L3Harris NARDA AMS-8061, User Manual

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4-14 Point to Point and FTP Communication
How to switch the GSM
modem on
AMS-8061 is equipped with a 4G GSM modem, which power consumption,
especially while transmitting, is very high, if compared with the station
overall consumption.
Additionally, modem transmissions, including communications between
terminal (modem) and network that are not under the user control, generate
E.M. fields that affect the measurement results.
For the reasons above, the modem activity of an E.M field monitoring
device should be reduced to the minimum by switching the modem OFF
whenever convenient.
The GSM modem of AMS-8061 is therefore switched ON/OFF depending
on the user settings and other conditions.
When the modem is OFF it neither consumes power nor generates any
E.M. field. On the other hand, it is not able to receive calls or messages.
It is suggested to program the modem to be OFF for the major part of the
day except times, usually one hour per day or less, to download results and
be able to receive calls and messages. Abnormal situations, like alarm
conditions, will be able, anyway, to switch the modem ON to allow
automatic activities like alarm notifications.
A modem ON, but not communicating, is defined here as to be in “Stand-
by” mode. It consumes some power but it is able to receive calls and
messages.
Short transmissions due to communications between the modem and the
GSM network occur usually every few hours when the modem is in Stan-by
mode.
During transmission the modem power consumption is high and, in the
case of the GSM module, it depends on the quality of the network signal.
On the monitoring station the GSM modem can be switched on in three
different ways:
1.
Programmed (the User decides when the modem has to be switched
on and for how long).
2. Spontaneous (the monitoring station switches the modem on
whenever there is an alarm)
3. Automatic (the monitoring station switches the modem on and off
automatically when certain conditions arise)