The 7 Essential Parts of a PLC System

We will now look at the parts of a PLC system. When I was in school PLCs were just in their infancy. We were taught that the PLC consisted of the central processing unit (CPU), analog and digital inputs, and outputs. Everything was programmed with dedicated handheld devices and/or software devices on specialized hardware. We … Read more

Understanding the PLC Program Scan

Understanding how the PLC will scan and update your program is critical in programming and troubleshooting your system. Typically a PLC will solve your logic from left to right, top to bottom. The status of the memory from the previous rung, are available for the next rung to use. We will look at a few … Read more

PLC Programming – Delay Starting of 7 Motors

PLC Programming Example – Delay Starting of 7 Motors

We will look at a PLC programming example of delaying the start of 7 motors. Each motor will be on a switch that the operator can select at any time. The motor outputs should have a 5-second delay between the outputs coming on. This question originally came from PLCTalk.net. An original solution to the problem … Read more

Click PLC Timers and Counters Programming

Continuing our series, we will now look at timers and counters and how they are used in the Click PLC. Previously we have discussed: System Hardware – Video Installing the Software – Video Establish Communication – Video Numbering System and Addressing – Video The programming software and manuals can be downloaded from the Automation Direct website … Read more

Modbus TCP Data Logging to Database

Using Visual Basic 2015 we will log three holding registers from the PLC along with time and date into a Microsoft Access Database. We will log every minute into the database with the information that we collect from the PLC via Modbus TCP (Ethernet). All code will be done and shown so you can implement this in … Read more