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Click Click PLUS Communication Modbus RTU Modbus TCP PLC PLC Learning WiFi

Click to Click PLC Communication – Remote IO

We will connect two Click PLUS PLCs and communicate in three different ways. Using the send and receive commands, we will set up one PLC to be the master (client) and communicate with the slave (server). WiFi, Ethernet, and Serial communication will share common memory areas between the Click PLCs.
Click to Click PLC CommunicationThe send and receive commands have been covered before in our Click PLC Series, but we will look further at the timing of the communication. Detecting and correcting communication errors will be discussed and implemented. We will also create a heartbeat for the remote Click slave (server) PLC. This will allow the remote controller to determine if communications have stopped with the Click master (client). Wiring a pushbutton and some ladder logic code will allow us to time the throughput of each of the communication methods. Let’s get started.

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BRX Do-More Do-More Inputs PLC PLC Basics PLC Learning Scan

BRX Do-More PLC High-Speed Input Pulse Catch

The High-Speed Input Pulse Catch will set an output that can be seen by the PLC ladder logic scan in response to an input pulse. Inputs that are too fast to reliably be seen by the ladder logic scan time will be seen.
BRX Do-More PLC High-Speed Input Pulse CatchThe BRX Do-More series of programmable logic controllers have built-in high-speed inputs. These inputs can function in Counter, Timer, or Pulse Catch modes. Every CPU will have either 6 or 10 high-speed inputs (HSI) available depending on the model. These inputs can be used for input frequencies from 0 to 250Khz. 250Khz represents 250000 input counts per second that can be coming from devices connected to your PLC like an encoder. Due to the speed of the inputs, they function on the BRX Do-More PLC asynchronous with the PLC scan time.
We will continue looking at the high-speed inputs on our BRX Do-More PLC, by looking at the pulse catch mode. The pulse catch mode will be set up using the Z phase of our incremental encoder. Pulses will be counted using the input directly in the ladder logic and using the pulse catch bit. Comparisons will be made between the two counts and an output will be turned on when different. Let’s get started.

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Click Click PLUS Communication EasyPLC Machine Simulator Inputs Modbus RTU Modbus TCP Outputs PLC PLC Basics PLC Learning

Click PLC – Easy Transfer Line Programming

EasyPLC Software Suite is a complete PLC, HMI, and Machine Simulator Software package. This PLC learning package includes a Machine Simulator (MS). This virtual 3D world with real-time graphics and physical properties can communicate to several different programmable logic controllers. (PLC)
Click PLC – Easy Transfer Line ProgrammingWe will be developing a Click PLC program for a transfer line. This is just one of the prebuilt machines in the simulator to learn PLC programming. We will be developing the ladder logic, connecting via Modbus RTU, and testing our program. This will be done using the five steps to PLC program development. Let’s get started!

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Click Click PLUS Communication Modbus RTU Modbus RTU PLC PLC Learning Solo Process Temperature Controller

Click PLC Serial Communication Timing

Many questions come from serial communications using the Click PLC. Most of these questions deal with communication timing when using multiple send and receive instructions. We will show you how to deal with serial communication timing in the Click PLC.
Receive and Send instructions will allow you to send and receive serial data to an external device. The communication method that you set up can be ASCII or Modbus. ASCII (American Standard Communication for Information Interchange) can be used to send to devices such as a printer. Receiving ASCII can be used for connecting barcode scanners to the PLC. The barcode will be read as an ASCII string in the PLC. Modbus serial communication (Modbus RTU) is a standard protocol used in many automation devices.
Click PLC Serial Communication Timing
We will demonstrate the Send and Receive instruction by communicating Modbus RTU to a Solo Temperature Controller. Parameters from the Solo process temperature controller will be read using multiple receive instructions. The send instruction will be used multiple times as well to set the Set Value (SV) and Limits of the SV value entered in the temperature controller. The set values will only be changed when required. Let’s get started.

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Click PLUS PLC PLC Learning Timers

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 that we can turn on and off based on the time change in the area.
Click Plus Real Time Clock Setup and Use
We will be setting up the network time service on our Click Plus. The real-time clock (RTC) will be updated via the internet time service. Daylight savings time and the RTC will also be programmed. This will be based on our previous Click Real-Time Clock post. Let’s get started.

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Click PLUS Communication MQTT Node-RED PLC

Click Plus PLC MQTT Communication

We will now look at the MQTT communication capability using our Click plus PLC.
MQTT stands for Message Queuing Telemetry Transport. This simple ‘publish and subscribe’ communication protocol, does not take too many resources.
Constrained devices with low bandwidth are ideal for MQTT. This protocol provides machine-to-machine (M2M) connectivity which is ideal for the Internet of Things. (IoT) This protocol is not for remote IO or real-time (deterministic) applications. MQTT is a good solution for applications that move data from hundreds or thousands of machines (sensors) to clients in many networks.
Click Plus PLC MQTT Communication
We will be installing a windows based broker called Mosquitto. The Click Plus PLC will be one of the clients publishing and subscribing to the MQTT broker. Node-RED will be the other client publishing and subscribing to the MQTT broker. Each client will share information. Let’s get started.