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Appendix L.  RF400/RF410 Average Current Drain Calculations
L-3
EXAMPLE #1  (Remote RF400/RF410 in default standby mode)
There is a Point-to-Point system with base RF400/RF410 and remote
RF400/RF410.  The remote station senses weather conditions and sends low-
resolution data to final storage.  The base station collects 10 data points from
the remote station once per minute.  Both stations are configured for “<4 mA,
½ sec Cycle” (the default standby mode).  The remote station operates on solar
power and we are interested in knowing the average current drain contribution
of the RF400/RF410.  From the above section:
It  = Is + Id + Ir + Ii
Calculating each term:
Is = table mA value = 4 mA
It 
 6.1 mA
The dominant average current drain contributors are the standby mode current
and the “time of inactivity to sleep” currents.  If large quantities of data per
minute were being generated/collected, then Id would become a significant
contributor.  In this example the “time of inactivity to sleep” could be reduced
because only 10 data points are sent per collection.  Try a value of 10 instead
of 50 reducing the Ii contribution from 2 mA to 0.4 mA.
mA
 
0.08
    
mA  
 
73
 
 
ms
 
60,000
ms
 
65
  
mA  
 
73
 
  
(ms)
 
T
(ms)]
 
N
 
2
 
 
(ms)
 
45
[
  
  
Id
=
×
=
×
+
=
mA
 
0.008
  
mA  
 
24
 
  
(ms)
 
60,000
(ms)
 
20
  
Ir  
=
×
=
mA
 
2
  
mA  
 
24
  
  
(ms)
 
60,000
ms
 
5000
  
  
Ii
=
×
=