Siemens LU01 User Manual

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SITRANS LU01 – INSTRUCTION MANUAL
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Measurement Difficulties 
If a measurement difficulty occurs for greater than the Failsafe Timer (P070) setting, LOE 
is flashed alternately with the Reading display. Under certain conditions, a measurement 
difficulty may cause the SITRANS LU01 to lock on to a false echo and report a fixed or 
wrong reading. 
Flashing LOE Display 
If LOE is displayed, ensure that the:
1.
Material (object) surface monitored is within the maximum range of the transducer. 
2.
Transducer (P004) value matches the transducer used. 
3.
Transducer is located and aimed properly. 
(See the Transducer manual for maximum range, mounting and rough aiming 
instructions.) 
For optimum performance, adjust the transducer aiming while monitoring the Echo 
Confidence (P805) for various material levels over the measurement range. When 
complete, set the transducer aiming at the best angle for all levels. 
To display Echo Confidence in the RUN mode:
Press 
 
and hold for 4 seconds (Failsafe Time Left changes to the Short : Long 
Confidence display). 
To display Echo Confidence in PROGRAM mode, access the Echo Confidence (P805) 
parameter.
To update the value displayed after each aiming adjustment... 
Press 
 
(5 times or more to verify stability) 
If the condition persists (despite optimum aiming), optimize transducer performance. (See 
Enhancement Parameters Short Shot Frequency, P840 and Long Shot Frequency, P841). 
Increase the Failsafe Timer (P070) value, if failsafe operation will not be compromised by 
the larger value. 
If LOE is displayed only when a sloped bottom vessel is near Empty, the echo is probably 
being reflected away from the transducer. Install an empty target plate in the bottom of 
the vessel. When exposed (not covered by material), the target plate provides the 
reflective surface representative of an empty vessel. 
Install a longer range transducer, enter the new Empty (P006) distance, and (if necessary) 
optimize aiming and frequency again. 
If a longer range transducer is not available, connect an oscilloscope to the SITRANS 
LU01, (see Enhancement Parameters Scope Displays, P810).