Articles - PLC Programming & Automation

EtherCAT PLC Systems: Cycle Time and Distributed Clocks

September 12, 2026January 17, 2024 by PLC

Timing chart of a 1 ms EtherCAT cycle showing the task window, the frame on the wire, and the SYNC0 pulse that applies outputs on every slave at the same instant

Set up an EtherCAT bus in TwinCAT 3: ESI files, scanning the line, picking a cycle time, distributed clocks and the CRC counters that find a bad cable.

PLC Programming for Beginners: Your First Working Project

September 13, 2026January 8, 1970 by PLC

Ladder rung with Start in parallel with the Conveyor seal-in contact, in series with a normally closed Stop contact and a normally closed Overload contact, driving the Conveyor output coil

PLC programming for beginners without the theory dump: pick a simulator, write a start/stop rung, add a timer and a counter, wire one HMI button.

PLC Hardware Components and the Software That Uses Them

September 13, 2026January 6, 1970 by PLC

Timing chart showing a field input rising, the input image bit following at the next input scan, the coil in logic changing during the program scan, and the physical output finally switching after the output scan, about one scan behind the field

What is in a PLC rack and how the software sees it: power supply budget, CPU memory, I/O cards, tasks and routines, and tags against S7 addresses.

Wireless PLC Communication: Wi-Fi, Radios and Cellular

September 13, 2026January 4, 1970 by PLC

Timing chart of a wireless link: the radio link drops, I/O data stops arriving, the connection fault bit sets after the timeout window expires, the line stops, and everything recovers only after the link returns and the logic is reset

Wireless PLC communication done properly: choosing Wi-Fi, 900 MHz radios or cellular, RPI and timeout budgets, antennas, roaming, and link loss logic.

Functional Safety PLC: Risk Assessment to PLd Architecture

September 13, 2026January 3, 1970 by PLC

Timing chart of a guard door safety function: the door opens, the safety function result drops shortly after, the contactors release inside the response time budget, and the output only returns after a manual reset pulse with the door closed

How functional safety works on a PLC job: the ISO 13849-1 risk graph, PLr, category 3 architecture, MTTFd, DC, CCF, a PFHd budget and SISTEMA.