S7-400
What are the upgrade options from S7-400 PLC ?
We currently have an S7-400 PLC installed in our plant since 2013. There is a push to now upgrade this system, but it is still performing well. There are concerns about its longevity and its availability on the market for the next 10-15 years. Would you recommend buying a spare system with PLC and IO modules of the same version or a move to the S7-1500?