Unless you require vented level data, the Level TROLL 400 is for you. This low-maintenance data logger measures and logs water level, water pressure and temperature. Ideal for long-term monitoring at flood-prone or high-humidity sites, the Level TROLL 400 is available in non-vented (absolute) pressure ranges. 3D factory calibration and our unique anti-drift system ensure accuracy, and durable titanium construction is designed to withstand harsh conditions in fresh or saltwater, in either groundwater or surface water environments. 

As part of In-Situ’s shared ecosystem, this versatile instrument easily integrates with accessories and in-well telemetry. Pair with In-Situ’s VuLink telemetry and HydroVu Data Services for powerful remote data access and management. Smart addressing enables you to connect any device to the same data logger without reprogramming to monitor the same parameter. 


3D Factory Calibration

Piezoresistive titanium pressure sensors are calibrated across full pressure and full temperature for accuracy across all field temperatures and certified for NIST® traceable factory calibration.

Low-Maintenance Deployment

Reduce trips to the field with ultra-low-power electronics and long-life batteries. Add telemetry to the system to automate data collection and barometric compensation. Hydrophobic Filters and replaceable desiccants extend deployment and instrument life.

Anti-Drift System

Kevlar-reinforced cables eliminate cable stretching that can appear as drift. Piezoresistive Titanium Sensors maintain their pressure for years. 3D calibration across the full range of pressure and temperature avoids drift across temperature. And premium tight tolerance electronic components hold up over time.


Streamline data management with convenient Log Set-Up and Calibration Assistants, instrument diagnostics, panoramic live data, and seamless translation into multiple languages delivered right to your smartphone or tablet. Instantly access each of your sites, view and share data from anywhere, and receive automatic event alerts.

Shared Ecosystem

Reduce complexity and cost with equipment that works together. All Level TROLL products use the same ecosystem—from handheld to cable to communication.


Surface Water

Monitor inland or coastal water easily and accurately with equipment designed to work together.

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Continuous Groundwater Monitoring

Measure water level and water quality over time at local or regional scales.

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