Industrial automation project
I have an opportunity to improve a current installation in a factory. We have 14 vacuum pumps that run all day. Each of some CNC machines use the pumps to operate vacuum beds to hold the workpieces.
I would like to join the pumps together to a manifold, and then use a Pi to monitor the vacuum level required in real time, and turn on and off more or less pumps as the vacuum demand grows or shrinks.
If this goes ahead, I'll keep this thread updated with my progress. I am interested to know if anyone else has used a Unipi in a large industrial setting?
depends on what "large" means for you. If 10=large then we did: http://unipi.technology/customer-reference-unipi-likes-rex-controls/
Your project is very nice, looking forward to hearing more about it!
I have a design requirement to my project as follows:
I will be reading at least 5 seperate vacuum meters which give analog signals (either 0-10v or 0-5v). Depending on the readings in real time, I can see where there may be a vacuum "leak", and turn off the valve to that part of the system, or see where there is a demand and start turning on pumps.
I have been looking at ways to read this many analog inputs, but without a solid solution.
But when I thought about it, I can change my design from having one unipi reading all the inputs, making all the decisions and controlling all the valves to a more distributed system. What if I used 1 Unipi to monitor 1 vacuum meter, and control just the valves that relate to that part of the manifold, and called this a "Local Control Unit". I could then create 5 separate "Local Control Units" and each of them doing the exact same thing, but locally. I could then have 1 more Unipi that is the "Master Control Unit" that would just monitor the other Unipi's, and in my software it could issue override commands to any local device to turn on or off valves if required (Maintenance or whatever).
This means buying a lot more hardware, but it's a very solid basis, and makes the software on each machine simpler.
Any thoughts from anyone on this?
For sure this is possible, it is called a distributed control system. The software will be more complex (e.g. you must handle network communication problems correctly) but you will not have a single point of failure. When the Local Control Unit looses connection with the Master Control Unit, it will still work locally, you can even define an emergency or fail-safe mode.
The master control unit needs no I/O, it can be a plain Raspberry Pi. Or you can use 1 master/local unit and 4 local units.
For communication, I would use Modbus TCP.
I've ordered a S103 to get me started and see how I get on at the software. I plan to write this in Python, and I see there are Libraries for Modbus available.
I'm sure I'll be back with more thoughts and experiences as this project progresses.
Sure there is a solution for each industrial. We hope this is a challenging work to bring the automation in this industry.