Siemens QFA3101 Relative Humidity Sensor – 0–100% RH, 4–20 mA Output, ±2% Accuracy

General
The Siemens QFA3101 is a high-accuracy relative humidity sensor from the Siemens QFA series, designed for HVAC, ventilation and building automation applications. It measures relative humidity across a range of 0 to 100% RH and provides an active 4–20 mA output signal for connection to compatible building management systems and industrial controllers.

With a specified humidity accuracy of ±2% RH, the QFA3101 supports reliable environmental monitoring in commercial buildings, laboratories, healthcare facilities and industrial environments. Its current-loop output makes it suitable for control systems requiring a standard 4–20 mA measurement signal.

Features
- High-accuracy relative humidity measurement.
- 0–100% RH measuring range.
- ±2% RH measurement accuracy.
- Active 4–20 mA output signal.
- Linear output proportional to relative humidity.
- Fast response time of less than 20 seconds.
- Designed for HVAC and building automation systems.
- Polycarbonate housing.
- Wall-mounted installation.
- Screw-terminal electrical connections.
- Low power consumption.
- Suitable for commercial and industrial environmental monitoring.

Key Specifications
- Brand: Siemens
- Product Family: QFA Series
- Model: QFA3101
- Manufacturer Part Number: QFA3101
- Product Type: Relative Humidity Sensor
- Measurement Parameter: Relative Humidity
- Humidity Measuring Range: 0–100% RH
- Measurement Accuracy: ±2% RH
- Output Signal: Active 4–20 mA DC
- Output Characteristic: Linear, proportional to relative humidity
- Temperature Effect: Less than 0.1% per °C
- Response Time: Less than 20 seconds
- Power Supply: 13.5–35 V DC
- Power Consumption: Less than 1 VA
- Electrical Connection: Screw terminals
- Housing Material: Polycarbonate
- Installation: Wall-mounted
- Housing Protection: IP65
- Measuring Tip Protection: IP40
- Display: Not included
- Temperature Measurement: Not available