HMP4 Relative Humidity and Temperature Probe


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HMP4 Relative Humidity and Temperature Probe - 1

HMP4 Relative Humidity and Temperature Probe For Pressurized and Vacuum Processes Features • RH accuracy up to ±0.8 %RH • Temperature accuracy up to ±0.1 °C (±0.18 °F) • Temperature measurement range -70 ... +180 °C (-94 ... +356 °F) • Operating pressure 0 ... 10 MPa (0 ... 100 bar) • Sensor purge provides superior chemical resistance • Modbus RTU over RS-485 • Compatible with Indigo transmitters and Insight PC software • Traceable calibration certificate: 6 points for humidity, 1 point for temperature Vaisala HUMICAP® Humidity and Temperature Probe HMP4 is designed for high-pressure applications such as compressed air systems in maritime, breathing air, and industrial applications, where measurement performance and chemical tolerance are essential. Proven Vaisala HUMICAP® Performance Vaisala is the original innovator of the thin-film capacitive humidity measurement technology, which has now become the industry standard in humidity measurement. HUMICAP® technology results from Vaisala's 40-year experience in industrial humidity measurement, providing the best stability, fast response time, and low hysteresis in a wide range of applications. Chemical Purge Minimizes Effects of Contaminants In environments with high concentrations of chemicals and cleaning agents, the chemical purge option helps to maintain measurement accuracy between calibration intervals. The chemical purge involves heating the sensor to remove harmful chemicals. The function can be initiated manually or programmed to occur at set intervals. Flexible Connectivity The probe is compatible with Vaisala Indigo series of transmitters, and it can be used as a standalone digital Modbus RTU transmitter over RS-485 serial bus. For easy-to-use access to field calibration, device analytics, and configuration functionality, the probe can be connected to Vaisala Insight software for Windows®: see insight. Vaisala Indigo Product Family Indigo transmitters offer a variety of connectivity options through analog signals or digital outputs, configurable relays, and wireless (WLAN) configuration interface, providing a suitable solution for all industrial humidity measurements. The cable length between the probe and transmitter can be extended to up to 30 meters. For more information, see

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HMP4 Relative Humidity and Temperature Probe - 2

Technical Data Measurement Performance Relative Humidity Operating voltage Measurement range Current consumption Digital output Sensor options Relative humidity, temperature, dew point temperature, wet-bulb temperature, absolute humidity, mixing ratio, water concentration, water mass fraction, water vapor pressure, enthalpy Factory calibration uncertainty Output Parameters Temperature Measurement range Factory calibration uncertainty 2) Defined against calibration reference. Including non-linearity, hysteresis, and repeatability. Defined as ±2 standard deviation limits. Small variations...

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