User's Manual

7ML19985LT01 SITRANS LR560 (PROFIBUS PA) – OPERATING INSTRUCTIONS Page 113
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B: Troubleshooting
Display shows
S: 0 LOE
antenna malfunction:
• temperature too high
• physical damage
• check temperature in Maximum
Value (3.4.2.)
•relocate
Reading does not
change, but the level
does
SITRANS LR560 processing
wrong echo, i.e. vessel
wall, or structural member
• re-locate SITRANS LR560
• check nozzle for internal burrs or
welds
• rotate instrument 90°
•use Auto False Echo Suppression
(2.4.8.1.) if necessary: see
Auto False
Echo Suppression (2.4.8.1.) on page
118
Measurement is
consistently off by a
constant amount
• setting for Low Calibra-
tion Pt. not correct
• setting for Sensor Offset
not correct
• check distance from sensor refer-
ence point to Low Calibration Pt.
(2.3.5.1.)
•check Sensor Offset (2.3.5.3.)
Screen blank
power error • check nameplate rating against volt-
age supply
• check power wiring or source
Reading erratic echo confidence weak • refer to Confidence (2.4.7.1.)
•useAuto False Echo Suppression
(2.4.8.1.) and Auto False Echo Sup-
pression Range (2.4.8.2.)
material filling • re-locate SITRANS LR560
Reading response
slow
Fill Rate/Min (2.3.6.2.)
setting is incorrect
• increase measurement response if
possible
Reads correctly but
occasionally reads
high when vessel is
not full
• detecting close range
echo
• build up near top of ves-
sel or nozzle
• nozzle problem
• Use the air purge feature to clean the
antenna
•use Auto False Echo Suppression
(2.4.8.1.) and Auto False Echo Sup-
pression Range (2.4.8.2.)
Level reading lower
than material level
• material is within Near
Range zone
• multiple echoes pro-
cessed
• decrease Near Range (2.4.1.): mini-
mum value depends on antenna type
• raise SITRANS LR560
• ensure Algorithm (2.4.5.1.) is set to tF
(trueFirst echo)
Operation Troubleshooting (cont’d)
Symptom Cause Action