YOKOGAWA CM6G, Руководство пользователя

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<8. Troubleshooting>
8-1
IM 11R02A01-02E 5th Edition : Dec. 28, 2016-00
8. Troubleshooting
Two major factors are considered to make large difference between current measuring result and
normally expected ones. One factor is that the process condition is changed, which leads to the
change of gas component . The other one is that the measuring system has some errors. If the
measuring system has some errors, carry out the following troubleshooting in this chapter.
8.1 Gas Sampling Pressure Regulating Section
n
For Town Gas Use
1) See Figure 3.2 and 3.3 Flow Sheet. Check if any blockade or leakage exist in the sampling
line up to the panel.
→If any blockade is found, blow the sampling line by air.
2) Check the filter element of the line filter.
→According to the paragraph 7.2.3, clean or replace.
3) If conditions above mentioned are normal, the pressure gauge (3-2) indicates 8 to 18 kPa.
→When the pump is attached and if the pressure does not indicate normal value even
after opening V-5 fully, the decrease of the suction ability of the pump might be a cause of
the trouble.
→If the pressure reducing valve is attached, and the indication of the pressure gauge
(3-2) does not change even after the operation of the pressure reducing valve (3-8), the
pressure reducing valve may have a defect.
4) When introducing the check gas, confirm the indication of the flowmeter (3-3) is about 10 l/min.
If you need to check only an indication, adjust the flowmeter to approximately 2 to 3 l/min.
→It is due to a defect of the pressure regulator that the flow rate cannot be successfully
set by the pressure regulator (4-1).
5) Confirm the pressure gauge (3-5) indicate approx. 3 kPa.
→If the pressure cannot be satisfactorily set by the pressure reducing valve (3-4), it may
have a defect.
6) When the density meter is attached, confirm the indication of the flowmeter (5-3) is 0.5 to 1 l/min.
→It may be due to the clogging of the gas pipe inside the density meter that no indication
appears on the flowmeter.
7) Confirm the indication of the computing station is about “500”, after setting the indication to
“X3 (G-PRESS)”.
→When the differential pressure setting cannot be executed with the pressure reducing
valve (3-6), it is due to a defect of the pressure reducing valve.
8) For all gas lines, check any leakage at each joint connection.