Capacitive Pushbutton Sensor Switch /Indicator

We will now look at the capacitive pushbutton sensor switch and indicator. Normal pushbuttons on a panel are usually a mechanical device. They can become “sticky” when too much dirt or oil is present. Capacitive push buttons do not have moving parts to stick, so the life expectancy is increased. Disinfectant sprays can be applied … Read more

Stop Wiring DC Sensors Wrong: NPN vs PNP Made Simple

Wiring 3 wire DC sensors can be confusing. I recently received a question on PNP and NPN sensors. They wanted an explanation of what a sink is and how to wire one. Confusion over the Normally Open and Normally Closed function of the sensor is also a common question. Several diagrams will show a resistor … Read more

Why Ultrasonic Sensors Outlast Every Other Switch on Your PLC

An ultrasonic sensor (switch) is able to detect object presence without physical contact (limit switch). No physical contact means that the switch has no parts that will wear out. The life span of the sensor is increased with less maintenance. An ultrasonic sensor will use sound waves to detect objects. These sound waves are at … Read more

Wiring an NPN PNP Sensor to the Click PLC

A proximity sensor (switch) is able to detect object presence without physical contact like a limit switch. No physical contact means that the switch has no parts that will wear out. The life span of the sensor is increased with less maintenance. A capacitive proximity sensor will detect ferrous and non-ferrous objects. The sensor works … Read more

Wiring an Inductive NPN PNP Sensor – Click PLC

We will now look at wiring an NPN and PNP inductive proximity sensor to the Click PLC. A proximity sensor (switch) is able to detect object presence without physical contact like a limit switch. No physical contact means that the switch has no parts that will wear out. The life span of the sensor is … Read more

Click PLC Wiring Secrets: Push Button & Switch Connection

We will now look at wiring a click plc with selector switch and pushbuttons. A push button (pushbutton) is a simple human interface for controlling some aspect of a machine or process. The push button requires a force to push the button to change the electrical operation from off to on or vice versa. The … Read more

Why Mixing NPN & PNP Sensors Will Destroy Your PLC

Wiring Interposing Relays - NPN PNP Isolation

We will now look at wiring interposing relays to connect an NPN and PNP sensors into the PLC. Interposing relay means a device that will separate two different circuits. The isolation can be for current consumption, voltage differences, voltage references, or a combination of both current and voltage. We can use these relays to help … Read more

Master PNP & NPN Sensor Wiring: Pro PLC Connection Secrets!

Here’s a Quick Way to Wire NPN and PNP devices I often get asked how to wire NPN and PNP devices to the programmable logic controller. This can be unclear at first when looking at the wiring diagrams. I have managed to destroy a few sensors in the process….. so let’s get started, and I … Read more