Sign in to follow this  
Followers 0
Guest Dark Dog

Changed I/O Card

4 posts in this topic

I changed an I/O card and reset my PLC (SLC5/03). I have it connected to a radio modem for remote monitoring. I replaced the card with the same type and rewire the inputs as it was before and reloaded the program. It works fine, well for one problem, I can't poll it remotely for information. I check teh channel configuration and its okay. Any ideas on what could be the problem. I also verified it gets the poll. Rx lights up. But it doesn't answer.

Share this post


Link to post
Share on other sites
1. Double check the Ch0 settings. Is the version of the program you downloaded the correct one? 2. You say the RX/TX lights are active....I assume these are the ones on the modem. What about the Ch0 light on the SLC? Is it active, if not then you may have a cable fault. 3. Check the +24v output on the SLC PSU...is this still ok? 4. Try swapping things, can you put in another 5/03? another modem? another cable? from a working system. Eliminate these things one at a time. 5. Is the 5/03 battery still OK, if the BAT light is ON it needs changing. 6. When changing an I/O card there was no need to "rewire" the module, the terminal block on the front of most of the 1746 modules is removable with all the field wiring in place. 7. Neither was there really any need to reload the program...the SLC memory is backed short-term by a capacitor and for up to 1 year or so by the battery. No need to reload if ALL you did was power the system down? In that case WHY did you need to reload the program...is there a clue here?

Share this post


Link to post
Share on other sites
8. And one more thing...check that your I/O 24 v Common supply, is still connected right. It is quite likely that it is also supplying the radio modem and if the common is absent or otherwise screwed up, then it might be causing the RS232 comms connection to fail. Bit of a long shot.

Share this post


Link to post
Share on other sites
Thanks alot for all the advice. I changed the radio and all is well.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0