1 every visit, Troubleshooting, Every visit – Campbell Scientific CS450/CS455 Pressure Transducer User Manual
Page 26: Every two to three years or on a rotating schedule
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CS450/CS455 Pressure Transducer
Periodic evaluation of the desiccant is vital for keeping the vent tube dry. The
CS450/CS455 ships with the desiccant tube attached. To assess the
effectiveness of the desiccant, use one of the following:
• The desiccant in the tube changes color from blue to pink when the drying
power is lost.
• An enclosure humidity indicator such as CSI pn 28878 Humidity Indicator
Card.
7.1 Every Visit
• Collect data.
• Visually inspect wiring and physical conditions.
• Check indicating desiccant or enclosure humidity indicator; service if
necessary.
• Check battery condition (inspect physical appearance and use a keyboard
display, PDA, or laptop to view the battery voltage).
• Check all sensor readings; adjust transducer offsets if necessary.
• Check recent data.
7.2 Every Two to Three Years or on a Rotating Schedule
• Send the CS450/CS455 in for inspection and have it serviced and/or
replaced as needed.
8. Troubleshooting
The most common causes for erroneous pressure-transducer data include:
• poor sensor connections to the datalogger
• damaged cables
• damaged transducers
• moisture in the vent tube
Problem:
Unit will not respond when attempting serial communications.
Suggestion:
Check the power (Red is +V and Black is Ground) and signal (White is SDI-12
Data) lines to ensure proper connection to the datalogger. Check the datalogger
program to ensure that the same port the SDI-12 data line is connected to is
specified in the measurement instruction.
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