FAQ#077 – Which are the maximum cable lengths from instrument to datalogger?
The cable lengths depend from many factors, first of all installation and cable protections (screen, earth, etc…). Assuming that instruments are installed in a workmanlike, for the maximum cable lengths should be followed the next suggestions: DIGITAL INSTRUMENTS: see FAQ#73 ANALOGUE INSTRUMENTS: see both downloadable documents.
FAQ#076 – Why it is necessary add a termination resistor to the last digitized sensor of each RS-485 chain?
All SISGEO digitized instruments (IPIs, Tiltmeters, H-Level…) use the RS-485 serial communication protocol The RS485 protocol contemplate a termination resistor. The recommended chain connection is point-to-point (multidropped) nodes as a bus mode (line). Star, ring or multiply network connection are not recommended. SISGEO dataloggers has already a termination resistor assembled (typically 120Ω). On the opposite […]
FAQ#075 – What parameters are saved in SISGEO digital sensors? What information must the Customer provide when ordering?
All SISGEO digital sensors (e.g. IPI, BH Profile, MD Profile, LT Inclibus, Tilt-meter, RDS, H-Level, etc.) use the Modbus communication protocol over RS-485 serial. SISGEO digital sensors are connected to each other with a single signal cable. The parameters that are configured at the factory for each digital sensor are as follows: Upon confirmation of […]
FAQ#074 – Which kind of datalogger is necessary to read a SISGEO digital sensors?
The sensors are read connecting the end cable to a Modbus Master unit (i.e. OMNIAlog or miniOMNIAlog) with RS-485 interface (DCE, Half duplex, no Echo) able to manage communication with SISGEO Modbus RTU communication protocol. SISGEO’s communication protocol is available for the release upon request. The power [W] of power supply must be chosen according […]
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FAQ#073 – Which is the maximum number of digitized sensors (RS-485, Modbus), the maximum number of chains and the maximum length of cable in a RS-485 network?
Last update: October 2021 All the SISGEO digitized sensors utilize a RS485 interface with Modbus protocol. 1.The maximum number of digitized sensors in a RS-485 network are 247 (theoretical) 2.The maximum number of digitized sensors chains that is possible to connect to Modbus master unit (as OMNIAlog or miniOMNIAlog) are 4. 3. About the maximum […]
FAQ#072 – Why pushing RUN in a miniOMNIAlog webpage with 3G/2G modem the local connection with the PC gets lost?
The loss of the local connection with the PC is normal. This happens because the communication “bus” is the same between PC and miniOMNIAlog and between miniOMNIAlog and 3G/2G modem. Therefore, if you start miniOMNIAlog from the web, the communication is directed towards the 3G/2G modem. This allows to the modem to send SMS, e-mail […]
FAQ#071 – Why miniOMNIAlog is supplied through the PC when it is connected through USB?
This feature allows to not consume the internal batteries during the configuration phase or during the data download. In this way, independently from the duration of the activities above described, the internal batteries are used only during the field activities (acquisition, data dispatch etc). This guarantees a superior duration of exercise.
FAQ#070 – If you disconnect the USB cable from miniOMNIAlog, the datalogger resets. Is it normal?
Yes, it is. This takes place because when you connect the PC though USB connection, miniOMNIAlog is powered by the PC. If you disconnect the USB cable, miniOMNIAlog resets to change its supply source and returns to the supply through internal battery or from an external source (solar panel or electrical supply).
FAQ#069 – If miniOMNIAlog is supplied with internal batteries, can it read the digitized sensors SISGEO?
No, in case you have to read the SISGEO digitized sensors, it is necessary to use an additional module of power supply (code 0OMX24V030W). This is necessary to power the instrument with the necessary power supply. This module considers the supply or from solar panel or electrical.
FAQ#068 – Using miniOMNIAlog, is it possible to do acquisitions leaving it connected to the PC?
No, it is not possible. miniOMNIAlog, to do correct measurements, needs to be powered or from the internal battery or from an external power supply (solar panel, electrical supply) to supply to the connected instruments the right tension and current. Leaving connected miniOMNIAlog to the PC through USB cable, the instrument is powered directly to […]
FAQ#067 – Is it possible to avoid the manual configuration of the dial-up remote connection and of the virtual modem necessary to communicate with miniOMNIAlog?
Yes, it is. You have to use the tool “miniOMNIAlog communcation tool” that you could find on the USB pen supplied together with miniOMNIalog and on SISGEO website in the product section. It is not necessary to install the tool on the PC. Once you extracted it in a PC local folder, simply starting it, […]