Vibrating-wire sensor interface

The AVW200 vibrating-wire interface is designed to improve vibrating-wire measurements, reducing noise and improving accuracy. Vibrating-wire technology is used in many sensors, including strain gauges, pressure transducers, piezometers, tilt meters, crack meters and load cells. These sensors benefit a variety of structural, hydrological and geotechnical applications because of their stability, accuracy and durability.

The AVW200 vibrating-wire interface module uses a built-in spectrum analyser to transform from the time domain (time between pulses) to the frequency domain (pulses per second). Using the frequency domain, signals can be separated into their relative frequencies and limits can be set on which frequency range is acceptable as a true signal frequency.

The AVW200 can be used through the SDI-12, RS232 or PakBus network protocol. It has low power consumption (300 µA quiescent and 40 mA active) and a rugged design. Wireless versions are also available, allowing for remote deployment of sensors from the data logger. Programming is easy with data retrieval by a single instruction.

When coupled with the AM16/32B, the AVW200 vibrating-wire interface module can be used by any of the Campbell range of data loggers to measure up 32 single-channel sensors, 16 single-channel sensors with temperature compensation, or 16 dual-channel sensors.

Along with providing noise immunity for vibrating wire sensor measurements, the AVW200 vibrating wire interface module provides advantages that include increased measurement accuracy and resolution, the ability to characterise individual vibrating wire sensors and the ability to monitor and account for long-term sensor drift.