Yokogawa digitalYEWFLO (DY) - Manual (Page 107)

<12. TROUBLESHOOTING>
12-1
IM 01F06A00-01EN
12. TROUBLESHOOTING
CAUTION
Please avoid replacing the amplifi er unit from the case, and the vortex shedder bar. When these procedures
are needed, please contact the nearest Yokogawa offi ce.
12.1 Large Errors or Unstable Output
Are the parameters
configured correctly at
operating conditions?
Is straight lengths of
pipeline stable?
No
Yes
Yes
Was a faulty area
found with self-diagnosis?
No
No
Does gaskets protrudes?
Yes
Yes
‡,IDEXLOWLQLQGLFDWRULVDWWDFKHG
check the display of the error code.
‡&RQQHFWDKDQGKHOGWHUPLQDODQG
check self-diagnostic.
Is there a snapping
sound from the flowmeter ?
Yes
Is digitalYEWFLO
properly grounded?
No
No
Does the value in
"K34:VORTEX FREQ."
undergo a lot of
changes?
Yes
Normal
No
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Yes
Yes
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Note 1:
Note 2:
This is the temperature and pressure at digitalYEWFLO
mounted place.
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the right statement.
No
Refer to Section 6.5
"Self-Diagnostic (Error
&RGH/LVW" and check
for recovery measures.
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parameters
correctly
&KHFNWKHDYLWDWLRQ
refer to Section 13.4
"Sizing."
Ground
digitalYEWFLO.
This case is due to
coating of stuff
vortex shedder bar.
&KHFNWKHSLSLQJ
inner surfaces.
Ensure the straight
OHQJWKVRISLSHOLQH
UHIHUWR&KDSWHU
"INSTALLATION."
Replace the
gasketsUHIHUWR
&KDSWHU
"INSTALLATION".
12.2 The Indication Goes to Zero at Certain Time
When this problem occurred, the cause is suspected of deterioration of sensor sensitivity and turbulent of fl uid
fl ow due to coating on the shedder bar and fl owmeter inner tube.
How to cope with this problem
1) Refer to Section 11.5 “Vortex Shedder Removal,” take out the Vortex Shedder bar and clean it.
2) If there is the coating on inner tube of the fl owmeter, remove the fl owmeter body from adjacent pipes and
clean it.