Latest PLCs & PACs Technical Articles

Linear position sensors are used in electrical and fluid-actuated motion devices. They allow extremely precise position,…

Linear position sensors are used in electrical and fluid-actuated motion devices. They allow extremely precise position, velocity, and acceleration control, and provide feedback to ensure product quality and tolerance compliance.

Before digital control systems, responses were fairly slow. Push a button, and a motor contactor engaged. These days, the…

Before digital control systems, responses were fairly slow. Push a button, and a motor contactor engaged. These days, the speed of computers introduces some new challenges but brings solutions as well.

Modbus is a communication protocol stemming from the early days of Modicon PLCs, but is still common today. These two…

Modbus is a communication protocol stemming from the early days of Modicon PLCs, but is still common today. These two example implementations of Modbus transactions will get you started.

Inductive loads, such as solenoids and contactors, can cause arcs and failures back into electromechanical switching…

Inductive loads, such as solenoids and contactors, can cause arcs and failures back into electromechanical switching devices, causing costly downtime. The solution is cheaper than you think.

Failures of I/O systems are a common source of headache for control engineers. Troubleshooting those devices that have…

Failures of I/O systems are a common source of headache for control engineers. Troubleshooting those devices that have polarized connections (source vs sink, and NPN vs PNP) is a technique worth refining.

Power delivered to devices can be changed by raising or lowering the voltage and current. But this method does not always…

Power delivered to devices can be changed by raising or lowering the voltage and current. But this method does not always produce intended results. Pulse width modulation (or PWM) can be used to better control variable loads.

What is a PLC? This article will lay out a succinct definition of a programmable logic controller and explain its basic…

What is a PLC? This article will lay out a succinct definition of a programmable logic controller and explain its basic components.

In the late 1960s, a revolution in manufacturing became a reality when the first Programmable Logic Controller (PLC) was…

In the late 1960s, a revolution in manufacturing became a reality when the first Programmable Logic Controller (PLC) was developed. We’ll examine the early history of the PLC - not just the technology, but also the inspiration of the inventors as well.

We’re all familiar with information technology, or IT. The computer systems, hardware, internet, and various software…

We’re all familiar with information technology, or IT. The computer systems, hardware, internet, and various software we use in our own homes and offices are mostly IT. But when it comes to industrial workplaces, the rules are different.

Digital control systems are particular about the direction of current flow from sensors and input devices. The terms…

Digital control systems are particular about the direction of current flow from sensors and input devices. The terms sourcing and sinking (often abbreviated source and sink) are among the more confusing ratings found on I/O module datasheets. Part 1 of a 3-part series.

Any industrial electrician can instantly recognize a relay, but when it comes to wiring, why are the terminals numbered…

Any industrial electrician can instantly recognize a relay, but when it comes to wiring, why are the terminals numbered in such apparently random order?

In this article, learn the basics of Allen-Bradley Data Highway, the various network structures, and the relationship…

In this article, learn the basics of Allen-Bradley Data Highway, the various network structures, and the relationship between DH and Ethernet networks.

One of the most visible elements of industrial safety is the use of lock-out-tag-out (LOTO) devices, familiar to those…

One of the most visible elements of industrial safety is the use of lock-out-tag-out (LOTO) devices, familiar to those with experience. But, if you are new to the workforce, a brief introduction may be helpful.

What is laser sensing, how does it work, and what types of laser sensors exist?

What is laser sensing, how does it work, and what types of laser sensors exist?

This article teaches the basics of gateways in industrial networks and PLC-to-PLC communication.

This article teaches the basics of gateways in industrial networks and PLC-to-PLC communication.

Learn the basics of connecting multiple PLCs to an HMI using various data types.

Learn the basics of connecting multiple PLCs to an HMI using various data types.

Noise signal sources occur primarily from radiofrequency interference (RFI), often in the form of impulse functions or…

Noise signal sources occur primarily from radiofrequency interference (RFI), often in the form of impulse functions or arcing. How do you mitigate process noise from your control system?

Ladder diagrams, or ladder logic, is a popular programming language used for PLCs. Programmers can utilize boolean logic…

Ladder diagrams, or ladder logic, is a popular programming language used for PLCs. Programmers can utilize boolean logic as a base for their ladder diagrams. Learn the basics and structures for boolean logic.

AVEVA Solutions, formerly Wonderware, is a popular service that offers HMI, SCADA, and MES. How is each solution used in…

AVEVA Solutions, formerly Wonderware, is a popular service that offers HMI, SCADA, and MES. How is each solution used in industrial automation?