WI-I/O 9-K
v1.9
Page 20
20+km in Australia/NZ (1W RF power permitted). To achieve these distance, at least one site
needs to be elevated on a hill or transmission tower - refer section 3.2 for more information).
2.6
Calculating Power Consumption
The following information
may
be used for calculating power consumption.
Voltage Supply
∆
volts (6 – 30)
WI-BP-I/O-9-K
Battery Pack
mA
mAHr
Quiescent
constant regardless of voltage
0.14
3.4 per day
Each radio
transmission
Transmission time 42msec 6V
12V
24V
30V
700
300
180
150
0.005
per transmission
Analog input
measurement
Externally powered transducer - constant
regardless of voltage
10
Not applicable
(per measurement)
Loop Powered Transducer - 12 mA average
355 /
∆
0.012 x w-time
per measurement
Loop Powered Transducer - 20 mA average
576 /
∆
0.020 x w-time
per measurement
Pulse Input
0 - 10 Hz (Slow Pulse Inputs)
0.0025 x f
0.06 x f per day
> 10Hz (Fast Pulsed Inputs)
0.2
4.8 per day
w-time = warm up time in seconds
f = average pulse frequency in Hz
∆
= supply volts
The overall current or energy requirements may be calculated by using the above figures.
Total energy per day = Quiescent
+
Pulse input (if used)
+
Analog input per measurement x number of measurements per day
+
Radio transmission x number of radio transmissions per day
There is no additional power required for digital inputs.
Where the WI-BP-I/O-9-K battery pack is used, these figures can be used to determine the
expected battery life. A WI-BP-I/O-9-K with new batteries has a capacity of 1.7 amphours (1700
mAHr). If two WI-BP-I/O-9-K’s are connected, the second pack provides an additional 1200
mAHr.
Example:-
An application has one digital input, one pulse input and one analog input. It is powered by a single WI-BP-I/O-9-K
battery pack. Each radio message is configured to transmit two times.
The total power consumed = power for transmi power for analog loop pulse input + quiescent
Power for radio transmissions:-
The configuration parameters, and estimated activity data, for each input are:
