I am working on a simple dashboard in Ignition Perspective to track lot progress in a few workstations in our clean environment.
I am looking for a cheap and effective way to count the number of cycles on a machine and see this count as a Tag in Ignition Edge. Something like a proximity sensor or a mechanical limit switch that gets triggered every time a machine cycle occurs. This could also be a device with just a single DC input that reads an output from a machine and looks for a rising edge, etc.. Honestly, the second option would be preferable.
This device would need to connect to the same network as my Ignition Edge gateway, either wirelessly or via ethernet.
Ideally I would connect these machines to the gateway directly instead of using an external device to monitor them, but they are old and not compatible, and I don't see us moving away from them anytime soon.
Has anyone done something similar?
I will also add that this counter is intended to track progress in an individual lot and I will want this value to reset each lot, so I don't want a counter that needs to be manually reset.
If you don't mind taping a small PLC onto the side of said machines, the Click PLCs from Automation direct excel at this. Low cost with a small amount of embedded I/O (expansion modules are also available). They are modbus TCP capable, so you will be able to connect them to Ignition with minimal issue.
Have this PLC store a never resetting counter value (odometer style). Increment the counter per cycle, and store the value of this counter at a set rate into your db.
Log the value of the counter whenever the lot number changes. Maybe have the PLC monitor the lot number and store the lot number, odometer value, and timestamp in a small FIFO array on value change. Read from this array and insert any missing records into another DB table to keep track of lot changes.
From this, you can use lead/lag in a query to get total cycles between two points in time, and also break it down to cycles per lot in that time period.
3 Likes