DAVIS SPREAD-SPECTRUM RADIO MODEM, Руководство пользователя

Страница: 29 / 36

Power Conservation Mode Page 29
P
OWER
C
ONSERVATION
M
ODE
If a radio modem is operating on solar/battery power, the Timer or AOM will
be used to switch power to the radio, causing it to turn on. The radio will not
answer any incoming communications unless the Timer or the AOM turns it
on.
✦
AOM Power Saving
The AOM enables the RM at 5 minutes past each even-numbered hour
(using the station console’s clock) and keeps it enabled for 4 minutes.
When a communication is received, the RM remains enabled during the
data transfer and for 2 minutes after the last communication ends.
✦
Timer Power Saving
The user may set the Timer to any desired intervals. Any communication
in progress when the Timer switches off will be interrupted.
C
HARGE
B
UDGET
When using the RM in a solar/battery-powered station, one must limit the
power drawn by the RM. The means limiting the time that the RM is on,
enabled to receive calls, and limiting even more severely the duration of calls.
The worksheets below help you to calculate the charge drain per day and the
charge gain per day (from the solar panel). The ratio between these two num-
bers makes it possible to compare the effects of various timing plans.
Charge Drain per Day
The worksheet below will help you calculate the charge drain per day for vari-
ous power on and transmission times.
For each system component, write the amount of current drawn (in Amps) in
the Current column and the number of minutes per day the component is “on”
in the Time On column. Multiply the current drawn by the number of minutes
to determine the drain caused by that component each day. Add the individual
drain figures together to determine the total drain per day for the entire system.
✦
Line A (Console, SIM/junction box & WeatherLink)
The Weather Monitor II, with junction box and WeatherLink, draws 16
mA (0.016A) continuously (1440 minutes per day). The GroWeather,
Energy EnviroMonitor, and Health EnviroMonitor, with sensor interface
module (SIM) and WeatherLink, draw 18 mA (0.018A) continuously
(1440 minutes per day).
C
OMPONENT
C
URRENT
T
IME
O
N
D
RAIN
L
INE
(A
MPS
) (
MIN
/
DAY
) (A
MP
-
MIN
)
Console, SIM/junction box & WeatherLink ______ 1440 ______ A
Alarm Output Module/Timer ______ ______ ______ B
RM On 0.180 ______ ______ C
Total System Drain per Day = A+B+C: ______ Amp-min