7. PLC Addressing: Rack/Slot vs Tag-Based ( 7 of 35 )
PLC Addressing: Rack/Slot vs Tag-Based
In a PLC system, every input, output, and internal memory location needs a way to be identified by the controller.
This identification method is called addressing.
In simple …
Read More8. PLC Memory Basics: Bits, Words, DINTs, and Tags ( 8 of 35 )
To understand PLC programming, you need to understand how a PLC stores information.
A PLC does not only turn inputs and outputs ON or OFF. It also stores data in memory.
That …
Read More10. Fundamentals of Logic: AND, OR, NOT in Ladder Logic. ( 10 of 35 )
Before 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 More11. Basics of Ladder Logic Programming (11 of 35 )
Ladder 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 More12. Seal-In Circuits Explained ( 12 of 35 )
Seal-In Circuits Explained
A seal-in circuit is one of the most important basic patterns in PLC ladder logic and relay logic.
It is commonly used when an operator presses a momentary Start …
Read More13. Electrical Interlocking in PLC Programs ( 13 of 35 )
An 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 More14. Timers in PLC Programming: TON, TOF, and RTO ( 14 of 35 )
Timers are one of the most common instructions used in PLC programming.
A timer allows the PLC to use time as part of the control logic.
In simple words:
A PLC timer waits …
Read More15. Cascading Timers and Practical Timer Applications ( 15 of 35 )
In the previous post, we covered the basic PLC timer instructions:
TON = Timer On Delay
TOF = Timer Off Delay
RTO = Retentive Timer On
Now we are going one step deeper.
In real …
Read More16. PLC Counters: CTU, CTD, and One-Shots ( 16 of 35 )
In industrial automation, PLC counters are used when a machine needs to count events.
A counter can count:
Parts
Boxes
Bottles
Cycles
Machine strokes
Rejects
Pallets
Sensor pulses
Production totals
A counter does not count time.A counter counts how many times …
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