The Soil Instruments W9 Vibrating Wire Piezometer is a reliable instrument designed to measure pore water pressure in fully or partially saturated soil and rock. With a rugged design that prevents stresses from affecting readings, the W9 remains precise and stable even in challenging environments. Capable of operating within a pressure range of -50 to 4000 kPa, the W9 uses a vibrating wire sensor to convert pressure changes into frequency signals. This signal is immune from cable effects such as moisture, splicing and length variations. The W9 is backed by over three decades of experience in both design and manufacturing. This piezometer has a small diameter and as it is constructed with robust 316 stainless steel, it is capable of long-term monitoring in most environments. The over-voltage surge arrestor provides protection from electrical damage such as lightning strikes. Other features of the W9 include

• Compatibility with most standard data loggers, allowing for real-time data monitoring
• In-built temperature compensation
• In-built thermistors for temperature monitoring

This piezometer is compatible with most standard data loggers and allows for real-time data monitoring.