Vaisala DMT143 - Manual (Page 11)

Chapter 2 ___________________________________________________________ Product Overview
VAISALA _________________________________________________________________________ 9
CHAPTER 2
PRODUCT OVERVIEW
This chapter introduces the DMT143 transmitter and its features.
Introduction to DMT143
Vaisala DRYCAP
®
Dewpoint Transmitter DMT143 is a small and
lightweight dewpoint transmitter suitable for a wide range of OEM
applications. The DMT143 is easy to install and the mechanics have been
designed for harsh environments requiring protection against dust, dirt
and splashed water.
DMT143 uses a DRYCAP
®
polymer sensor for dewpoint measurement.
DRYCAP
®
technology has low maintenance needs due to its excellent
long term stability and durability against condensation. The calibration
interval of the DMT143 is two years.
Table 3 Output Parameters of the DMT143
Parameter Abbreviation Metric Unit Non-Metric
Unit
Dewpoint/frost point temperature Tdf ºC ºF
Dewpoint/frost point temperature,
converted to atmospheric pressure Tdfatm ºC ºF
ppm moisture, by volume H20 ppm ppm
NOTE When dewpoint is below 0 °C, the transmitter outputs frostpoint for Td.
Dewpoint temperature in atmospheric pressure (T
d/f
atm) is a calculated
parameter that presents the dewpoint the gas would have at atmospheric
pressure. For this calculation to provide accurate results, it is important to
have the correct pressure setting stored in the transmitter. This setting is
specified on the order form, and it can be changed using the RS-485 line
or DM70 hand-held dewpoint meter.