In industrial automation, the words permissive and interlock are often used as if they mean the same thing.
They do not.
Both are conditions that influence whether equipment is allowed to operate, …
Read MoreIntroduction
One of the best ways to improve PLC programming skills is to stop thinking only in terms of individual instructions and start thinking in terms of process behavior, equipment states, …
Read MoreA PLC programmer does not need to be a chemical engineer, mechanical engineer, process engineer, electrician, instrumentation specialist, and machine designer all at the same time.
But there is another extreme …
Read MoreOne of the most useful PLC programming patterns a technician can learn is also one of the simplest:
Trigger → Hold-In → Interrupt
The idea is straightforward.
Something starts the action.
Something keeps it …
Read MoreThroughout this series, we have explored several different ways to handle I/O in Studio 5000.
We started with the simplest possible approach:
Local:1:I.Data.0
Then we introduced:
Alias Tags
Individual Mapping
MOV
COP
CPS
UDTs
Digital I/O Processing
Analog Scaling
Analog Output Processing
Performance …
When 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 MoreBefore learning advanced PLC programming, every automation technician must understand the basic logic operations used in ladder logic.
The three most important logic functions are:
AND
OR
NOT
These are the foundation of almost every …
Read MoreLadder Logic is one of the most common PLC programming languages used in industrial automation.
It was designed to look similar to electrical relay control circuits, which makes it easier for …
Read MoreAn interlock is a condition used to prevent two incompatible or unsafe actions from happening at the same time.
In simple words:
An interlock blocks an action when another condition makes that …
Read MoreIn PLC troubleshooting, one of the most powerful and dangerous tools is forcing.
A PLC force allows a technician or programmer to manually override the normal state of an input or …
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