acceed: compact modbus module for smart metering
Smart Metering, also known as “Intelligent Metering“, is playing an increasingly important role in small and medium-sized applications. One example of this is consumption data recording in all sizes of residential complexes, commercial buildings and other commercial properties. Here, the Smart Metering is either integrated in the central building technology or it provides the measurement data to administration bodies or billing centres via the Internet as a standalone solution. In accordance with its nature, one of the core tasks of Smart Metering is naturally data acquisition and subsequent data transfer. The new data acquisition module RIO-2010 was developed especially for these tasks and, together with the micro PC Matrix-505 from the same manufacturer, can form an application which is ready for operation.
The new data acquisition module RIO-2010 supports the TCP and RTU modbus protocols. Its integrated AJAX Web interface enables fast and easy configuration using a Web browser. Furthermore, it supports the new MQTT protocol, also known under its former name SCADA protocol. MQTT (Message Queue Telemetry Transport) is an open messaging protocol for M2M which enables the transfer of telemetry data as messages between devices, also within restricted networks or in case of long delay periods. Therefore, the protocol is ideally suitable for communication in networks with a low bandwidth.
The RIO-2010 module is equipped with the 1-wire bus from Maxim for recording temperature data. 16 insulated digital inputs and 8 relay outputs can be used to control peripheral devices. Alarms can be configured via the Web interface, equally E-mail messages and switching processes. The RIO-2010 MQTT can send messages, protocol events and activate relais in alarm status.
In connection with the fanless industrial micro PC Matrix-505, the RIO module is a compact application for consumption and environmental data monitoring which is immediately available for operation. The Matrix-505 offers two 10/100 Ethernet interfaces, two USB 2.0 host connections as well as a microSD slot for memory cards up to 32 GB.
An ARM9 processor with 400 MHz works in the fanless Matrix 505 metal casing. Its working memory is 128 MB. For the extension of the flash memory, a microSD slot which enables capacities of up to 32 GB is available. Connected in the voltage range from 9 to 48 VDC, the Matrix 505's power consumption is around a mere 3 watts. This energy and hence cost efficiency from the hardware side is accompanied by the use of open source software. Linux 2.6.38 and the C/C++ tool chain are pre-installed. With its dimensions of 108 × 78 × 24 mm, the device is space-saving and suitable for installation in surroundings with restricted space such as switch cabinets and cable ducts.
The RIO-2010 module is also suitable for assembly in switch cabinets (on top-hat rails) and can be operated using direct current from 9 to 48 V. The serial interface is executed as a screw connector terminal. LEDs signalise the respective relay status. The admissible ambient temperature for operation is 0 to 70 °C.