Extech RHT20 Humidity and Temperature Datalogger

Extech RHT20 Humidity and Temperature Datalogger


The Extech Humidity and Temperature Datalogger records up to 16,000 readings for temperature and 16,000 readings for relative humidity.


  • USB interface for easy setup and data download
  • Selectable data sampling rate: 1 second to 24 hours
  • User-programmable alarm thresholds for relative humidity and temperature
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The Extech Humidity and Temperature Datalogger features a USB interface for easy setup and data download of temperature and humidity readings. The datalogger records up to 32,000 readings, 16,000 for temperature and 16,000 for relative humidity at selectable data sampling rates from 1 second to 24 hours. The user programmable alarm thresholds alert users if a reading exceeds set points. The LCD dispalys current readings, min/max, and alarm status.


Applications include monitoring humidity and temperature levels in warehouses, storage rooms, freezers, shipping vans, and offices. The USB connector easily plugs into a computer for data analysis of temperature and humidity readings.

Notable Specifications:
  • Temperature range: 40 to 158°F (-40 to 70°C)
  • Temperature resolution: 0.1°F/°C
  • Temperature accuracy: ±1.8°F (14 to 104°F), ±3.6°F (all other ranges), ±1.0°C (-10 to 40°C), ±2.0°C (all other ranges)
  • Humidity range: 0 to 100%RH
  • Humidity resolution: 0.1%RH
  • Humidity accuracy: ±3%RH (40 to 60%), ±3.5%RH (20 to 40 & 60 to 80%), ±5%RH (0 to 20 & 80 to 100%)
  • Datalogging interval: 1 second to 24 hours
  • Memory: temperature: 16,000 points; relative humidity: 16,000 points
  • Dimensions: 3.7 x 1.9 x 1.2" (94.4 x 48.9 x 31.2mm)
  • Weight: 3.2oz (90.7g)
What's Included:
  • (1) Datalogger
  • (1) Mounting bracket with combination lock
  • (1) Software CD
  • (1) 3.6V battery
Image Part # Product Description Price Stock Order
Extech RHT20 Humidity and Temperature Datalogger RHT20 Humidity and temperature datalogger
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