User's Manual
Table Of Contents
- 8 Parameter reference
- 9 Service and maintenance
- 10 Diagnosing and troubleshooting
- 11 Technical data
- 12 Dimension drawings
- 12.1 Threaded horn antenna
- 12.2 Threaded horn antenna with extension
- 12.3 Flanged horn antenna
- 12.4 Flanged horn antenna with extension
- 12.5 Flanged encapsulated antenna (2"/DN50/50A sizes only)
- 12.6 Flanged encapsulated antenna (3"/DN80/80A sizes and larger)
- 12.7 Threaded PVDF antenna
- 12.8 Threaded connection markings
- 12.9 Raised-Face flange per EN 1092-1 for flanged horn antenna
- 12.10 Raised-Face flange per EN 1092-1 for flanged encapsulated antenna
- 12.11 Flat-Face flange
- 12.12 Process connection tag (pressure rated versions)
- A Appendix A: Technical reference
- B Appendix B: Communications via Foundation Fieldbus
- C Appendix C: Certificates and support
- 13 List of abbreviations
- 14 LCD menu structure
- Glossary
- Index
Diagnosing and troubleshooting
10.3 Operation troubleshooting
SITRANS LR250 (FOUNDATION FIELDBUS)
Operating Instructions, 01/2014, A5E32221411-AB
195
10.3
Operation troubleshooting
Operating symptoms, probable causes, and resolutions.
Symptom
Cause
Action
Display shows
level or target is out of range
• check specifications
• check
Low Calibration Pt. (2.3.7.1.)
• increase
Confidence (2.5.9.1.)
Display shows
material build-up on antenna
• clean the antenna
• re-locate SITRANS LR250
Display shows
location or aiming:
• poor installation
• flange not level
• Auto False Echo Suppression
may be incorrectly applied
• check to ensure nozzle is vertical
• ensure end of antenna protrudes from end of nozzle
• review Auto False Echo Suppression (Page 236)
• ensure Auto False Echo Suppression Range is set
correctly
Display shows
antenna malfunction:
• temperature too high
• physical damage
• excessive foam
• multiple echoes
• check temperature in
Maximum Value (3.3.2.)
• use foam deflector or stillpipe
• relocate
• use a defoamer
• set
Algorithm (2.5.7.1.)
to t
F
(trueFirst echo)
Reading does not
change, but the level
does
SITRANS LR250 processing
wrong echo, for example, vessel
wall, or structural member
• re-locate SITRANS LR250
• check nozzle for internal burrs or welds
• rotate device 90°
• use
Auto False Echo Suppression (2.5.10.1.)
• if necessary: see Auto False Echo Suppression
(Page 236)
Measurement is
consistently off by a
constant amount
• setting for
Low Calibration
Point (2.3.7.1.)
not correct
• setting for
Sensor Offset
(2.3.7.3.)
not correct
• check distance from sensor reference point to
Low
Calibration Point (2.3.7.1.)
• check
Sensor Offset (2.3.7.3.)
Screen blank power error
• check nameplate rating against voltage supply
• check power wiring or source
too much load resistance
• change barrier type, or
• remove something from the loop, or
• increase supply voltage