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SiemensDuct Temperature & Humidity Sensors

Siemens Humidity Sensor: Duct Mount, Flange Mount, 100 mA to 5 A/24 V AC/DC

The Siemens QFM81.2 is a duct-mount humidity sensor with a flange-mount housing and included mounting flange. It measures relative humidity from 15 to 95% and provides a temperature signal output of 100 mA to 5 A at…

SKU 3G-OTH-68802

Brand

Siemens

Item

Humidity Sensor: Duct Mount, Flange Mount, 100 mA to 5 A/24 V AC/DC

Category

Duct Temperature & Humidity Sensors

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Technical Specifications

Siemens

Manufacturer Part Number

QFM81.2 

Type

Flange Mount, 100 mA to 5 A/24 V AC/DC, Fiberglass Reinforced PPS 

Display

No Display 

Includes

Mounting Flange 

Housing Type

Flange Mount 

Product Type

Duct Humidity Sensor 

Mounting Location

Duct Mount 

Temperature Signal

All-Polymer 24 V AC/DC 

Relative Humidity Range

15 to 95% 

Temperature Signal Output

100 mA to 5 A 

Electrical Connection Type

Screw Terminals 

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Siemens Products

3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Siemens QFM81.2 is a duct-mount humidity sensor with a flange-mount housing and included mounting flange. It measures relative humidity from 15 to 95% and provides a temperature signal output of 100 mA to 5 A at 24 V AC/DC, using all-polymer sensing technology. The unit features screw terminals for electrical connection and a fiberglass-reinforced PPS housing.

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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