Hygro-Thermometer/Datalogger SDL500

The SDL500 records data on an SD card in Excel format. Relative Humidity, Temperature, Dew Point, and Wet Bulb measurements. Adjustable data sampling rate. Stores 99 readings manually and 20M readings via 2G SD card. Type K/J Thermocouple input for high temperature measurements. Large backlit dual LCD display. Record/Recall Min, Max, Data Hold and Auto power off functions. Complete with 6 x AA batteries, SD card, carrying case and Humidity/Temperature probe.

The Extech SDL500 Hygro-Thermometer/Datalogger is capable of measuring relative humidity from 5% to 95% and air temperature from 0˚C to 50˚C. This allows it to calculate dew point from -25.3˚C to 48.9˚C and wet bulb temperature from -21.6˚C to 50˚C. Additionally it can also measure temperature from -100˚C to 1300˚C via a type K thermocouple or -100˚C to 1200˚C via a type J thermocouple.

Up to two measurements can be shown simultaneously on the Extech SDL500’s backlit digital screen. Data hold and min/max recording are both available. As a datalogging instrument, the thermohygrometer can store up to 99 readings manually or up to 20M readings on the supplied 2GB SD card. The user can set a sampling rate between 1s and 3,600s. The SD memory card can easily be transferred to a PC and readings are saved in an Excel ready format.

The Extech SDL500 comes supplied with accessories including batteries, an SD card, a carry case and a humidity/temperature probe. It is covered by a three-year warranty.

  • Relative humidity: 5% to 95%
  • Air temperature: 0˚C to 50˚C
  • Dew point: -25.3˚C to 48.9˚C
  • Wet bulb: -21.6˚C to 50˚C
  • Temperature via type K or type J thermocouples
  • Datalogging for 20M readings
  • Excel readings saved to 2GB SD card
  • Sampling rate of 1s to 3600s
  • Three-year warranty
What’s In The Box?
  • Extech SDL500 Hygro-Thermometer Datalogger
  • 6 x AA batteries
  • SD card
  • Carry case
  • Humidity/temperature probe
  • Instructions for Extech SDL500


Data Sheet

Dew Point
-25.3 to 48.9 °C
Dew Point Max Resolution
20M data records using 2G SD card
Relative Humidity
5% to 95%
Relative Humidity Basic Accuracy
Relative Humidity Max Resolution
Temperature (Air)
0 to 50 °C
Temperature (Air) Basic Accuracy
±1 °C
Temperature (Air) Max Resolution
Temperature (Type J) Basic Accuracy
-100 to 1200 °C
Temperature (Type J) Max Resolution
±(0.4% + 1 °C)
Temperature (Type K) Basic Accuracy
Temperature (Type K) Max Resolution
-100 to 1300 °C
Temperature (Type N)
±(0.4% + 1 °C)
Temperature (Type N) Basic Accuracy
Wet Bulb
-21.6 to 50 °C
Wet Bulb Max Resolution
182 × 73 × 47.5mm
6 × AA (1.5V) batteries
3 years
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