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#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 […]
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, […]
FAQ#066 – Why opening the file of log .CSV of OMNIAlog/miniOMNIAlog in French with Microsoft Office Excel some “strange” characters are visualized instead of some letters?
The cause of this is problem is that Excel opens the CSV files with an incorrect encoding. In the CSV files in French, there are some particular characters (example: “é”, “à”) that, to be correctly visualized, need the encoding UNICODE UTF-8. This encoding is not that of default of Excel, so the file is codified […]
FAQ#065 – What kind of cable I have to use if I want to connect OMNIAlog to a PC using a LAN cable?
For a direct connection between PC and OMNIALOG, the right cable to use is a CROSSED cable. However, it could happen that also using a STRAIGHT LAN cable, it is possible to establish the connection with OMNIAlog. This occurs because from 2011 it has been realized a function called Auto-MDIX, that is available on some […]
FAQ#064 – If I’m using the 3G/2G modem connected on port RS232 of OMNIAlog, can I simultaneously use the LAN connection, too?
No, when you use the modem connected on port COM RS232, OMNIAlog is configured (through its webserver) to transmit the traffic on serial port. This could cause connection problems if you connect the PC on the LAN port of OMNIAlog. To use the communication on LAN port, it is necessary to disconnect the RS232 cable […]