Emerson Rosemount 1408A Reference Manual page 51

Reference Manual
00809-0200-4480
7.3.4 Level value drops when close to antenna
Level value drops to a lower value when product surface is close to antenna.
Figure 7-4: Symptom
A. Level
B. Time
C. Actual level
D. Reported level
Possible cause
Product surface is within the Upper Null Zone and a disturbance echo is interpreted as the
product surface.
Recommended actions
•
Related information
Change the upper null zone
Reference Manual
A
C
D
Check the setting of the Upper Null Zone.
Service and troubleshooting
B
May 2021
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