Raspberry Pi Serial Port Programming

Raspberry Pi Serial Port Programming

Node-RED will be used on the Raspberry Pi 4 to communicate serial Modbus RTU to a Solo process temperature controller and Click PLC using twisted pair RS485. This will be done on the same serial network so the devices will be daisy-chained together on the two wires. We will be reading the PV (present value) … Read more

Node-RED Modbus TCP Handling Errors

Node-RED Modbus TCP Handling Communication Errors

Node-RED Modbus TCP can recover from communication errors automatically. Options are available to you the programmer to continue the Node-RED flow upon detection of these errors. Broken Ethernet cable, Modbus Server power, and Node-RED Client offline are just a few of the errors that can occur on the industrial plant floor. Our Node-RED program must … Read more

Simple Click Data Logging – Node-RED

Simple Click Data Logging

We will now be looking at simple data logging using a Click PLC with an Ethernet port. Node-RED will be used to communicate to the controller via Modbus TCP protocol. Information collected will be then stored in an SQLite SQL database. A Raspberry Pi 4 single-board computer will be used for the Node-RED collecting and … Read more

Click Plus Real Time Clock Setup and Use

Click Plus Real Time Clock Setup and Use

The real-time clock on the Click Plus can now be more accurate. A network time service (NTP or SNTP) has been added to the Click Plus controller. This will allow the time to be synchronized with an internet time server or local network. Daylight savings time is quickly implemented with just a memory retentive bit … Read more

Do-More PLC Node-RED HTTP Request

Do-More PLC Node-RED HTTP Request

Node-RED HTTP Request can be used to read any BRX Do-More PLC memory area. This HTTP (Hypertext Transfer Protocol) communication will only read information from our controller. The BRX Do-More REST API is used to read information using a URL (Uniform Resource Locator) or web address. We will be using the HTTP request node in … Read more

Click Plus Data Logging – CSV File SQL Database

Click Plus Data Logging - CSV File SQL Database

We will now look at the data logging capability using our Click plus PLC. Data logging is the collection of data over time. This is usually used for data analysis at a later time. The amount of data (System Information) stored and the frequency of the storage will depend on your specific application. The hardware … Read more