So I'm using this combo HMI/PLC from maple. So far, I really like the interface, but I'm having a problem trying to get something set up. I have around 20ish PID controllers on an RS-485 network. When not in use, the controller is powered off. The issue here, is that even with a low timeout setting, there could be a quite noticeable delay when using the HMI due to all of the timeouts from the process controllers that are not currently in use. I would like to use the contacts I put on the power switches to determine if a controller should be read from or written to, but I cannot do this if there is no way for me to manually check an input prior to sending any data.
Does anyone have any experience with this? My RS-485 network is already in place, and if I can't find a solution, I may have to send this back and pick a different setup.
Does anyone have any experience with this? My RS-485 network is already in place, and if I can't find a solution, I may have to send this back and pick a different setup.