Siemens SITRANS LU150 - Troubleshooting Guide; Unreliable Echo Troubleshooting

SITRANS LU150
Operating Instructions, 03/2016, A5E34590123-AB
33
Troubleshooting
7
7.1
Troubleshooting
The echo is not reliable and the
LU150 is waiting for a valid echo
before updating the measurement.
Probable causes are:
•
Material or object in contact with sensor face
•
The LU150 is too close to the fill point
•
The LU150 is not perpendicular to the liquid surface
•
Change in level too fast
•
Measurement out of range
•
Foam on liquid surface
•
High level of vibration in the mounting structure
•
Level inside the blanking zone
The 'Waiting' period has expired. Investigate the probable cau
s-
es listed above.
Refer to
Speed of response (Page 29) or Fail-safe timer
(Page 31) for duration of 'Waiting' periods.