Onset
Pro v2 External Temp Data Logger
A weatherproof data logger with an external soil/water temperature sensor on a 6-foot cable, for applications where just one temperature probe is required. Also includes an internal temperature sensor.
Documentation
Data SheetUser Manual
Highlighted Features
- Weatherproof housing for use in outdoor or condensing environments
- High accuracy
- Small-diameter external sensor versions for measurements in tight spaces
- Optic USB interface for fast and reliable download
- Compatible with HOBOware and HOBOware Pro software for logger setup, graphing, and analysis
Specifications
| Measurement | U23-001A Internal Sensor | U23-002A External Sensor | U23-003 and U23-004 External Sensors |
|---|---|---|---|
| Operation Range | -40 to 70°C (-40 to 158°F) | -40 to 70°C (-40 to 158°F) | -40 to 100°C (-40 to 212°F), with tip and cable immersion in fresh water up to 50°C (122°F) for one year |
| Accuracy | ±0.25°C from -40 to 0°C | ±0.25°C from -40 to 0°C | ±0.21°C from 0° to 50°C (±0.38°F from 32° to 122°F); see Plot A |
| ±0.2°C from 0 to 70°C | ±0.2°C from 0 to 70°C | ||
| Resolution | 0.04°C (0.072°F) | 0.04°C (0.072°F) | 0.02°C at 25°C (0.04°F at 77°F); see Plot A |
| Response Time | 10 minutes in air moving 1 m/sec | 3 minutes, 45 seconds in air moving 1 m/sec | 3 minutes in air moving 1 m/sec; 30 seconds in stirred water |
| Drift | <0.01°C (0.018°F) per year | <0.01°C (0.018°F) per year | <0.1°C (0.18°F) per year |
| Relative Humidity Sensor | U23-001A, U23-002A only |
|---|---|
| Operation Range | 0 to 100% RH, -40° to 70°C (-40° to 158°F) |
| Exposure to conditions below -20°C (-4°F) or above 95% RH may temporarily increase the maximum RH sensor error by an additional 1% | |
| Accuracy | ±2.5% from 10% to 90% RH typical to a maximum of ±3.5% including hysteresis at 25°C (77°F); below 10% and above 90% ±5% typical |
| Resolution | 0.05% |
| Response Time | 40 minutes in air moving 1 m/sec with protective cap |
| 15 seconds in air moving 1 m/sec | |
| Drift | <1% per year typical |
| Logger | |
|---|---|
| Operation Range | -40° to 70°C (-40° to 158°F) |
| Real-time Clock | ±1 minute per month 0° to 50°C (32° to 122°F) |
| Battery | 1/2 AA, 3.6 Volt lithium, user-replaceable (HP-B) |
| Battery Life (Typical Use) | 3 years with 1 minute or greater logging interval |
| Memory (Non-Volatile) | 64K bytes memory (approx. 21,000 temperature and RH measurements) |
| Environmental Rating | Electronics housing is NEMA 6P equivalent (tolerant of brief submergence); Units with RH sensors are NEMA 4 equivalent (splash-resistant) |
| Launch Modes | Immediate start; delayed start |
| 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 |
| Offload Modes | Offload while logging; stop and offload |
| Battery Indication | Battery voltage can be viewed in status screen and optionally logged in datafile. Low battery indication in datafile. |
| Weight | U23-001A: 57 g (1.5 oz); U23-002A: 118 g (3.1 oz); U23-003: 138 g (3.7 oz); U23-004: 102 g (2.7 oz) |
| Dimensions | Housing measures 10.2 × 3.8 cm (4.0 × 1.5 in.) |
| NIST Certificate | Temperature certificate available for additional charge |
Applications
In what environment does this data logger operate?
This data logger operates in an outdoor environment.
What measurements does this data logger support?
The U23-004 data logger supports the following measurement: Temperature