Analog input read issue SLC 505

I have a site with SLC505. The analog card is working but the ladder program is not sensing any analog inputs. It will be helpful if any one can share some light on what problem might be happening here. This is an emergency and early reposne is appreciated.

Thanks

Welcome to the forum.

How do you know that the analog card is working? We really need a lot more detail in order to help you. Can you post a copy (zip the .RSS file and attach it to a post) of the program?

Also, please tell us what analog card it is.

Welcome to the forum...

You'll need to provide more information.

I don't understand the comment " The analog card is working but the ladder program is not sensing any analog inputs", how do you know the card is working if you can't verify it in the program?

What have you checked? Off the top of my head..

1. Dip switches, 0 - 10V or 4 - 20mA
2. IO Config
3. Are you calling the ladder routine? You didn't forget a JSR in your logic?
4. Scaling?
5. I/O addressing incorrect?
6. Have you verified you are receiving 4-20/0-10 signal at the card?
7. Field device powered up?

Analaog card SLC 505 issue

Attachment has the zipped .RSS file.

Thanks for your immediate reply.

The Allan Bradley guy checked and said the analog input card is good and receiving signals from sensor. Th PLC was running good until recently when the attached program was reloaded. And we do not have the copy of the old working version.

Currently when i go online to the system, the analog inputs are all showing zeroes. The AB tech guy said it has got something to do with config issue.

I am new to this SLC system and am trying to fix it. The calibration for inputs is -20 - 20 mA instead of 4 - 20 mA. Is this could be a reason ? Also how to check if PLC is communciating with analaog card ?

You have not configured the analog card and none of your analog input channels on the card are enabled. Refer to the manual for this card at http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1746-um001_-en-p.pdf

Also, do you really need to configure the card as a class3 card? You aren't using any of the advanced class 3 features, you might want to delete it and re-insert it as a class 1 card since it is a lot simpler to work with.

Logix500 has a configuration tool that will help you configure the card. Select the card under IO configuration and pick Adv. Config. Then pick Configure. Set up each channel you are using. Then click OK. RSLogix will suggest an N file number to store the configuration in (Probably file 10 for your program) It will show a rung to be inserted and suggest a location at the top of the program 2. If this is good then click OK. RSLogix will insert a rung that will configure your card for you on the first program scan.

Thanks a lot guys for the help. I am gonna look into the system tom when i am in the site and try enablign and configuring the input module.

I will post my status tomorrow.

Thanks again

- K

Analog input enable

I enabled the analog input card and it worked. Your prompt response meant a lot for me !!!!

Thanks