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SiemensDuct Temperature & Humidity Sensors

Siemens Humidity and Temperature Sensor: Duct Mount, 32°F to 122°F, Polycarbonate

The Siemens QFM2171 is a duct-mounted temperature and humidity sensor with a plastic housing and screw terminals. It provides a 4 to 20 mA humidity output, a relative humidity range of 0 to 95% with an accuracy of…

SKU 3G-OTH-68652

Also listed as: QFM 2171 · QFM-2171

Brand
Siemens
Item
Humidity and Temperature Sensor: Duct Mount, 32°F to 122°F, Polycarbonate
Category
Duct Temperature & Humidity Sensors
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Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
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Technical Specifications

Siemens
Manufacturer Part Number
QFM2171
Type
32°F to 122°F, Polycarbonate, Single Measurement
Display
No Display
Housing
Plastic
Product Type
Duct Temperature and Humidity Sensor
Humidity Output
4 to 20 mA
Mounting Location
Duct Mount
Temperature Accuracy
±0.50 K
Relative Humidity Range
0 to 95%
Electrical Connection Type
Screw Terminals
Relative Humidity Accuracy
±5% of Full Scale
Compatible Building Automation Protocols
BACnet MS/TP
For Use With Building Automation Systems
Building Automation System Compatible

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Siemens Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Siemens QFM2171 is a duct-mounted temperature and humidity sensor with a plastic housing and screw terminals. It provides a 4 to 20 mA humidity output, a relative humidity range of 0 to 95% with an accuracy of ±5% of full scale, and a temperature accuracy of ±0.50 K. This sensor is compatible with BACnet MS/TP building automation protocols and is designed for use with building automation systems.

Frequently Asked Questions

What is the Siemens QFM2171 duct sensor used for?

The Siemens QFM2171 is a duct-mounted temperature and humidity sensor used in building automation systems to monitor and control HVAC conditions. It provides a 4 to 20 mA humidity output and is compatible with BACnet MS/TP protocols, making it suitable for commercial and industrial environments requiring precise environmental monitoring.

What are the specifications of the Siemens QFM2171?

The Siemens QFM2171 has a relative humidity range of 0 to 95% with ±5% full-scale accuracy, temperature accuracy of ±0.50 K, and a 4 to 20 mA humidity output. It features a plastic housing, screw terminals, and is designed for duct mounting. It is compatible with BACnet MS/TP building automation systems.

Where to buy the Siemens QFM2171 worldwide?

The Siemens QFM2171 is available to order through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we source and deliver this sensor to your location.

How to install the Siemens QFM2171 duct sensor?

Install the Siemens QFM2171 by mounting it in the duct with the sensing element exposed to airflow. Use screw terminals for electrical connections, ensuring wiring matches the 4 to 20 mA output and BACnet MS/TP protocol. Follow standard HVAC sensor installation practices for accurate readings and reliable operation.

Used in

Common applications for Siemens
District cooling plants — LME73 + RWF55 for condenser-water modulation
Inflight catering and food-processing steam boilers — LMG22 with SQN90 air-fuel cross-damper
Hospital steam-plant redundancy — LME41 with QRA2 UV flame detection for dual-fuel boilers
Semiconductor fab process heat — LME23 and SKP55 gas valves on hot-oil heater skids
Container-terminal reefer-deck heating — LMG22 retrofit onto legacy burner racks

Siemens Products

3G Electric supplies Siemens duct temperature & humidity sensors. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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