19. PLC Forcing: When to Use It and When Not To


0

In 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 …

Read More

18. Program Control Instructions: JSR, MCR, JMP, and Fault Routine


0

In PLC programming, not every instruction directly turns on a motor, counts a box, or starts a timer.

Some instructions are used to control how the PLC program executes.

These are called …

Read More

17. High-Speed Counters and Encoders


0

In the previous post, we covered standard PLC counters such as:

CTU = Count Up
CTD = Count Down
CTUD = Count Up / Count Down

Those counters work well for many basic counting …

Read More

16. PLC Counters: CTU, CTD, and One-Shots


0

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 …

Read More

15. Cascading Timers and Practical Timer Applications


0

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 More

14. Timers in PLC Programming: TON, TOF, and RTO


0

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 More

13. Electrical Interlocking in PLC Programs


0

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 More

12. Seal-In Circuits Explained


0

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 More

11. Basics of Ladder Logic Programming


0

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 More

10. Fundamentals of Logic: AND, OR, NOT in Ladder Logic10.


0

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 More