How can I communicate between a Siemens S7-1200 and python?

python plc siemens s7-1200
Megimoo picture Megimoo · Apr 27, 2012 · Viewed 32.9k times · Source

I am running a process on a S7-1200 plc and I need it to send a start signal to my python script, after the script is done running it needs to send something back to the plc to initiate the next phase. Oh, and it has to be done in ladder.

Is there a quick and dirty way to send things over profibus or am I better off using just a RS232 thing?

Answer

Megimoo picture Megimoo · May 28, 2012

After failing with libnodave and OPC, I created a TCON,TSEND and TRECV communication thing. It transmits a byte over TCP and it works.

Related questions

How to write to PLC input registers using pymodbus

I want to write to PLC input registers using pymodbus. I am able to read them : from pymodbus.client.sync import ModbusTcpClient client = ModbusTcpClient('10.10.10.32') client.connect() reg = client.read_input_registers(1,5) print(reg.registers) But I still did …

Read More
can python software take place of logic ladder program in PLC through modbus?

Trying to figure out the best way of controlling industrial PLC's with Raspberry Pi/linux server - specifically using python and pymodbus (modbusTCP) over ethernet... Once the PLC internal registry is mapped properly to modbus, can software written in python …

Read More
Pymodbus Read/Write Floats (REAL)

I have modbus mapping setup in my AB Micro820 PLC. I have an array in 40001 for writing, and one in 42001 for reading. Both are 200 elements and REAL type (32-bit float). I can write and read currently, so I know the …

Read More