Determining the position data

An internal flag is set each time the position cycle expires thus ensuring that the GSM position data will also be determined the next time a connection is established. The position cycle can be selected via the relevant parameter in the "Basic settings" configuration section (see Basic settings). If set to 0, the GSM position data is generated every time a connection is established.

If the 4-Channel Data Logger has been equipped with the optional GNSS receiver "GPS extension " (301408), then the position of the device can be determined using global navigation satellite systems (GPS/QZSS, GLONASS) in addition to the method using GSM cell location. The former guarantees that the determined position is considerably more accurate.

The GNSS receiver is activated by selecting "GPS" mode for the switchable sensor supply VEXT via the "Output channels" configuration section (see Output channels). If this mode has been activated, the switchable sensor supply VEXT in each case is switched on automatically two minutes before expiry of the position cycle until the position cycle has elapsed, to supply the GNSS receiver and is thus not available for any other purposes. If the GNSS receiver could determine the exact position during this time, the GPS position data is saved in the memory of the 4-Channel Data Logger and transmitted to the myDatanet server along with the GSM position data that is definitely generated upon expiry of the position cycle during the next connection. Based on the quality information also included in the data, the server then decides whether the GPS or GSM position data should be used to display the position of the measurement instrument on the server interface. Details on this are provided in "myDatanet Server Manual " (805002).

The "Latitude", "Longitude" and "Elevation" GPS position data are also saved in their own measurement channels (see GPS position data) and can therefore be used in conjunction with the interface of the myDatanet server (e.g. for reports, visualisations, graphics, etc.) and the API.