Siemens sitrans PROBE LU - Appendix F: PROFIBUS PA Profile Structure; PROFIBUS Level Device Design; Block Model Overview; Level Transducer Block (LTB)

A5E32337695 SITRANS Probe LU (HART) – OPERATING INSTRUCTIONS Page 49
Parameters
P650 Offset Calibration
Calibrates Empty (P006) if the reported level is consistently high or low by a fixed amount
(stored in P652).
Before using this feature, verify the following parameters are correct:
•Empty (P006)
• Temperature (P664)
Offset Calibration
Begin with a steady level.
1. Press the measurement key to display the calculated reading.
2. Repeat step 1 at least five times, to verify repeatability.
3. Measure the actual reading (use tape measure).
4. Key in the actual value, and press ENTER .
The deviation between the entered Empty (P006) value and the calibrated Empty value is
stored in Offset Correction (P652).
P651 Sound Velocity Calibration
Calibrates the speed of sound constant.
Use P651 under the following conditions:
• The acoustic beam atmosphere is other than air.
• The acoustic beam atmosphere temperature is unknown.
• The reading accuracy is acceptable only at higher material levels.
For best results, calibrate with the level at a known value close to empty.
Values
Range –99999 to 99999
Related
•P006 Empty
• P652 Offset Correction
• P664 Temperature
Values
Range –99999 to 999999
Related
• P653 Velocity
• P654 Velocity at 20
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