HOW TO COMMUNICATE WITH 1794 ASB FLEX IO using SLC 500 Program

[moe2016 0]

Hi, I have just started working on a technical project and needed some assistance with connecting to my application. I have started to build my program using rslogix500. The project contains 6 neumatic actuators, all with advance and retract features. All the air lines and presasure regulators are already set up, I am just building the program, connecting to the PLC, and creating an HMI panelview interface. I am having some trouble connecting to the plc, this is the equiptment I am using: Omron power supply AB flex i/o RIO adapter 1794-ASB 2 x 1794-OA8 outputs 1 x 1794 IB16 inputs We are trying to connect to AB slc-500 scanner 1747-SN to communicate with the AB flex RIO adapter. I wanted to know what instructions i will be using on my SLC 500 ladder logic in order to communicate with the Flex IO 1794 ASB series E adapter?

Edited 29 Jan 2016 by moe2016

[Ken Roach 194]

Welcome to the Forum !

First, get yourself over to the RA literature server:

http://www.rockwellautomation.com/global/literature-library/overview.page

Download the 1747-SN user manual and the 1794-ASB Series E user manual.

The 1747-SN appears as 32 words of Input data and 32 words of Output data in the SLC-500's Input and Output data tables.

You will set up the 1794-ASB to be "Rack 0" starting at "Group 0" with Standard addressing, using the DIP switches.   The User Manual explains it all.

The 1794-ASB will be considered a "1/2 Rack" of data, using up the first 4 words of the Input and Output data tables for the Slot number that the 1747-SN is in.   That's the data size that you will set up in the I/O Configuration section of RSLogix 500 when you configure the 1747-SN to "scan" that 1794 adapter.

 

Edited 30 Jan 2016 by Ken Roach

[moe2016 0]

I'm sorry i haven't been quite clear i wanted you to give me a grasp about what instruction i would use on the SLC Ladder logic. I was guessing a SQO instruction , however i was still unsure. 

 

thanks 

[Ken Roach 194]

You generally use ordinary Output instructions, e.g. the OTE instruction.

SQO is nice when you're running a sequencer, but for ordinary ladder logic you just use the OTE.    It looks like a "coil" in ladder logic:

--------------------( )----

[kaiser_will 65]

As Ken Roach has guided you to, when you build your new SLC program and add the SN module, RSLogix will create an I/O structure of 32 words in and 32 words out.  Since this SN module can communicate with a lot of I/O, the ASB module at the other end will only consume 4 words in 4 words out.  These 4 words out (from SLC to ASB) will have your output coils.  Read through all of the literature.  Since your remote rack has simple discrete cards, your logic will have contacts and coils that will be bits from these 4 words in and 4 words out.  I suggest start simple having only 1 input channel on (such as the terminal tied to 24VDC) then look for that bit to be 1/on in the SLC data file; lift the 24VDC and verify the input turned off; then move onto outputs - toggle output word bits and look at the lights on  your output module to verify they are lit (make sure you have your outputs lifted so you don't accidentally have unintended motion).

[moe2016 0]

 Our Project requires the use of a sequencer since we have 6 cylinders. We are also using 12 reed sensors for the expansion and retraction process because we are moving a block through a path.

[Ken Roach 194]

Okay, fine.   SQO isn't the only way to build a sequencer, or to turn on outputs.

If you want help writing a machine program, post about that.    

I assumed that because you were using a relatively difficult-to-configure set of networked devices that you needed help setting them up.

[saskcat99 0]

Howdy.  I'm an old time user but a new time poster.  Its been a long time since I've scanned these pages.

Nice to see the old names still about.

My issue is with the set up as mentioned above.  I also am trying to communicate with a 1794 asb using an 1747 sn scanner.

There were some 1791 8ar in a JB that i replaced with an 1794 asb2 with an input and output modual.  When powered up, the output modual is updated and follows the instruction of the program but the input modual shows the inputs on the modual, but will not update the ladder logic, or input table as such.

As far as M0 and M1 tables show, all rio is true and active with no faults.

I used a test bed slc500, sn, asb, and i/o and everything went fine.  I moved the equipment to the new location, updated the ladder for the new addressing but the input(s) will not show up on the input table.  

As far as the Rio map,  the new pieces are located at the same place in test unit and main unit.  I just dont get it.   I have went over it a million times.

Any ideas would be greatful.