Ametek 3050-RM, User Manual

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1-6 | 3050-RM Moisture Analyzer
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NOTE
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NOTE
Verifying the Analyzer
The verify process is used to correct for aging characteristics of the sen-
sor assembly and potential fouling of the sensor by components of the
sample stream. By measuring the response of the sensor to an internally
generated “moisture standard,” any variations in sensor performance can
be effectively compensated for. During the verification operation, a new
span factor is calculated for the sensor, and this value is then applied for
all subsequent readings.
AMETEK recommends performing a verification cycle monthly.
However, no verification cycle should be performed during the startup
of the analyzer. It is recommended to allow the analyzer and internal
moisture generator to stabilize for a period of 24 hours after applying
power, before running a verification cycle.
Changing Gases
If you are selecting a different gas, the analyzer will need time to purge
the intenal volumes and to stabilize flow. To prevent false alarms from
occurring during this time, the display on the analyzer will read New Gas
and the analyzer will automatically purge itself. This purge period lasts
for forty minutes. During this period, the Data Valid contact is opened
and the flow alarms are suppressed.
You can abort this purge process by pressing the Verify key, scrolling
to Abort and then pressing Enter. If the process is aborted, normal
sampling will resume after the completion of the current measure-
ment cycle.
Dew/Frost Point Measurements
Dew point values are calculated from the moisture concentration mea-
surements (PPMV) and the sample or process pressure. For temperatures
below 0 °C, the 3050-RM uses equations to determine the water vapor
pressure over ice, rather than over super-cooled water. Thus, the 3050-RM
reports a frost-point temperature consistent with the physical form of the
condensed phase in a real process stream.
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Water in super-cooled liquid state will only exist as a transient species,
as the first bit of condensate starts to form on a smooth-chilled surface
(i.e., the true method of measuring a dew point).