Rotronic HygroLog HL20 Compact Humidity Temperature Data Logger

The HL20 and HL21 are accurate humidity temperature data loggers designed for recording ambient conditions in indoor areas such as research laboratories, high-tech manufacturing facilities and warehouses, storage areas and containers for sensitive goods, museums, office buildings, etc.

The HygroLog HL-20/21 has a large memory of up to 20,000 data points and a long battery life allowing you to record through your most demanding applications. In addition to recording humidity and temperature it has the option of recording dew/frost points. All recorded data is date and time stamped. The accuracy of the HygroLog HL-20/21 is unparalleled at 0.8%RH and 0.2°C. If it is essential that your recorded data be accurate and reliable then the HygroLog HL-20/21 is your match.

• Model HL20: records up to 20,000 pairs of relative humidity and temperature values
• Model HL21: records up to 20,000 pairs of temperature values
• Internal sensors (no apparent probe)
• Humidity range: 0 to 100 %RH (non condensing)
• Optional LC display
• Non-volatile EEPROM memory
• -10 to 60°C (14 to 140°F) – models with LC display: 0 to 50°C (32 to 122°F)
• Accuracy at 23 °C: ± 0.8 %RH and 0.1 °C
• Calibration and adjustment functions
• English or metric unit system
• Real time clock powered for up to 4 hours without batteries
• Programmable alarm function (out-of-limit value)
• Automatic sensor failure alarm
• Status indicator (green and red LED). The green side of the LED flashes every 5 seconds when logging is active. The red side of the LED flashes every 5 seconds when a measured value is out of limits or when the logger requires attention (low battery, memory full, major sensor failure – such as open or shorted sensor)
• Display Sleep function: substantially extends the lifetime of the battery
• Simulator function (fixed output signals) for validating the recording function
• Power: 3 x AA batteries (1.5V)

Long term recording of humidity and temperature measurements is essential in many production, storage, transportation, display and test applications as well as in buildings and museums. They provide valuable information on the levels and variation of humidity and temperature which can have a significant impact on people, materials and objects.

• Rotronic HL20 Datasheet.pdf
• Rotronic HL20 Manual.pdf