Overview
Only 3×4 cm, this tiny data logger measures temperatures over a wide range, providing 12-bit resolution and ±0.2 °C accuracy. Designed for outdoor and underwater environments, this logger is waterproof to 300 m (1000 ft). An optical USB interface lets you offload data in seconds.
Please note: A solar radiation shield is required to obtain accurate air temperature measurements in sunlight (assembly-required RS1 Solar Radiation Shield or pre-assembled M-RSA Solar Radiation Shield).
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Features
- Onset’s smallest temperature data logger
- Waterproof to 300 meters (1,000 feet)
- Data readout in less than 30 seconds via fast Optic USB interface
Specifications
Temperature Sensor
Operation Range*
-20° to 70°C in air;
-4° to 158°F in air;
maximum sustained temperature of 30°C (86°F) in water*
Accuracy
±0.21°C from 0° to 50°C , see manual for plot
±0.38°F from 32° to 122°F , see manual for plot
Resolution
0.02°C at 25°C , see manual for plot
0.04°F at 77°F , see manual for plot
Response Time
5 minutes in water; 12 minutes in air moving 2 m/sec;
20 minutes in air moving 1 m/sec (typical to 90%)
Stability (Drift)
0.1°C per year
0.18°F per year
Logger
Real-time Clock
±1 minute per month 0° to 50°C (32° to 122°F)
Battery
3 Volt lithium, non-replaceable
Battery Life (Typical Use)
5 years with 1 minute or greater logging interval
Memory (Non-volatile)
64K bytes memory (approx. 42,000 12-bit temperature measurements)
Weight
19.6 g
0.69 oz
Dimensions
3.0 × 4.1 × 1.7 cm (1.2 × 1.6 × 0.68 in.); mounting bail 4.6 mm (3/16 in.) diameter hole
Wetted Materials
Epoxy case
Waterproof
To 305 m (1000 ft.)
Logging Interval
Fixed-rate or multiple logging intervals, with up to 8 user-defined logging intervals and durations; logging intervals from 1 second to 18 hours. Refer to HOBOware software manual.
Launch Modes
Immediate start, delayed start, triggered start
Offload Modes
Offload while logging; stop and offload
Battery Indication
Battery level can be viewed in status screen and optionally logged in datafile. Low battery indication in datafile.
Environmental Rating
IP68
NIST Certificate
Available for additional charge
