Campbell RF400, Инструкция по эксплуатации

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Appendix L. RF400/RF410 Average Current Drain Calculations
L-4
EXAMPLE #2 (Base RF400/RF410 in default standby mode)
The base RF400/RF410 in the above example does more receiving and less
transmitting than the remote RF400/RF410 so you might expect less average
current drain, however, the amount of data being transmitted per minute is
small, and the long header required is significant. Here are the results:
It = Is + Ih + Iq + Ir + Ii
Calculating each term:
Is = table mA value = 4 mA
It
≈
6.9 mA
As in Example #1, the standby mode current, long header, and the “time of
inactivity to sleep” currents dominate the average RF400/RF410 current drains,
so the calculated values for remote and base RF400/RF410s are nearly equal.
Larger data collections would make the Ir contribution more significant.
ms) 700 length header" long " (default mA 0.875 mA 73
ms 60,000
ms 700
73
(ms) T
(ms) L
Ih
= = × = × =
mA
mA 0.025 mA 73
(ms) 60,000
(ms) 20
Iq
= × =
mA 0.026 mA 24
(ms) 60,000
ms] 20 (ms) 45 [
Ir
= ×
+
=
50) sleep" to inactivity of time " default (using mA 2 mA 24
(ms) 60,000
ms 5000
Ii
= = × =