Modifying existing application

[sNuuFix]

Hello, as far as I understand, It's not possible to edit application that is already in PLC, but maybe there is a way? Company I'm working for wants to fix some bugs in application that has been installed for some years in Vision 350, but the person who did first time setup and has all project files, unfourtanetly have passed away and there is no way to get project files now. PLC block is in active cogeneration station and controls three valves that has to be switched every 6 hours or things will get severly damaged. Time for fixing them is short and making it all from scratch is out of the question.

[Michael_P]

HI sNuuFix,

Your understanding is correct, you can not upload the application if the initial download did not allow for that option. The password protection for an upload application cannot be retrieved or worked around. If you are aware of the actual MI values or para maters that need to be corrected you can change them through info mode, But if the values have a power up condition it will revert to the original value when power cycled. If programmed as a constant value, this cannot be changed unless modified in the logic of the application.