Siemens Humidity and Temperature Sensor (QFA3171/QFA3171D)


The Siemens QFA3171 temperature and humidity sensor is for use in ventilation and air conditioning plants where high accuracy and short response times for measuring relative humidity are required. The measuring range covers the entire humidity range of 0...100 %. The instrument has a very high measuring range across the entire measuring range.

The QFA3171 is also available with an LCD display (QFA3171D) to view both temperature and humidity. The sensor can also be outdoor mounted using the AQF3100 accessory. With a wide variety of possible applications and wide range of measurement of both temperature and humidity, the QFA3171 is the ideal solution for your monitoring needs.

Application :

Storage and production facilities in the paper, textile, pharmaceutical, food, chemical and electronics industry, etc.



Indoor swimming-pools

Computer and EDP centers


Specifications :

Operating voltage


DC 13.5...35 V

Measuring range, temperature


0...50 °C, -35...35 °C, -40...70 °C

Measurement range humidity


0...100 % r.h.

Measurement accuracy


Humidity at 0...100 % r.h. and 23 °C: ±2 % r.h., Temperature, at 15...35 °C: ±0.6 K, Temperature, at 40...70 °C: ±0.8 K

Time constant


Humidity: <20 s, Temperature: <8.5 min

Connection, electrical


Screw terminals

Signal output temperature


DC 4...20 mA

Signal output humidity


DC 4...20 mA

Degree of protection


IP65 / IP40

Dimensions (W x H x D)


80 x 144 x 39 mm

Note: For more detailed specifications, please download the additonal documents Download PDF

© 2022 ACE Instruments . All rights reserved!