This data logger can measure and store humidity/temperature readings automatically. It has a large LCD that can display realtime readings and logging information.This unit can start a sound and light alarm if exceeds the user set limits. More professional applications can be provided by the unique PC software DGraph under Windows xp/7/8 (32/64 bits). User can easily use the software to setup and download data to PC via USB. And user can view, analyse and print the data, or export other fi le formats(txt, xls, csv, bmp, jpg). 

• Portable, precise, compact and low cost
• USB interface directly communicate with PC for setup and data download
• Unique and uniform PC control software: DGraph
• User can set access password fo each data logger
• Start logging method: Immediately, Button, Start at
• Replaceable lithium battery and data is not lost if exhausted

Model DWL-20 DWL-21 DWL-20E DWL-21E
RelativeHumidity Measurement Range 0 to 100%RH 0 to 100%RH 0 to 100%RH 0 to 100%RH
Accuracy(Typ.) ±3%RH ±2%RH ±3%RH ±2%RH
Resolution(Typ.) 0.1%RH 0.1%RH 0.1%RH 0.1%RH
Temperature Measurement Range "-35 to 80°C
(-31 to 176°F)" "-35 to 80°C
(-31 to 176°F)" "-40 to 125°C
(-40 to 257°F)" "-40 to 125°C
(-40 to 257°F)"
Accuracy(Typ.) ±0.5°C (±0.5°F) ±03°C (±0.5°F) ±0.5°C (±0.5°F) ±0.3°C (±0.5°F)
Resolution(Typ.) 0.1°C (0.2°F) 0.1°C (0.2°F) 0.1°C (0.2°F) 0.1°C (0.2°F)
Sensor Location Internal Internal External External
Memory Capacity 32,000 32,000 32,000 32,000
Sample Rate 2s to 24h 2s to 24h 2s to 24h 2s to 24h
PC Software DGraph software and USB driver required (Included in CD)
Power Supply Rechargeable Lithium Battery, or USB interface to Power
Dimentions 120mm×74mm×24mm(4.8"×2.9"×0.9")
Case Material and Weight ABS; Approx. 130 grams(4.59 oz)