RasPi Measurement Controller RMC
The RMC enables autonomous recording of measurement values, which are delivered via Ethernet, WLAN, RS485, or RS232. Additionally, the measurement values can be transmitted live to the cloud.
The Measurement Controller offers a simple connection to our standard software Trendows for further processing of the data in real-time.
For the single-board computer Raspberry Pi, we have developed an interface board that provides the following functionalities:
- Integration of measurement modules and measurement boxes with RS485 interface
- Integration of measuring devices with RS232 interface
- Analog and digital signal acquisition via adapted modules
Construction of the RMC
The RMC is delivered as a standalone unit in a DIN rail housing. Upon request, measurement modules can be installed in a larger DIN rail housing.
Execution in a DIN rail housing with a removable top cover. The cover contains two rubber grommets for the passage of cables for the connections behind it.
Accessible from the front:
- 4 USB A sockets
- Ethernet LAN connection
W x H x D: 106 x 91 x 62
Housing from the back with the connector ports for:
- RS485 interface for a serial bus
- RS232 interface
- Power supply
Diverse application possibilities
RS232 interfaces
The serial RS232 interface includes the 5 data lines Rx, Tx, GND, RTS, and CTS. This allows for the integration of measuring devices with hardware protocol.
Communication drivers for some measuring devices are integrated for the interfaces or developed according to customer needs.
RS 485 Bus
The serial RS485 bus interface includes a hardware switching of the data lines. By default, the following bus communication protocols are integrated:
- Gantner Localbus Protocol
- Modbus/RTU
- Advantech ASCII protocol for the ADAM modules
App
Within the RMC configuration, a data file with a maximum of 48 channels can be assembled. The current values of the file are displayed in an app, allowing for on-site monitoring of the measurement values. The app is only available for Android smartphones.
Browser
With the browser of a smartphone or PC, the historical data of the cloud-stored data can be viewed in graphs, x/t diagrams, up to the current point in time. The data corresponds to the created data file. The current results are displayed in tabular form on the website. For further evaluations, the data can be directly exported to an EXCEL spreadsheet.
Data Logger
The data logger function of the measurement program "Mess" saves the data records consisting of 48 channels to the Micro-SD card of the RasPi. A dedicated storage area is created on the memory card for this purpose. Due to the size of today's memory cards, millions of data records can be stored. The reading of the data records can be done with the configuration software ReadRaspi or with TrendChart.
HDMI
Monitors with HDMI input can be connected via the HDMI interface. For our measurement boxes of type MBI32, we can use 5" TS displays to show the measurement and result values. Within the configuration file of the RMC, the display pages can be defined individually. Images for buttons or event displays can be used to visualize results.
Mobile Communication
For data transmission without LAN or WLAN network, the RMC can be expanded with a plug-in mobile communication board or a modem stick.
Integration withTrendChart
TrendChart is a pure evaluation program that reads the data records from the cloud or the RMC. It has been specifically developed to read and display large amounts of data in a short time. Within TrendChart, any events can be filtered out using mathematical and logical functions. More information about TrendChart can be foundhere.
Integration with Trendows
Trendows is used for online communication with the RMC. The communication takes place via Modbus/TCP. All 1024 real values and 1024 bit values of the RMC can be read or sent.
ReadRaspi
ReadRaspi is the communication software for the RMC. It determines which measurement hardware is used and how the measurement values are mathematically processed. With ReadRaspi, the data logger can also be read out in a selectable time range. The data is written directly to an
EXCEL spreadsheet.
Data Transmission to the Cloud
With the WLAN function of the Raspberry Pi, a hotspot operation is possible to establish a network for the wireless transmission of measurement data from multiple measurement points and with the measurement boxes of type MBI.
The RMC is equipped to send data in parallel to our software tool WebData on a web server. WebData stores the data in a database and presents it using a web application.