bases equal 1/4 rack. Three or four bases and it's a half rack and so on. If you are trying to allocate more space to the ASB,
perhaps for future expansion, you'll have to install at least the terminal bases up front. Keep in mind also that the only way to allocate more space in the future requires taking the processor to program mode and reloading the program. You can't change a G file online.

Danny Michael

Bob Desrochers

One thought that comes to mind is (at least in the PLC-5 series) you can not assign a 1771-ASB scanner to rack 0. That rack is used exclusively by the processor chassis. If the SLC5s live by the same rules then changing the rack assignment will get it off the ground.


Eduardo Manuel C. Cipriano


I have been with AB for 4 years as a Sr. Automation Engr. for Tech Support

Try to check your Series or type compatibility of your ASB and RIO Scanner they dont work if you dont have the right compatibilty series this are posted in AB.com website ...........

anyway if you have additonal questions you can email me at:

[email protected]

Eduardo Manuel C. Cipriano
Sr. Systems Engr.
Yokogawa Phils. Inc.