Siemens SITRANS LUT400 Operating Instructions Manual page 7

Transferring parameters using LUT400 display lid ...................................................................227
Replacing the Battery ......................................................................................................................228
Decontamination Declaration ........................................................................................................229
Diagnosing and Troubleshooting ...............................................................................231
Communication Troubleshooting ..................................................................................................231
Device Status Icons .........................................................................................................................232
General Fault Codes .........................................................................................................................233
Common Problems Chart ................................................................................................................236
Noise Problems .................................................................................................................................242
Determine the Noise Source ................................................................................................242
Non-Transducer Noise Sources .........................................................................................243
Common Wiring Problems ....................................................................................................243
Reducing Electrical Noise .....................................................................................................243
Reducing Acoustical Noise ..................................................................................................244
Measurement Difficulties ...............................................................................................................244
Loss of Echo (LOE) ..................................................................................................................244
Adjust Transducer Aiming.......................................................................................... 244
Increase Fail-safe Timer Value................................................................................. 245
Install a Transducer with a Narrower Beam......................................................... 245
Fixed Reading ....................................................................................................................................245
Obstructions in the Sound Beam ........................................................................................245
Nozzle Mountings ...................................................................................................................245
Set the SITRANS LUT400 to Ignore the Bad Echo ..........................................................246
Wrong Reading ..................................................................................................................................246
Types of Wrong Readings .....................................................................................................246
Liquid Splashing ......................................................................................................................246
Adjust the Echo Algorithm ....................................................................................................246
Transducer Ringing ..........................................................................................................................247
Echo Profile Display .........................................................................................................................247
Trend Display .....................................................................................................................................247
Technical Data ...............................................................................................................249
Power .........................................................................................................................................249
Performance .............................................................................................................................249
Interface ....................................................................................................................................250
Mechanical ...............................................................................................................................252
Environmental ..........................................................................................................................252
Approvals ..................................................................................................................................253
Dimension Drawings ....................................................................................................255
Appendix A - Technical Reference ............................................................................257
Principles of Operation ....................................................................................................................257
Process Variables ...................................................................................................................257
Transmit Pulse .........................................................................................................................257
Echo Processing ...............................................................................................................................257
Echo Selection .........................................................................................................................258
Time Varying Threshold (TVT)................................................................................... 258
Algorithm ........................................................................................................................ 259
Confidence ..................................................................................................................... 259
Echo Threshold ............................................................................................................. 259
Figure of Merit............................................................................................................... 260
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