Campbell Scientific RAWS-P Remote Automated Weather Station - Manual (Page 16)

RAWS-P Remote Automated Weather Station
4.2.3 Troubleshooting
If a problem is suspected, check the sensor cable. Disconnect the connector
and use a digital volt meter (DVM) to check the resistance between Pin A
(sensor signal) and Pin C (sensor ground). The resistance should read as an
open circuit until you move the rain gage tipping mechanism where the magnet
swings past the reed relay. Try connecting a substitute sensor. Obtain an
RMA number before returning this sensor to Campbell Scientific for repair.
Consult the TE525-L manual for more information. NOTE
4.3 Solar Radiation
4.3.1 General Description
The Apogee Pyranometer (pn CS300-LQ) measures incoming solar radiation
with a silicon photovoltaic detector mounted in a cosine-corrected head. The
detector outputs current; a shunt resistor in the sensor converts the signal from
current to voltage. During the night, the CS300-LQ may read slightly negative
incoming solar radiation. The negative signal is caused by RF noise.
4.3.2 Wiring
The CS300-LQ attaches to the connector labeled SOLAR RAD SDI-12; this
connector is color coded green. The pyranometer sensor is internally wired
from the RAWS connector panel to the CR1000 datalogger.
TABLE 4-3. SOLAR RAD SDI-12 Connector (color coded green)
Connector Pin Description CR1000 Terminal
A Solar Sensor + 3H
B Solar Sensor - 3L shorted to
C Solar Sensor Ground
D SDI-12 Ground G (used for a second SDI-12
sensor)
E SDI-12 Signal C5 (used for a second SDI-12
sensor)
F SDI-12 12 V 12V (used for a second SDI-12
sensor)
4.3.3 Troubleshooting
If a problem is suspected, check the sensor cable. Disconnect the connector
and use a DVM to check the voltage between Pin A Solar Sensor (+) and Pin B
Solar Sensor (-). The voltage should be 0 to 200 mV for 0 to 1000 W m
-2
radiation. No voltage indicates a problem with either the photodiode or the
shunt resistor, both of which are potted in the sensor head and cannot be
serviced. Try connecting a substitute sensor. Obtain an RMA number before
returning this sensor to Campbell Scientific for repair.
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