Campbell Scientific AVW200-series Vibrating Wire Interfaces - Manual (Page 10)

AVW200-series 2-Channel Vibrating Wire Spectrum Analyzer Modules
The eliminated parameters are:
• Number of steps
• Number of cycles
• Time of Swept Frequency
These parameters are now part of the AVW200 internal operating system and
require no user input. The user only needs to input the lower frequency range,
upper frequency range, and excitation voltage of the sensor.
Read more! Detailed programming information is provided in Section 6.
The AVW200 returns five or six values per measurement. The first value is
the vibrating wire frequency in Hz. The sixth value is the optional thermistor
measurement on Ohms. Values two through five are diagnostic information
giving an indication or validation of the measurement.
(1) = Frequency in Hertz
(2) = SignalStrength in mV_RMS
(3) = Signal/Noise Ratio (unitless)
(4) = Noise Frequency Hz
(5) = DecayRatio (unitless)
(6) = Thermistor output in Ohms of resistance (see Section 2.2, Temperature)
The on-board diagnostics should be monitored to determine faulty wiring,
incorrect frequency range, sensor degradation over time, or to determine faulty
sensors.
Read more! Information on how to use the on-board diagnostics is
provided in Appendix F.
2