Industrial Automation, PLC, VFD, and Troubleshooting
PLC Communication Basics
Modern PLC systems rarely work alone.
A PLC may communicate with:
HMI panels
VFDs
Remote I/O
Servo drives
Robots
Barcode readers
Vision systems
SCADA computers
Industrial switches
Other PLCs
Data collection systems
In older systems, many signals were hardwired point-to-point.
Example:
PLC output …
Read MoreIn industrial automation, a PLC program is not just a file.
It is the brain of the machine.
If the PLC program is lost, outdated, modified incorrectly, or not documented, troubleshooting becomes …
Read MoreA PLC system can run for years with very few problems, but that does not mean it should be ignored.
A PLC panel needs preventive maintenance just like motors, gearboxes, sensors, …
Read MorePLC Safety Basics
In industrial automation, safety is not just another PLC input.
Safety devices are used to protect people from hazardous machine motion, stored energy, electrical hazards, pneumatic movement, hydraulic force, …
Read MoreOpening an unfamiliar PLC program can feel overwhelming.
You may see:
Dozens of routines
Hundreds or thousands of tags
Timers and counters everywhere
Interlocks
Permissives
Fault logic
HMI commands
VFD control
Analog signals
Communication logic
Old logic that nobody remembers
Comments that may …
Read MoreCommissioning is the stage where a PLC control system moves from programmed to proven in the real machine.
A program may look correct offline and still fail during startup because commissioning …
Read MoreThroughout this PLC series, we repeatedly used an important programming concept:
Do not build your entire machine logic directly from physical I/O addresses.
Instead, create a clean separation between the real hardware …
Read MoreIntroduction
Once you understand what the FANUC Teach Pendant is, the next step is learning how to navigate the most important screens.
For an automation technician, the goal is not to memorize …
Read MoreIntroduction
Directional control valves are among the most important components in an industrial pneumatic system.
The compressed-air supply provides energy, but the directional valve determines where that air goes.
By changing the airflow …
Read More
33. PLC Programming Best Practices: Structure, Tags, Comments, and Troubleshooting ( 33 of 35 )
PLC Programming Best Practices
A PLC program should not only make the machine run.
A good PLC program should also be:
Easy to understand
Read MoreEasy to troubleshoot
Easy to modify
Easy to document
Easy to recover
Safe to …