1756-DNB configuration button

[Conor 4]

Hi guys, We had an issue today where we were getting comm's errors on one of our DeviceNet loops. It is one of two loops on the only ControlLogix that we have on-site. We have many other CompactLogix, SLC's, MicroLogix and PLC 5's. Anyway during the troubleshooting process the "Configuration button" was pushed a couple of times. This was pushed as it was thought that this was a "Reset" button. Anyway, we changed out a compact block that was faulty. We then noticed that another node was not coming back onto the network. We did a bit of investigation and found that the node of the scanner card had been changed, from 0 to 2. We couldn't understand how this had happened. We thought that there was a fault on the PLC. Anyway we got out the laptop and were about to start to download etc when we looked at the card again. Then we saw that the button was in fact a configuration button and not a reset button. We were then able to change the address back to 0. This button was pressed by a very experienced guy, but how do I stop this from happening again?? Is there a way to "Disable" this button?? Thanks, Conor

[schui 0]

Conor are you sure you have a 1756 DNB I have never come across this configuration button

[Steve G 1]

Just pulled up the manual, to make sure i was not smoking something. I to do not see a reset or config button on the card, just the switches to set baud rate and node address.

[fuzzy logic 0]

Conor is right, on older -DNB modules there was a manual configuration pushbutton inside the module's front door. It has been removed since hardware series C, if I can remember well. Anyway, the sad thing is that it cannot be disabled; there is a KB technote for that: #45257 - fuzzy logic Edited 19 Oct 2011 by fuzzy logic

[Conor 4]

Thanks for your help Fuzzy

[schui 0]

Its a pity you didnt specify your harware more clearly