The Do-More Designer Programming Software (2.9) or higher includes a Modbus I/O Scanner with some profiles for Modbus Server (Slave) devices. This will greatly reduce the time it takes to implement and troubleshoot communications in your projects. Modbus communications are done independent of the PLC scan time and will have little or no ladder logic for the program.
Last time we communicated to a Solo process temperature controller via Modbus RTU RS485. (twisted pair) We manually set the Modbus IO scanner, reading the present value (PV) and set value (SV) of the Solo. The writing of the set value (SV) located within the BRX Do-More controller was also done. This was all be done without using any ladder logic code. We will now use the Modbus profile in the Modbus IO Scanner to connect a Click Plus PLC to our RS485 network. Using the Modbus scanner to write and read instructions we will also show how to use the ladder logic code with our scanner. Let’s get started. Continue Reading!
The newest version of the Do-More Designer Programming Software (2.9) includes a Modbus I/O Scanner. This Modbus scanner will simplify Modbus RTU serial communications to any device. Communications are done independent of the PLC scan time and will have little or no ladder logic for the program.
We will be communicating to a Solo process temperature controller via Modbus RTU RS485. (twisted pair) Setting up the Modbus IO scanner and reading the present value (PV) and set value (SV) of the Solo. We will also write the set value (SV) located within the BRX Do-More controller. Communications will happen without using any ladder logic code. Let’s get started. Continue Reading!
The element browser in the Do-More Designer software will display valid memory locations, add documentation, and show how to cast from one memory type to another.
We will be discussing the element browser and how to take advantage of this in your Do-More program. Let’s get started. Continue Reading!
The BRX Do-More PLC Peerlink Ethernet communication network is one of the easiest networks to set up and run. Peerlink is a shared programmable logic controller (PLC) common memory area within a local network. Do-More central processing units (CPUs) or DirectLogic PLC systems using ECOM100 modules can read the entire area and write to their programmed area if selected.
The network uses TCP/IP broadcast packets to publish the blocks of data PEERLINK (PL) memory to all of the devices attached. This broadcast will share the data network to the local domain only. Each member can optionally send data to the other members of the data-sharing network by electing to “publish” one or more blocks of PEERLINK (PL) memory.
This can sound confusing at first, but it is the simplest network to set up. You can have your Peerlink network up and running in a matter of minutes. We will be setting up and demonstrating the Peerlink network using a BRX BX-DM1E-18ED13 and the Do-More Simulator. Let’s get started. Continue Reading!
Do-more plc modbus ascii protocol will be used to communicate to a Solo process temperature controller. A sample program will explain in detail how this is accomplished through a serial port.
Modbus is a communication method used for transmitting information over serial lines between electronic devices. The device requesting the information is called the Modbus Master (Client) and the devices supplying information are Modbus Slaves (Servers). This protocol was originally developed by Modicon systems.
Modbus protocol comes in basically three different types. Ethernet (Modbus TCP) or Serial (Modbus RTU or Modbus ASCII). Modbus TCP and Modbus RTU come as standard protocols in the BRX Do-More series of PLCs.
We will connect the BRX Do-More PLC to a Solo process temperature controller. This will be done using the Modbus ASCII protocol over serial RS485 communication wire. (Media) The present and set values (PV / SV) will be read from the Solo controller and the set value will be written when required. Let’s get started. Continue Reading!
The BRX Do-More PLC can communicate to a remote I/O (input and output) controller modules using the Modbus protocol for communications. The BX-MBIO provides both Modbus RTU and Modbus TCP interfaces. Modbus RTU is a serial communication and Modbus TCP is an Ethernet communication. Modbus RTU is supported over an RS-485 serial connection. Modbus TCP is supported over an Ethernet connection. They function as listening/replying devices (slave, server) and can connect with any mastering (master, client) device that communicates using the Modbus protocol.
Previously we looked at the BX-MBIO Modbus RTU TCP Remote IO Controller wiring and configuration.
Modbus RTU TCP Remote IO Controller BX-MBIO
– BX-MBIO Hardware Video
– BX-MBIO Powering and Configuring Video
We will connect the BRX Do-More PLC to the Modbus remote IO. This will be done using the Modbus TCP and Modbus RTU protocol. Ethernet and serial RS485 communication to the BX-MBIO unit will be the media.
The BX-MBIO remote I/O expansion units feature the following:
• RJ45 Ethernet port for communications via Modbus TCP
• RS485 serial port for communications via Modbus RTU
• Supports up to 8 additional Expansion Modules (Add the discrete or analog I/O you require)
• AC and DC powered units available
• AC powered units include an integral 24VDC auxiliary output power supply
• Power connector and serial port connector included
Let’s get started. Continue Reading!