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Introduction
Thank you for purchasing the state-of-the-art Phymetrix Loop-powered Moisture Analyzer
model
PLMa or PLMaEx or PLMa-Probe-Ex.
These analyzers measure moisture content in gasses in the range -110°Cdp to +20°Cdp and
provide a 4-20mA output linear to the measurement units chosen. The factory default is
4mA= -100°Cdp and 20mA= +20°Cdp. Using the HART interface the defaults can be modified
in value and units (available units: °C & °F dewpoint, ppmV, ppmW, mB H
2
O vapor pressure,
grams of H
2
O / m
3
and Lbs H
2
O /10
6
standard cubic feet in Natural Gas ). The PLMa is a Loop-
Powered Blind (two wire) Transmitter; thus it has no display and the 4-20mA output is
transmitted on the two power pins by consuming power in the range of 4mA to 20mA. In
addition the PLMa is equipped with a HART interface which superimposes a digital
communications signal on the 4-20mA loop.
This User’s Manual describes the functions of these analyzers as well as the operating methods
and handling precautions. There are also some sections that review general knowledge and
concepts of water vapor science. Read this manual thoroughly before using the analyzer. There is
a Quick Setup Manual describing the main functions and basic procedures for performing
measuring operations. Check our website “www.phymetrix.com” for latest versions of
documentation regarding these analyzers.
After reading this manual, keep it easily accessible for future reference. It may come in handy
when there are some challenging measurements to be performed.
Conventions used in this manual:
When using the word “
system
” in this manual we are referring to the user’s system in which
the moisture content is being measured. This could be a simple configuration of a pressurized
gas bottle with a pressure regulator, or a complex system of dryers, filters, regulators, long
tubing/pipes, valves etc.
Check to see that your analyzer has arrived intact with all accessories.
Models: PLMa & cable OR
PLMaEx OR PLMa-Probe-Ex
Save the packing materials at least until you have verified that there is no concealed damage, it
may also be useful for future transportation.
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