Dragino WSS-25, temperature, humidity, light, and barometric pressure sensor, RS485

The Dragino WSS-25 is a 4-in-1 sensor that simultaneously measures air temperature, relative humidity, illuminance, and air pressure. All measuring elements are housed in a UV-resistant radiation shield, which protects temperature and humidity measurements from distortion caused by direct sunlight. Output is via RS485 using the standard Modbus RTU protocol, allowing the sensor to be operated with both the Dragino WSC2-L weather station and any other Modbus master.

Main Features:

• Four measured variables in one device: temperature, relative humidity, illuminance, and air pressure
• UV-resistant radiation shield for permanent outdoor use
• RS485 with standard Modbus RTU protocol, factory device address 13 (0x0D)
• Can be operated directly on the WSC2-L main unit (standard baud rate 4800)
• Power supply 10 to 30 V DC, maximum power consumption 0.8 W

Specifications:

General

• Supply voltage: 10 to 30 V DC
• Power consumption: max. 0.8 W
• Interface: RS485, Modbus RTU
• Standard baud rate (with WSC2-L): 4800
• Factory device address: 13 (0x0D)
• Scope of delivery: 1 × WSS-25

Temperature

• Measuring range: -40 °C to +120 °C
• Resolution: 0.1 °C
• Accuracy: ±0.5 °C at 25 °C
• Long-term stability: ≤ 0.1 °C per year
• Response time: ≤ 25 s (τ63, at 1 m/s airflow in the housing)

Relative Humidity

• Measuring range: 0 to 99 % RH
• Resolution: 0.1 % RH
• Accuracy: ±3 % RH at 60 % RH and 25 °C
• Long-term stability: ≤ 1 % RH per year
• Response time: ≤ 8 s (τ63, at 1 m/s airflow in the housing)

Air Pressure

• Measuring range: 0 to 120 kPa (0 to 1200 hPa)
• Resolution: 0.1 kPa (1 hPa)
• Accuracy: ±0.15 kPa (±1.5 hPa) at 25 °C and 101 kPa
• Long-term stability: -0.1 kPa per year
• Response time: ≤ 2 s

Illuminance

• Measuring range: 0 to 200,000 lx
• Resolution: 1 lx
• Accuracy: ±7 % at 25 °C
• Long-term stability: ≤ 5 % per year
• Response time: ≤ 2 s

Applications:

• Agricultural weather stations based on the Dragino WSC2-L as a base module for climate and light data
• Frost and disease warning in fruit growing, viticulture, and vegetable farming based on temperature and humidity
• Local weather observation and climate monitoring in municipalities, on company premises, or at schools
• Integration into existing Modbus RTU systems, e.g., PLC or building management systems, for recording outdoor climate and daylight

Documents:

• User Manual