VEGA PLICSMOBILE T61 - Manual (Page 21)

21
6 Battery operation and power saving mode
PLICSMOBILE T61 • External GSM/GPRS radio unit
37700-EN-130228
The solar module comes ready to use with a 5 m connection cable.
The free cable end is led through the screw connection into the
electronics chamber of the PLICSMOBILE. You can find the details on
connection in chapter "Connecting to power supply". The black core
is connected to terminal 1(+), the brown core to terminal 2(-).
Note:
Make sure that the two cores of the connection cable are energized
when the solar module is not covered. Avoid a shortcircuit during
mounting and conenction. This should also be avoided when shorten-
ing the cable, if necessary.
6.5 Battery sizing
When selecting an external battery/accumulator, the following points
must be observed:
Power consumption in power saving mode:
If a battery or an accumulator is used which cannot be automatically
charged cyclically, then the power saving mode should be activated.
With an operating voltage of e.g. 12 V, a standby power consump-
tion of 0.3 mW must be taken into account. With an assumed lifetime
of e.g. one year, the requirement is approximately 2.6 Wh, which
corresponds to a battery capacity of 0.22 Ah at 12 V. The standby
power consumption with specific operating voltages is stated in the
"Technical data".
Power requirement complete measurement cycle incl. meas-
ured value transmission:
A measurement cycle lasts approximately 60 to 120 seconds (de-
pendent on sensor type and network quality) and includes automatic
switching on of the sensor (HART multidrop mode with 4 mA),
recording of the measured value, measured value transmission and
a return to the power saving mode. During this time, approximately
20 mWh of energy is required. For example, with one measurement
per day, this adds up to approx. 9.6 Wh per year, which corresponds
to a battery capacity of approx. 0.8 Ah at 12 V.
Examples for battery capacity depending on the number of
transmission cycles
Number of mes-
sages/day
Annual consumption PLICSMOBILE
Standby energy
demand
Energy demand
for message
transmission
Required battery
capacitance with
12 V
1 2.6 Wh 9.6 Wh 0.8 Ah
2 2.6 Wh 16.8 Wh 1.4 Ah
4 2.6 Wh 32.4 Wh 2.7 Ah
8 2.6 Wh 61 Wh 5.1 Ah
24 2.6 Wh 178.8 Wh 14.9 Ah
Connection