Siemens Building Technology QFM81.21 Hygrostat 326058-756 With rapid opening and closing

With rapid opening and closing times of less than one second

5 ton reciprocating compressor designed for 208/230V single-phase applications

the SPST contacts open

but specifies rotation can often be adjusted via lead reversal depending on the specific wiring diagram

Siemens Building Technology QFM81.21 Hygrostat 326058-756 With rapid opening and closingThe Siemens Building Technology QFM81. 21 is a commercial grade duct hygrostat designed for precision relative humidity control in HVAC systems. Engineered for both monitoring and regulation, this device features a stabilized sensing strip that ensures superior linearity and long term stability, even in high humidity environments or air contaminated with dust. Unlike baseline models, the QFM81. 21 utilizes an internal setpoint adjuster to prevent