Overview
Designed for ecosystem research, protection and restoration, with a compact, rugged, and waterproof design rated for fresh and saltwater environments, the HOBO Bluetooth MX2502 Underwater PAR logger effectively delivers research-grade sensor performance in an easy-to-use, affordable package.
It integrates the LI-COR LI-192 quantum PAR sensor that provides the industry’s highest-accuracy underwater light measurement, plus sensors for temperature and tilt. With both water and air calibration factors, this multiparameter logger provides accurate PAR data in either environment.
This logger is designed to be easily mounted onto third-party wipers like the ZebraTech Hydro-Wiper (sold separately) using the M-CLP clamp, which can be deployed with HOBO’s underwater lowering frame and/or rebar stakes using the M-BRK-2 mounting bracket. Users can deploy this logger in minutes, configure logging intervals via the free HOBOconnect app, which allows you to wirelessly retrieve data with your mobile device, and eliminating the need to take your laptop into the field.
Features
- Provides the highest accuracy data using the LI-192 Quantum sensor, the industry standard for logger calibration with built-in measurement averaging to filter out environmental noise
- Easily attaches to available wipers for keeping the sensor window clear and mounts on available wipers
- Streamlined logger configuration, data offload, data visualization and data sharing, all within the free HOBOconnect app
- Convenient and reliable wireless data offload eliminates having to open loggers, connect cables or bring laptops to wet locations
- Data quality control from a tilt sensor and a water-detect sensor
- Provides PAR data for both water and air calibrations
- Simplifies data management and reduces the amount of equipment you need to offload data with single platform
- Easy data consolidation, access, and visualization with LI-COR Cloud and an optional MX data plan
- Supports optimal aquaculture site selection and design
- Rugged and reliable housing and sensor materials provide years operation in harsh aquatic environments.
- Recalibration options: LI-COR for factory recalibration service or self-calibrating against a precision reference
Specifications
Sensors
Measured parameters: PAR with water calibration, PAR with air calibration, temperature, and tilt angle
Photosynthetically Active Radiation (PAR)
- Range: 0-3000 µmol/m²/s (full sunlight)
- Accuracy: ±5% typical (LI-192 factory calibration)
Wavelengths: 400-700 nm with close-to-ideal PAR response
Cosine Correction: Optimized for both underwater and atmospheric use
Temperature
- Range: -20 to 50 °C (-4 to 122 °F) non-freezing water
- Accuracy: ±0.2 °C
- Resolution: 0.1 °C
Tilt Angle
- Range: 0 to 180° from vertical
- Accuracy: ±5°
- Resolution: 1°
Logger
Logging Interval: User-selectable from 1 second up to 18 hours
Memory Capacity: 195,000 sets of measurements
Water Detect Events: Records events when logger is submerged and when it emerges from the water
Wireless Range: Up to 30.5 m (100 feet) line-of-sight via Bluetooth Low Energy for wireless data download
Enclosure Rating: IP68 up to 30m
Battery: Powered by a factory-replaceable battery with 6-year life at nominal logging interval with Bluetooth off
Operating Environment: -20 to 50C; fresh or saltwater; cannot be frozen in ice
Dimensions: Diameter: 1.695″ ; Length: 7.190″
Weight: 274 g ( 0.604 lb.) Logger only; With packaging 495 g ( 1.091 Lb.)
