We want to read data from a Siemens S7-1200 into an industrial PC for logging and display. Which route should we take?

Three common routes; pick by the software you already run: 1. OPC UA. Recent S7-1200 firmware includes an OPC UA server (it must be enabled, and some CPU versions need a licence). This is the cleanest path: an open standard with encryption and authentication that most SCADA/MES software reads directly. 2. S7 communication over PROFINET/TCP, using a library that reads DB memory areas directly. Fast and licence-free, but you manage memory addressing yourself and must allow access in TIA Portal (clear the PUT/GET restriction for this method). 3. Modbus TCP via an expansion module, if your system already speaks Modbus. Hardware: use a machine with at least two LAN ports — one for the control network, one for the office network — and do not share a switch with printers or guest Wi-Fi. Assign static IPs to both PLC and PC and document the address plan. Data: sample only as fast as you need (200 ms–1 s is typical for monitoring), write to an industrial SSD, and keep the data partition separate from the OS partition.