Part Number -


HOBO External Temp/RH Data Logger


An external-sensor data logger to measure and record temperature and relative humidity in indoor environments.

Important Information

Requires HOBOware software and a USB cable. (Note: A USB-A to USB-B mini cable is included w/HOBOware Pro USB Drive software purchase). See compatible items below.

Compatible with

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HOBO External Temperature/RH Sensor Data Logger

$235.00 USD
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An external-sensor data logger to measure and record temperature and relative humidity in indoor environments. Ideal for monitoring occupant comfort in office buildings, tracking food storage conditions in warehouses, logging temperature trends in server rooms, and measuring humidity levels in museums.

  • Easy-to-view LCD display
  • Large memory capacity
  • Visual high & low alarm thresholds
  • Burst and Statistics logging modes
  • Compatible with HOBOware and HOBOware Pro software for logger setup, graphing, and analysis

Temperature Sensor

Range: -20° to 70°C (-4° to 158°F)
Accuracy: ±0.21°C from 0° to 50°C (±0.38°F from 32° to 122°F)
Resolution: 0.024°C at 25°C (0.04°F at 77°F)
Response time: 3 minutes, 45 seconds in air moving 1 m/s (2.2 mph)
Drift: <0.1°C (0.18°F) per year

RH Sensor

Range: 1% to 100% RH at -40° to 75°C (-40° to 167°F), non-condensing; 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: 0.01%
Response time: 15 seconds to 90% in airflow of 1 m/s (2.2 mph)
Drift: <1% per year typical
Cable length: 1.83 m (6 ft)


Logger Operating Range
Logging: -20° to 70°C (-4° to 158°F); 0 to 95% RH (non-condensing)
Launch/readout: 0° to 50°C (32° to 122°F) per USB specification

Logging rate: 1 second to 18 hours, 12 minutes, 15 seconds
Logging modes: Normal, Burst or Statistics
Memory modes: Wrap when Full or Stop when Full
Start modes: Immediately, Push Button, Date & Time or Next Interval
Stop modes: When Memory Full, Push Button, or Date & Time
Restart mode: Push Button
Time accuracy: ±1 minute per month at 25°C (77°F)
Battery life: 1 year, typical with logging rate of 1 minute and sampling interval of 15 seconds or greater
Battery type: One 3V CR2032 lithium battery
Memory: 128 KB (63,488 measurements, maximum)
Download type: USB 2.0 interface
Full memory download time: 20 seconds
LCD: LCD is visible from: 0° to 50°C (32° to 122°F); the LCD may react slowly or go blank in temperatures outside this range
Size: 3.66 x 8.48 x 2.29 cm (1.44 x 3.34 x 0.9 in.)
Weight: 30 g (1.06 oz)
Environmental rating: IP50

Description: ce
- The CE Marking identifies this product as complying with all relevant directives in the European Union (EU)


One 184 cm (6 ft.) PVC cable: sensor diameter 1 cm (0.38 in.)

Compatible items

Compliance Certificates

$30.00 USD

NIST Setup & Certifications

$116.00 USD
$182.00 USD
$51.00 USD

Protective Enclosures

$47.00 USD

Communication Cables

$18.00 USD


$13.00 USD

Graphing & Analysis

$75.00 USD
$99.00 USD
What's in the box
  • HOBO UX100-023 External Temp/RH Data Logger
  • Command™ strip
  • Double-sided tape
  • Hook & loop strap

HOBO® External Temp/RH Data Logger (UX100-023A) Manual

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Quick Start for the HOBO® U-Series Data Logger

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