Screw-in humidity sensor for dew point monitoring

Many industrial gas-supply systems rely on precise low humidity control to prevent water contamination. Water levels are maintained below a setpoint to avoid condensation, which in turn could lead to biofilm, corrosion, or material damage.

HYT939K5 Module for dw point monitoring

IST AG has designed a factory-calibrated humidity module specifically for continuous monitoring of low humidity levels below 10%RH. With the HYT939 K5-Module a fast and highly accurate RH/T measurement can be integrated directly into existing electronic control systems without the unnecessary cost of an auxiliary transmitter.

The HYT939 K5 Module has a unique price-performance ratio and is suitable for condition monitoring in humidity sensitive environments such as ultra-dry air and compressed air supply systems, including medical grade compressors. It is ideal for the monitoring of inert atmosphere for lasers, semiconductor components or metal additive manufacturing as well as pneumatic systems, including precise robotic tools.

A compact assembly with extension cable and screw-in housing makes gas tight mounting without any pressure loss a simple task. The standard HYT939 K5 humidity sensor assembly enables affordable dew point monitoring below -40°C Td and can be custom-calibrated upon request.



Selected specifications:




Measuring ranges

0..10% RH



+/-1% (5..10%RH)


Response time t63:      

< 4 s

Digital interface:         

I2C bus Protocol

Housing Thread:         


Supply voltage:

2.7 V to 5.5 V (Current. < 22 µA at 1Hz measuring rate)