Campbell CS725, Instruction Manual

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CS725 Snow Water Equivalent Sensor
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the system for a minimum of 48 h. Increase capacity where frequent power
outages are expected.
7.2.1 Solar Powered Sites
The maximum power draw from the CS725 is 180 mA (4.32 Amp-hours) per
day. It is recommended that solar powered systems be designed with a
minimum reserve capacity of 260 Amp-hours. It is important to account for the
power draw from other equipment that may operate from the power supply.
A large reserve capacity is required:
•
As solar panels may become covered in ice and snow, charging may not be
possible for extended periods of time.
•
Battery capacity decreases in cold temperatures.
•
Cold temperatures can significantly reduce battery ability to received a
charge. Generally, very little charging occurs below -30°C.
Solar Panel Size:
Solar panels required to charge the CS725 should be sized according to the
geographic location of installation and total maximum power draw.
7.3 Wiring
The wiring for the CS725 connector-cable assembly is:
TABLE 7-1. CS725 Connection to Datalogger and DB9F-TERM
Colour Connection to
Datalogger Connection to
DB9F-TERM Function
Black G No connection Power Ground
Red +12Vdc No connection Power Source
Green Com Port – Rx Pin 2 RS-232 Tx
(sensor output)
White Com Port - Tx Pin 3 RS-232 Rx (sensor
input)
Clear No connection Shield
Large
Green No connection Battery G Earth Ground
RS-232
Port No connection RS-232 of PC
(DTE) RS-232
Communication