PLC - PLC Programming & Automation

RFID PLC Integration: Read and Write Tags from Ladder

Timing chart of an RFID read cycle: the trigger bit, the reader busy bit, the done bit, and the UID landing in the UDT before the trigger is cleared

Pick HF or UHF, connect the reader over EtherNet/IP or Modbus, map the data into a UDT, and run a trigger, busy, done handshake that does not drop reads.

PLC Safety Interlock: Dual-Channel E-Stop on GuardLogix

by PLC

Timing chart of a dual channel E-stop: channel A opens, channel B follows shortly after inside the discrepancy time, the safety output drops at once, the E-stop is released, and the output only returns after the reset button is pressed and released

When a standard interlock is not enough, how to wire and configure a dual-channel E-stop on GuardLogix safety I/O, and the reset rule nobody may break.

PLC Lean Manufacturing Data: OEE, Downtime Codes and SPC from the Controller

by PLC

Ladder rung with four contacts, Auto examined on, Fault, Starved and Blocked examined off, driving the Running output coil that feeds the availability run timer

How a PLC state model feeds OEE, downtime reason codes and SPC triggers on a rotary filler: the ST block, the tag structure and the classic mistakes.

PLC Simulation and Virtual Commissioning: A Working Setup

by PLC

Timing chart of a simulated conveyor: the run command, the simulated photoeye going true three seconds later, and the drive feedback reaching the speed reference

Build a Logix Emulate chassis, run PLCSIM Advanced, test the HMI offline, and learn which parts of a machine you can trust a simulation to prove.

PLC Chemical Process Control: BPCS, SIS and Interlocks

by PLC

Timing chart of a reactor high temperature trip: two of three jacket thermocouples vote high, the SIS trip relay trips, the feed valve closes and the quench valve opens

How the BPCS, the SIS and the package PLC split the work on a batch reactor, with a cause and effect matrix, cascade temperature control and IS barriers.

PLC Oil and Gas: Wellhead RTUs, ESD Logic, Tank Farms

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Ladder rung for a wellhead ESD permissive: reset push button sealed in, high pressure and high level switches healthy, emergency stop normally closed, driving the SDV permissive coil

Wellpad controller choice, an ESD permissive rung that will not auto restart, Modbus poll budgets over radio, flow computers and tank farm level control.

How to Create a Project in Studio 5000 (Step by Step, v33)

by PLC

Start/stop rung with seal-in: XIC Start in parallel with XIC Motor, XIO Stop, OTE Motor

Create a new Studio 5000 Logix Designer project the right way: pick the controller, match the firmware revision, add I/O, write the first rung, download and go online.

PLC Automotive Manufacturing: Station and Line Logic

by PLC

Ladder rung releasing a body from an assembly station: body present, torque batch complete and vision result OK in series, with a normally closed contact for the downstream station blocked, driving the release output

Station and line PLC split, a PackML state machine in Structured Text, torque tool error proofing, andon stops and downtime that blames the right station.