Industrial Automation, PLC, VFD, and Troubleshooting
In the previous articles, we explored several ways to organize and transfer PLC data:
Direct I/O
Alias Tags
Individual Mapping
MOV
COP
CPS
UDT-Based Architecture
Now we can bring those concepts together and build a complete digital I/O …
Read MoreIn the previous articles, we built an I/O architecture using:
Direct physical I/O
Alias Tags
Individual mapped tags
XIC/XIO and OTE
MOV
COP
CPS
These methods allow us to separate physical hardware from application logic.
But as the machine …
Read MoreIn the previous article, we built an I/O mapping layer using individual instructions.
For digital signals, we used logic such as:
XIC Physic
al_Input
OTE Internal_Tag
For numeric values, we introduced:
MOV Source Destination
This approach is …
Read MoreIn the previous article, we compared three common ways of representing PLC I/O:
Direct physical I/O
Alias Tags
Mapped controller tags
Now it is time to build the mapping layer itself.
For digital signals, one …
Read MoreIn the first article of this series, we introduced the idea of separating physical PLC I/O from application logic.
Now we can address one of the most common questions in Allen-Bradley …
Read MoreWhen working with Allen-Bradley ControlLogix or CompactLogix systems, one of the first architectural decisions a programmer eventually faces is how to handle physical I/O inside the PLC program.
At the beginning, …
Read MoreWhen programmers begin learning state machines, two names appear very quickly:
Moore Machine
Mealy Machine
Both are finite state machine models, but they differ in one very important way:
A Moore machine determines outputs …
Read MoreState machines are one of the most powerful programming concepts used in industrial automation.
They are especially useful when a machine can exist in several clearly defined operating conditions such as:
Idle
Starting
Running
Stopping
Opening
Closing
Manual
Automatic
Faulted
Instead …
Read MoreAs Studio 5000 projects become larger, tag organization becomes increasingly important.
A small machine may only have a few motors, valves, sensors, and alarms. In that type of project, individual tags …
Read MoreOne of the biggest challenges in industrial troubleshooting is dealing with problems that happen too fast to observe.
A sensor may turn off for only 100 milliseconds. A motor feedback signal …
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