PLCs and Python don’t usually hang out together. One’s rigid, real-time, industrial. The other’s flexible and everywhere. But put them together and things get interesting.
Enter pylogix โ a Python library that talks directly to Rockwell/Allen-Bradley PLCs over EtherNet/IP. No OPC server, no extra middleware. Just Python. ๐
Install it:
bash
pip install pylogix
Enter fullscreen mode Exit fullscreen mode
Read a tag:
python
from pylogix import PLC
with PLC("192.168.1.10") as comm:
r = comm.Read("Motor1_Running")
print(r.TagName, r.Value, r.Status)
Enter fullscreen mode Exit fullscreen mode
That’s it. Three lines and you’re pulling live data off a PLC. ๐ฅ
Reading a few tags at once? Just pass a list:
python
tags = ["Motor1_Running", "Motor1_Fault", "Tank1_Level"]
with PLC("192.168.1.10") as comm:
for r in comm.Read(tags):
print(r.TagName, r.Value)
Enter fullscreen mode Exit fullscreen mode
Writing? Possible, but be careful โ ๏ธ โ only write tags you fully understand, never touch safety logic.
Why bother? Because once you can read tag data in Python, you unlock stuff PLCs just aren’t built for:
๐ Real-time alerts (email, Slack, even voice)
๐ Dashboards
๐๏ธ Logging to a database for trends
โ๏ธ Cloud integration
A couple of real-talk tips:
Don’t poll every millisecond โ 1 tag read/sec is usually plenty
Handle disconnects, networks drop
Never expose your PLC to the internet ๐ซ
Python doesn’t replace the PLC. It just gives it a voice. ๐ฃ๏ธ
Have you connected Python to a PLC before?
What’d you use โ Modbus, OPC UA, pycomm3? Drop it below ๐
๋ต๊ธ ๋จ๊ธฐ๊ธฐ