ControlLogix DH+/RIO to Flex IO analog module

[IanH]

Hi Guys,

I've been doing some experimenting in the shop and im hoping someone will be able to point me in the right direction.

I was able to get my hands on a 1756-DHRIO/E adapter.

First project was connecting to a 1794-ASB2 Adapter, to read inputs and write outputs.

After some messing with dipswitches I was able to get that to work.

Moving forward i've got an analog card, 1794-IE4X0E2, and this is where I got stuck.

Ive read through 1756-UM514C-EN-P, where it shows you how to set up a Block Transfer Read inside of a message instruction.

However after a lot of reading and trying different things I haven't been able to successfully read any signals and have hit a wall.

I believe the module needs to be configured through a write instruction, again this is where im struggling to find some material with examples.

Any info would be much appreciated.

Thanks!

 

[JohnCalderwood]

IanH,

welcome to the forum.

You are correct, the analog modules require a BTW to set up the config.
if you read the manual for the 1794-IE4XOE2 manual, it gives you the configuration.

But why are you going for the DH/RIO module? Us oldsters use them because we have to, with the plethora of old technology we have in the factories. This is older technology....

Can you post us more as to what your setup is and your rack layout?

 

[IanH]

Hi JohnCalderwood,

Thank you for the reply, I started looking at the configuration in the manual last night so I'm glad to hear I was looking in the right place.

I work as an industrial service electrician, and a lot of our customers have these Dhrio cards / networks in service.

Now that I'm starting to work with our automation group more, I'd like to get a better grasp of how this equipment is set up and how it works. Whether it's upgrading nodes to ethernet, or upgrading a controller and using existing media / hardware I feel it is important to understand what's coming out along with what's going in.

That is what has inspired this little project! I've got an rtd with a 4-20ma head set up on this analog card. I plan on just reading shop temperature and then turning on a fan or a heater depending on the ambient temperature.

I'm going to have another go at it tonight and I will report back with my findings and code.

From what I can tell, writing the configuration to the module is very similar to setting dipswitches, it's just done through memory rather than physically.

Thanks,
IanH

 

[JohnCalderwood]

Aye, IIRC, you have to look at the configuration words for the module, and set the bits for the config, then send it by BTW.
The PLC5 setup documentation that was a user interface, in text form, so that you selected the config, rather than setting the individual bits.
I have a template for the 1794-IE8, as one of the projects that was done here took in a lot of RIO racks with analogs and I had to create a spreadsheet for the maintenance techs, so that if any of us had to add another module, we knew what data words to use and what bits to set/unset.

 

[IanH]

It was a little bit of a struggle but I was able to get the Analog module up and running. The problem I was having was in the setup screen I was pointing to the wrong slot in the rack. I had thought that dropdown was part of the ControlNet Setup beside it.

Once I got the configuration block setup things started to come together. There is quite a bit of information you can pull from these modules; very interesting.

Helpful resources:
(Cat. No. 1794IE4XOE2 Series B)

(Cat. No. 1974-ASB Series E)

PLCS.net

Thanks JohnCalderwood for your feedback

Hopefully this helps someone out in the future.

-IanH