Operation Troubleshooting - Siemens SITRANS L Operating Instructions Manual

9.4

Operation troubleshooting

Operating symptoms, probable causes, and resolutions.
Symptom
Display shows
Display shows
Display shows
Display shows
Reading does not
change, but the level
does
Measurement is con-
sistently off by a con-
stant amount
Screen blank
Reading erratic
SITRANS LR200 with PROFIBUS PA
Operating Instructions, 07/2021, A5E32337680-AF
Cause
level or target is out of range
material build-up on antenna
location or aiming:
• poor installation
• flange not level
• Auto False Echo Suppression
may be incorrectly applied
antenna malfunction:
• temperature too high
• physical damage
• excessive foam
• multiple echoes
SITRANS LR200 processing wrong
echo, for example, vessel wall, or
structural member
• setting for Low calibration
point (2.3.7.1.) (Page 95) not
correct
• setting for Sensor offset
(2.3.7.3.) (Page 96) not cor-
rect
power error
too much load resistance
echo confidence weak
Action
• check specifications
• check Low calibration point (2.3.7.1.) (Page 95)
• increase Confidence (2.5.9.1.) (Page 107)
• clean the antenna
• relocate SITRANS LR200
• check to ensure nozzle is vertical
• ensure end of antenna protrudes from end of nozzle
• review Auto false echo suppression (2.5.10.1.) (Page 107).
• ensure Auto False Echo Suppression Range is set correctly
• check Maximum value (3.3.2.) (Page 117)
• use foam deflector or stillpipe
• relocate
• use a defoamer
• set Algorithm (2.5.7.1.) (Page 104) to F (First echo)
• re-locate SITRANS LR200
• check nozzle for internal burrs or welds
• rotate device 90°
• use Auto false echo suppression (2.5.10.1.) (Page 107)
• check distance from sensor reference point to Low calibra-
tion point (2.3.7.1.) (Page 95)
• check Sensor offset (2.3.7.3.) (Page 96)
• check nameplate rating against voltage supply
• check power wiring or source
• change barrier type, or
• remove something from the loop, or
• increase supply voltage
• reduce wire distance or use larger gage wire
• refer to Confidence (2.5.9.1.) (Page 107)
• use Auto false echo suppression (2.5.10.1.) (Page 107) and
Auto false echo suppression range (2.5.10.2.) (Page 109)
• use foam deflector or stillpipe
Diagnosing and troubleshooting
9.4 Operation troubleshooting
147