Introduction to HMM100 Series Humidity Modules - HMM100

The HMM100 series humidity measurement modules are open frame modules intended for integration into environmental chambers and other chambers where high temperature tolerance is important. The modules provide a single analog output channel for relative humidity (RH) or dewpoint (T_d). Dewpoint is the recommended quantity if the measurement environment has significant temperature differences.

Table 1. Quantities Measured by HMM100

Quantity	Range
Relative humidity (RH)	0 ... 100 %
Dewpoint (Td)	-20 ... +100 °C (-4 ... +212 °F)

All HMM100 modules include automatic temperature compensation across the operating temperature range using an integrated Pt1000 sensor. No external temperature compensation should be applied to the output.

HMM100 modules do not incorporate probe heating or chemical purge functionality. If the measurement environment is prone to condensation, or likely to cause chemical contamination of the sensor, other Vaisala instruments may be more suitable to the application.

The cable and probe of the HMM100 are attached at the factory. They should remain connected to the module at all times; do not cut and re-connect the cable.