Campbell Scientific Wireless Sensor Network (CWB100, CWS220, and CWS900) - Manual (Page 46)

Wireless Sensor Network
2. If the initial attempt fails to link to the base station, the CWS sensor will
delay 5 minutes before attempting to link again. The BLUE LED will be
off during this time. The sensor will try to link to the base at a five
minute interval a total of three times.
3. If the 5-minute interval attempt fails to link to the base station, the CWS
sensor will delay one hour before attempting to link again. The BLUE
LED will be off during this time. The sensor will try to link to the base at
a one hour interval a total of four times.
4. If the hourly attempts fail, the CWS sensor will try to connect to the base
station every 12 hours. At the beginning of each 12 hour interval it will
make three attempts spaced 5 minutes apart. This sequence will be
repeated indefinitely.
If the Setup button is not pressed to initiate auto-discovery, the wireless sensor
will automatically begin a search for the base station 12 hours after being
powered.
If discovery has been successful and the base station later loses power, the
wireless sensor keeps making measurements at the same polling interval. It
does not transmit the measured values because it only transmits data when
polled by the CWB100 base station. After 4-12 hours of no communication
with the base station, the sensor will start the autodiscovery mode and follow
the schedule shown above.
6. Testing the Network
Whenever possible it is best to bench test the network before
field installation. NOTE
Test the network by powering the sensors and verifying their RF connectivity.
This is done with the following steps:
1. Configure the wireless sensors (see Section 3 for details).
2. Write the datalogger program (see Section 4 for details).
3. Connect the CWB100 radio base station to the datalogger with the
DATA/A channel wired to the control port specified in the Port parameter
of the CWB100 () instruction.
4. Send the program to the datalogger.
5. Connect the battery pack to the first wireless sensor. When first powered
the red LED light will hold steady for 5 seconds and then turn off. Press
the Setup button on the back of the sensor and hold it in for 8-10 seconds
to force the sensor to start searching for the base station. When the button
is first pressed, the blue LED light will flash 1 to 4 times to indicate the
sensor battery voltage (see Section 5 Button Behavior). After several more
seconds the blue LED will flash about once per second as the sensor
searches for the base station. It may take several minutes for the wireless
sensor to link with the base station. Once the linking has taken place, the
blue LED will stop flashing. From that point on, the blue LED will light
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