Vaisala DMP6 Dew Point Probe


  • Measures humidity at high temperatures up to +350 °C (+662 °F)
  • Dew point measurement range −25 … +100 °C (−13 … +212 °F) Td/f
  • Dew point measurement accuracy up to ±2 °C (±3.6 °F) Td/f
  • Sensor purge provides superior chemical resistance
  • Condensation-tolerant
  • Modbus RTU over RS-485
  • Compatible with Indigo transmitters and Insight PC software
  • Traceable calibration certificate

Dpstar is a leading supplier of environmental measurement sensors for temperature, relative humidity, pressure, dew point, CO2, and other environmental condition monitoring for industrial process application and research. Since the ’90s, we earned a reputation as a trusted partner to our clients through our commitment and dedication. We are an authorized distributor and supplier of measuring sensors solutions from renowned manufacturers Vaisala. Vaisala is a global leader in environmental and industrial measurement. Building on 80 years of experience, Vaisala provides observations for a better world. Vaisala is a reliable partner for customers around the world, offering a comprehensive range of innovative observation and measurement products and services.

Vaisala DRYCAP Dew Point and Temperature Probe DMP6 are designed for in-line humidity measurement in industrial drying applications with very high temperatures and a wide dew point range. A high-temperature tolerance is achieved using a passive cooling set that conducts heat away from the probe and reduces the temperature to within the optimal range for the sensor. DMP6 incorporates the Vaisala DRYCAP sensor, which is accurate, reliable, and stable. The sensor is condensation-resistant and immune to particulate contamination, oil vapor, and most chemicals. Sensor warming minimizes the risk of condensation accumulating on the sensor. If the DRYCAP sensor does get wet, it dries rapidly and recovers its swift response time. In low-humidity conditions, the sensor will auto-calibrate to ensure accurate measurement. DMP6 is part of the Indigo family and is compatible with Indigo500 and Indigo200 series transmitters. It can be used with the Vaisala Insight PC software for data visualization, easy probe configuration, and self-calibration.


Key Benefits

Measure Dew Point Directly In Very Hot Processes

DMP6 is built for in-line dew point measurement in very hot processes, between 100…350 °C (+662 °F). Best measurement performance is achieved at process temperatures between 100 °C and 350 °C. The cooling system has no moving parts, and requires no additional power or cooling utilities, so there is no risk of sensor damage due to mechanical cooling failure. The installation is simple, as the probe can be directly placed in the process. With in-line measurement, there is no need for a sampling system or sample line trace heating.

Vaisala DRYCAP Sensor For Accurate & Reliable Measurements

The Vaisala DRYCAP sensor is accurate, reliable, and stable. It is condensation-resistant and is immune to particulate contamination, oil vapor, and most chemicals. Sensor warming minimizes the risk of condensation accumulating on the sensor. If the DRYCAP sensor does get wet, it will rapidly dry and recover from getting wet. Due to the unique auto-calibration functionality accurate and stable measurement is ensured.
The chemical purge involves periodic heating of the sensor to remove harmful chemicals. In environments with high concentrations of chemicals and cleaning agents, it helps to maintain measurement accuracy between calibration intervals.

Use standalone or with an Indigo Transmitter

The DMP6 is part of the Vaisala Indigo family, so it can also be used with the Vaisala Indigo series transmitters. The transmitters offer various additional benefits such as display for data visualization, easy access to probe configuration, as well as more extensive options for automation system connectivity, supply voltage and wiring. Built-in Modbus RTU over RS-485 output means that the DMP6 can be used as a standalone device, and can be easily integrated into third party systems. Whether using the DMP6 standalone or with an Indigo transmitter, it can be connected to the Vaisala Insight PC software for easy field calibration, probe configuration and device analytics.


Measurement Performance
Dew point
Sensor DRYCAP 180S
Measurement range −25 … +100 °C (−13 … +212 °F) Td/f
Accuracy ±2 °C (±3.6 °F) Td/f
Response time 63 % [90 %]:
From dry to wet 5 s [10 s]
From wet to dry 45 s [5 min]
Mixing ratio
Measurement range (typical) 0 … 1000 g/kg (0 … 7000 gr/lbs)
Accuracy (typical) ±12 % of reading
Operating Environment
Operating temperature range of probe head 1) +100 … +350 °C (+212 … +662 °F)
Operating temperature range of probe body −40 … +80 °C (−40 … +176 °F)
Storage temperature −40 … +80 °C (−40 … +176 °F)
Measurement environment For air, nitrogen, hydrogen, argon, helium, and oxygen 2)
IP rating IP66
1) Installation of cooling fins on the cooling set the operating temperature range. See the operating range graph.
2) Consult Dpstar if other chemicals are present. Consider safety regulations with flammable gases.
Inputs & Outputs
Operating voltage 15 … 30 V DC
Current consumption 10 mA typical, 500 mA max
Digital output RS-485, non-isolated
Protocols Modbus RTU
EU directives EMC Directive (2014/30/EU)
RoHS Directive (2011/65/EU)
EMC compatibility EN 61326 1, industrial environment
Type approvals DNV GL certificate no. TAA00002YT
Compliance marks CE, China RoHS, RCM
Output Parameters
Dew point temperature (°C) Water concentration (ppmv)
Dew/frost point temperature (°C) Water concentration (wet basis) (vol %)
Dew/frost point temperature at 1 atm (°C) Water mass fraction (ppmw)
Dew point temperature at 1 atm (°C) Water vapor pressure (hPa)
Mixing ratio (g/kg)
Mechanical Specifications
Connector M12 5-pin A-coded male
Probe weight 500 g (1.10 lb)
Cooling set weight 3.50 kg (7.72 lb)
Probe cable length 2 m (6.56 ft)
Probe AISI 316L
Probe body AISI 316L
Cable jacket FEP
Cooling set Stainless steel and aluminum
Cooling set DMP246CS
Indigo USB adapter 1) USB2
1) Vaisala Insight software for Windows is available at


Vaisala DMP6 Dew Point Probe_DpstarGroup