Andyroo wrote: ↑
Sat Nov 10, 2018 10:25 pm
Only hope you have is a bit off the wall:
1) as above - Stick a camera so it can see the display and OCR it.
2) Program the temp to trigger the relay at your warning temp and pick the relay change up.
Section 3-6 has an example of programming the unit but it also checks for a lower temperature so it will need modifying.
Note as this is a ‘C’ model, you only have one relay contact and that may be needed by the plant so you need to check with the plant engineers to see how you tap in and feed an opto-isolator and then to the Pi. Without a lot more plant details I doubt folk would want to advise you on the relay link just in case
Best bet - replace it with a more modern unit that can interface to others...
Thank you, Andy.
I could maybe just set a much lower temperature that wouldn't be reachable. I only need the trigger at like above 70degC. The plant only requires the visible temperature on the unit, so I'm free to use the output for the relay.
I'm not familiar with opto-isolator. Does it have the same function as a breakout board? I looked it up and it seems to be safer but complicated for me to use I think.
I intend to use MAX31855 with a separate K-type thermocouple probe if it didn't work out through the omron sensor. I'd like to give it a go with using a relay and optoisolator as you suggested.
Also, thank you for not being rude. I bought a Rpi a day before I posted this. I don't have any prior knowledge of electronics or programming, my work is related to organic chemistry and a bit of process engineering which doesn't help with this. I spend my home time working on it. We don't have an engineer that can sort this out right now so I'm on my own. If you feel I'm asking too much, you don't need to reply.
Thank you heaps again for the information you've provided me with already.