User`s guide

Chapter 2 ___________________________________________________________ Product Overview
VAISALA ________________________________________________________________________ 13
CHAPTER 2
PRODUCT OVERVIEW
This chapter introduces the features, advantages, and the product
nomenclature.
Introduction to DPT145
Vaisala Multiparameter Transmitter DPT145 for SF
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Gas is a digital
transmitter with a non-isolated RS-485 output. Its compact size makes it
well suited for integration into OEM systems.
DPT145 is always delivered with an integrated mechanical adapter:
DILO DN20, DILO DN8, ABB Malmkvist, or Alstom G1/2". The
connection between the adapter and the transmitter is helium leak tested
at the factory.
DPT145 combines online measurement of dewpoint, pressure, and
temperature. DPT145 also calculates four other quantities, including SF
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density.
Table 3 Output Parameters of DPT145
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
Pressure, absolute
P
bara
psia
Pressure, normalized to 20 °C
(68 °F)
Pnorm
bara
psia
Density
Rhoo
kg/m
3
kg/m
3
Temperature
T
ºC
ºF
* When the dewpoint is below 0 °C, the transmitter outputs frostpoint for T
d