Onset HOBO U23 Pro v2 Temp/RH Loggers
Features
- Weatherproof housing for use in outdoor or condensing environments
- Small-diameter external sensor versions for measurements in tight spaces
- Optic USB interface for fast and reliable download
- Expedited repair and warranty service
- Lifetime technical support
- More
| Image | Part# | Product Description | Price | Stock | Order | |
|---|---|---|---|---|---|---|
 | U23-004 | HOBO U23 Pro v2 internal temperature/external temperature logger, 6 ft. cable | $165.00 | Check Availability | ||
 | U23-003 | HOBO U23 Pro v2 internal temperature/2x external temperature logger, 6 ft. cable | $200.00 | Check Availability | ||
 | U23-001A | HOBO U23 Pro v2 internal temperature/relative humidity logger | $190.00 | Check Availability | ||
 | U23-002A | HOBO U23 Pro v2 external temperature/relative humidity logger, 6 ft. cable | $225.00 | Check Availability | ||
| Image | Part# | Product Description | Price | Stock | Order | |
|---|---|---|---|---|---|---|
 | BASE-U-4 | HOBO optic USB base station | $140.00 | 5 Available | ||
 | U-DTW-1 | HOBO waterproof shuttle | $280.00 | 3 Available | ||
 | BHW-PRO-DLD | HOBOware Pro Software for Windows and Mac, download only | $75.00 | Check Availability | ||
 | BHW-PRO-USB | HOBOware Pro Software for Windows and Mac, USB drive | $99.00 | Check Availability | ||
 | BHW-PRO-CD | HOBOware Pro Software for Windows and Mac, CD | $99.00 | Check Availability | ||
 | RS3-B | Solar radiation shield | $75.00 | Check Availability | ||
 | DESICCANT1 | Small desiccant for U23 & UA-001/2/4 loggers, pack of 25 | $13.00 | Check Availability | ||
 | U23-CAP | U23 UV protective cap, pack of 5 | $22.00 | Check Availability | ||
 | COMPLIANCE_CERT | Compliance certification | $25.00 | Check Availability | ||
The HOBO Pro v2 logger’s environmentally rugged case is designed for years of reliable use in outdoor applications. It has enough memory to record over 42,000 12-bit measurements.
The logger uses an optical USB communications interface (via a compatible shuttle or base station) for launching and reading out the logger. The optical interface allows the logger to be offloaded without compromising the electronics. The USB compatibility allows for easy setup and fast downloads.
| Temperature Sensor | |
| Operation Range | U23-001A internal sensor: -40 to 70°C (-40 to 158°F) U23-002A external temperature sensor: -40 to 70°C (-40 to 158°F) U23-003 and U23-004 external sensors: -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 | U23-001A and U23-002A: ±0.25°C from -40 to 0°C (±0.45 from -40 to 32°F), ±0.2°C from 0 to 70°C (±0.36 from 32 to 158°F) U23-003 and U23-004: ±0.21°C from 0° to 50°C (±0.38°F from 32° to 122°F); see Plot A |
| Resolution | U23-001A and U23-002A: 0.04°C (0.072°F) U23-003 and U23-004: 0.02°C at 25°C (0.04°F at 77°F); see Plot A |
| Response Time (Typical to 90%) |
U23-001A internal sensor: 10 minutes in air moving 1 m/sec U23-002A external temperature sensor: 3 minutes, 45 seconds in air moving 1 m/sec U23-003 and U23-004 external sensors: 3 minutes in air moving 1 m/sec; 30 seconds in stirred water |
| Drift | U23-001A and U23-002A: <0.01°C (0.018°F) per year U23-003 and U23-004: <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 (Typical to 90%) |
U23-001A: 40 minutes in air moving 1 m/sec with protective cap U23-002A: 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) |
| Materials | All models: ASA styrene polymer housing and mounting clamp; polypropylene protective cap; Buna-N o-ring(s); U23-001A, U23-002A only: ASA styrene polymer RH sensor cap; modified hydrophobic polyethersulfone membrane |
| Cables | U23-001A: No cables U23-002A: One 184 cm (6 ft) PVC cable; sensor diameter 1 cm (0.38 in.) U23-003: Two 184 cm (6 ft) PVC cables; sensor diameter 0.5 cm (0.20 in.) U23-004: One 184 cm (6 ft) PVC cable; sensor diameter 0.5 cm (0.20 in.) |
| 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 |
- HOBO U23Â Pro v2 Temp/RHÂ Logger
- Clamp and mounting screws
- UV protective cap
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