DM70 Handheld Dewpoint Meter contains a Measurement Indicator (MI70) and the handheld dewpoint probe DMP74. In pressurized environments, the actual process pressure value must be set for DM70. More information can be found from DM70 User Guide: DM70 User Guide M010091EN-G www.vaisala.com/sites/default/files/documents/DM70_User_Guide_in_English.pdf p.35 Measurement Indicator (MI70) is also compatible with DPT146 Dewpoint and Pressure Transmitter for Compressed Air. DPT146 combines online measurement of dewpoint and pressure. The dewpoint measurement is continuously pressure compensated using the measured pressure. You would need a connection cable between MI70 and DPT146: Vaisala order code: 219980 DPT146 Dew Point and Pressure Transmitter Datasheet B211159EN-J www.vaisala.com/sites/default/files/documents/DPT146-Datasheet-B211159EN.pdf
Your device is NOT measuring the water dew point. Your device is a moisture sensor which uses the moisture content information to calculate the water dew point. It would help if you, as a manufacturer, make accurate claims. Definition of water dew point: The temperature at which water undergoes a phase transition from liquid to vapor phase. So the only way to MEASURE water dew point is to have a surface which can be cooled until condensation happens; i.e. a chilled-mirror device.
Hi Rob, you are correct that our dewpoint sensors use a capacitive polymer technology rather than chilled-mirror technology. Our DRYCAP capacitive polymer sensors provide highly accurate dewpoint readings for their stated measurement ranges. If you have any concerns about this technology, our applications team will be more than happy to provide you with more technical information and test data to demonstrate the accuracy and stability of this measurement technology.
How does the DM70 know the total pressure of the process (necessary to compute dew point) ?
Thank you for your question. I have forwarded it to our specialist, and we will reply to you as soon as possible.
DM70 Handheld Dewpoint Meter contains a Measurement Indicator (MI70) and the handheld dewpoint probe DMP74. In pressurized environments, the actual process pressure value must be set for DM70. More information can be found from DM70 User Guide: DM70 User Guide M010091EN-G www.vaisala.com/sites/default/files/documents/DM70_User_Guide_in_English.pdf p.35
Measurement Indicator (MI70) is also compatible with DPT146 Dewpoint and Pressure Transmitter for Compressed Air. DPT146 combines online measurement of dewpoint and pressure. The dewpoint measurement is continuously pressure compensated using the measured pressure. You would need a connection cable between MI70 and DPT146: Vaisala order code: 219980
DPT146 Dew Point and Pressure Transmitter Datasheet B211159EN-J www.vaisala.com/sites/default/files/documents/DPT146-Datasheet-B211159EN.pdf
Your device is NOT measuring the water dew point. Your device is a moisture sensor which uses the moisture content information to calculate the water dew point.
It would help if you, as a manufacturer, make accurate claims.
Definition of water dew point: The temperature at which water undergoes a phase transition from liquid to vapor phase.
So the only way to MEASURE water dew point is to have a surface which can be cooled until condensation happens; i.e. a chilled-mirror device.
Hi Rob, you are correct that our dewpoint sensors use a capacitive polymer technology rather than chilled-mirror technology. Our DRYCAP capacitive polymer sensors provide highly accurate dewpoint readings for their stated measurement ranges. If you have any concerns about this technology, our applications team will be more than happy to provide you with more technical information and test data to demonstrate the accuracy and stability of this measurement technology.
Moist