Practical Tips and Techniques
To ensure the proper functioning of any PLC digital input, it is crucial to correctly test and wire the discrete inputs. By understanding the testing process and providing accurate wiring, we can guarantee the optimal performance of our PLC hardware. Testing the inputs allows us to verify that they function as intended and that our … Read more
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
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
Signal conditioners are used with analog current and voltage signals. They have the ability to change your input analog signal to another output analog signal. As an example, we can have 4-20mA analog input and change it to a 0-10VDC output signal so we can wire this into our PLC. Typically signal conditioners will also … Read more
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
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