YOKOGAWA ZR22S, User Manual

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<2. Specifications>
2-23
IM 11M13A01-02E
Qa
L
200
100
0
5 10 15
P= 0.5
0
40
30
40
60 80
Po (kPa)
Qa (l/min)
0
-1.0
-0.5
40
60 80
Pg (kPa)
0
8
4
40 60
80
Qg (l/min)
L (m) P (kPa)
P (kPa)
P (kPa)
Po (kPa) : Pressure setting
P (kPa) : Drive pressure (at the ejector entrance)
Pg (kPa) : Suction pressure
Qa (l/min) : Air consumption
Qg (l/min) : Suction flow
L (m) : Distance between the ejector and the pressure
gauge
Needle valve Pressure gauge
Ejector
Po
Air source
Sample Gas
Pg
Qg
Gas pressure : -150 Pa
Air consumption characteristics Pressure setting characteristics
Suction pressure characteristics
Suction flow characteristics
F02-13E.ai
Gas pressure: 0 kPa
Graph 4
Graph 2
Graph 3
Graph 1
< Pressure setting for the ejector for high temperature use >
Pressure supply for the ejector should be set so that the suction flow of the sample gas becomes
approximately 5 L/min.
To set this, proceed as follows:
(1) In Graph 4, draw a horizontal line from the 5 L/min point on the vertical axis (Suction flow:
Qg) toward the gas pressure line to be used, to find the point of intersection. Draw a line
vertically down from the point of intersection to the axis to find the drive pressure, P (at the
ejector entrance).
(2) In Graph 1, determine Po (pressure setting) from L (the distance between the ejector and
the pressure gauge).
(3) Open the needle valve to supply air for the ejector to the pressure gauge until it indicates the
pressure setting, Po.
NOTE
Qg (the suction flow) may require change according to the conditions of use. Refer to Subsection
3.2.2 and Subsection 4.1.4 for details.
Graph explanation
1) Graph 1 is to compensate for pressure loss in piping between the ejector and the pressure
gauge, and find Po (pressure setting).
2) Graph 2 shows correlation between P (drive pressure) and Qa (air consumption).
3) Graph 3 shows correlation between P (drive pressure) and Pg (suction pressure; when the
sample gas inlet of the ejector is closed).
4) Graph 4 shows correlation between P (drive pressure) and Qg (suction flow) for each gas
pressure.
2.7.2 Stop Valve (L9852CB, G7016XH)
This valve mounted on the calibration gas line in the system using ZA8F flow setting unit for
manual calibration.