PLC Discrete Inputs - Control Automation

Programmable logic controllers (#PLCs) receive vital information about the #manufacturing process and use that data to generate logical output signals to the final control elements. Obtaining the information from buttons, switches, and sensors is naturally the first step in this control system process. Connecting buttons and switches allow the human operators to perform some basic controls like starting or stopping a motor, setting a machine into manual or automatic control, or activating a new process or batch of materials for manufacturing. #sensors are broken into two categories: discrete (on/off), or analog (variable) signals. The discrete sensors can be either AC or DC, but the connection method remains the same. They may have 2 or 3 wires, but once again, the completion of a circuit is the single objective of connecting inputs to a controller. Using this unified perspective of all kinds of devices, we explain the wiring process on several different PLCs. Although the purpose of controller wiring remains the same across various types of inputs, there are certainly subtle differences. To explain the difference between ‘source’ and ‘sink’ wiring and between ‘PNP’ and ‘NPN’ devices, we created a Control.com exclusive eBook that we encourage you to download for free. (control.com/industry-white-papers/control-ebook-th…) We explore three different manufacturers: ‪@RockwellautomationInc‬ (CompactLogix), ‪@SiemensKnowledgeHub‬ (S7-1200), and ‪@automationdirect‬ (Productivity 1000). If you have an additional product that you would like to see featured, please reach out to our team, and be sure to follow the other educational content on Control.com. Technical Articles: control.com/technical-articles/ News Articles: control.com/news/ Textbook: control.com/textbook/ Webinars: control.com/industry-webinars/ And be sure to follow Control Automation on social media. Facebook: www.facebook.com/CtrlAutomation LinkedIn: www.linkedin.com/company/control-com/ Twitter: twitter.com/ctrlautomation