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: PROFIBUS PA profile structure
- C Appendix C: Communications via PROFIBUS
- D Appendix D: Certificates and Support
- 13 List of abbreviations
- 14 LCD menu structure
- Glossary
- Index
Glossary
SITRANS LR250 (PROFIBUS PA)
256 Operating Instructions, 01/2014, A5E32221386-AB
beam angle
the angle diametrically subtended by the one-half power limits (-3 dB) of the microwave beam.
beam spreading
the divergence of a beam as it travels through a medium.
blanking
a blind zone extending away from the reference point plus any additional shield length.The
device is programmed to ignore this zone.
capacitance
the property of a system of conductors and dielectrics that permits the storage of electricity when
potential differences exist between the conductors. Its value is expressed as the ratio of a
quantity of electricity to a potential difference, and the unit is a Farad.
confidence
see Echo Confidence.
damping
term applied to the performance of a device to denote the manner in which the measurement
settles to its steady indication after a change in the value of the level.
dB (decibel)
a unit used to measure the amplitude of signals.
derating
to decrease a rating suitable for normal conditions according to guidelines specified for different
conditions.
dielectric
a nonconductor of direct electric current. Many conductive liquids/electrolytes exhibit dielectric
properties; the relative dielectric constant of water is 80.