Free programmable controller - MIDAM D00201
Free programmable process station equipped with ARM Cortex M4 processor and FreeRTOS operating system. It is suitable for control of small installations or data acquisition. It features Ethernet and RS485 ports, M-Bus port for up to 60 metering devices, three pulse counter inputs as well as integrated web interface.
- Freely programmable PLC
- ARM Cortex-M4 processor
- FreeRTOS operating system
- Communication interfaces – Ethernet (RJ45), RS485 (Modbus RTU), M-Bus
- Integrated web interface
Function
The D00201 controller possesses an embedded FreeRTOS operating system which boots up the runtime with the application. There are three pulse inputs and an M-Bus interface according to EN 1434-3, EN 13757-2 (maximum 60 metering devices) available for data acquisition from various energy meters. There is a RTC backed up with battery, flash memory containing OS, runtime, application, and other necessary data like time programs, setpoints etc., as well as a watchdog. It is also possible to use NVRAM as a backup for key parameters in case of unexpected system shutdown or connectivity drop. The application is created and uploaded in the integrated development environment (IDE). The complexity of application program size depends on number of physical and software data points, amount of function blocks which require more memory (e.g. time schedulers), level of code optimisation, and number of connections the controller is supposed to maintain. It contains Ethernet (RJ45) port and RS485 port for seamless communication with other control devices. The PLC features an integrated web server for remote connection and direct user intervention. The web pages are created in HMI editor, which is included in the package of development programs supplied by the manufacturer. The exported web definition components are uploaded to the PLC through IDE (refer to Web definition in PLC properties).
Application
- Free programmable control of HVAC systems
- Web access and visualisation of HVAC systems
- Data acquisition, processing, and presentation
- Protocol converters with web data presentation
- Common application with advanced networking features
- Water, heat, gas, and electrical energy meter readout for meters with M-Bus communication or pulse output
Programming
The main programming tool is the IDE package which contains I/O editor, graphical editor of the function plan (FBD), structure text editor (according to IEC 61131-3) and compiler. The application program consists of function blocks which are stored in libraries. Those contain analogue and digital functions, mathematical blocks including goniometric functions, time schedulers, alarm blocks, and HVAC specific blocks ( heat recovery, dewpoint calculation, enthalpy, pump switch etc. ). The program can be set up also as structured text ( ST ) or with combination of both types of programming languages. The IDE package contains LCD menu editor as well as web editor ( HMI ).
SCADA system integration
Direct integration into various SCADA systems through wired Modbus TCP, OPC UA, or BACnet/IP (RJ45) protocols is possible.