Two Zones That Disagree About Who Owns the Box: The Handshake That Restarts a Stuck Conveyor
Why an accumulation zone stops with nothing on it: how the zone ownership handshake half-completes, the one-state fix, and the run that restarts it.
First Scan Bit
Common PLC Programming Mistakes: Six That Cost Hours
Six common PLC programming mistakes, each with the symptom at the panel and the Rockwell publication that explains it, from stop wiring to task overlap.
PLC Scan Time and Cycle Time: Measure It, Then Cut It
Read real scan times with GSV on a ControlLogix and the cycle time view on an S7-1500, then find what is eating them before the watchdog does.
Studio 5000 Watch Window: Monitor Tags While Online
Build watch lists in the Studio 5000 Watch window, monitor and write tag values online, and know when the sample rate hides what you are chasing.
PLC Water Treatment: Levels, Lead/Lag Pumps and Dosing
Wet well level control, pump alternation that shares the wear, chlorine dosing with long dead time, and remote sites over cellular Modbus that go quiet.
PLC Sequencer Instructions: SQO, SQI and the Position 0 Trap
PLC sequencer programming with SQO and SQI, why position zero never fires on the first transition, and how to drive a rotary indexer from it.
PLC First Scan Bit
What the PLC first scan bit S:FC does when the controller goes to run, and where it earns its place: power-on timers, resets, sequencer defaults.
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