Elgas DATCOM, Operating Instructions Manual

Page: 102 / 228

6
Operating the Device
100
Information about signal strength at the location of the device. The Modem Status
command does not measure the signal strength. If this information appears on the
display, it is the data ascertained at the time when the modem last logged on to the
network. The strength is stated in dBm and in %. Comparison table - see Table 12
3 IP Address
For GPRS communication, the IP address of the device is displayed.
4 Modem Error 19 )
The code of the last modem error is displayed if an error occurred. The meaning of the
error according to its numeric code is specified in Table 13.
5 Error Date and Time 19 )
For modem error, the date and time of the last error is displayed.
6.8.3.2 Signal Testing
After selecting this option (the modem must be set in the device parameters, it can be turned off),
the device turns on the modem power supply, initializes the modem and measures the signal
strength after connecting to the mobile network. (The sequence
2
modem off, modem on,
modem init, modem connected is run). The time limit for measuring the signal
3
is 120 seconds.
The minimum recommended RSSI value for GPRS communication is -85 dBm (i.e. 45%). Under
this value, the device displays error number 10 (see Table 13). In addition, low GSM/GPRS signal
levels significantly reduce the reported battery life of the modem.
Note:
The number 1 in the top right corner of the display shows the time in seconds to the end of
measurement.
RSSI [dBm] -51 -61 -71 -81 -91 -101 -113
RSSI [%] 100.00 83.87 67.74 51.61 35.48 19.35 0.00
RSSI [rel] 31 26 21 16 11 6 0
Table 12 RSSI signal strength conversion table between dBm, %, and relative units
Code Error description
General Errors
0 modem without error indication
1 modem does not respond