Ametek 3050-AMS, Руководство пользователя

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1-4 | 3050-AMS Moisture Analyzer
3. The 3050-AMS sample system’s design provides a means of chal-
lenging the analyzer with a known source of dry gas to validate the
baseline readings and to compensate for any minor changes in back-
ground offsets. As such, the Model 3050-AMS is designed to deliver
reliable, long-term performance from the QCM-based sensor.
Sample flow
In the normal operation of the 3050-AMS analyzer, the zero module (the
section enclosed in the dotted line in Figure 1-2) is turned off so that the
sample gas enters the analyzer and passes through diaphragm valve 2
(DV2). After exiting DV2, the flow splits into two paths: the sample path
and the reference path. The sample path flows through the first propor-
tional valve (PSV1) and the reference path flows through a dryer and
PSV2. The two proportional valves (PSV1 and PSV2) control the flow
rate of the gas streams. They also determine which gas stream (sample or
reference) passes through to the QCM sensor. By measuring the pressure
drop across the capillary tube, the 3050-AMS analyzer provides a feedback
signal (the flow rate of the sample gas) to the proportional valves. As a
result, the 3050-AMS analyzer alternately exposes the QCM sensor to a
controlled flow of the sample and dry-reference gases.
Figure 1-2.
Flow schematic for the 3050-AMS sample manifold.
DRYER
DV1
DV3
DV2
PSV 1
GAS INLET
ZERO GAS
MODULE
CAPILLARY
Dryer
PSV 2
QCM
Sensor
Vent
Pressure
Transducer
Y CAPILLAR
BYPASS FLOW
(OPTIONAL P/N 305497901)