P652 Offset Correction; P655 Propagation Factor - Siemens SITRANS L Series Operating Instructions Manual

Parameter assignment
7.20 Range calibration (P652 to P655)
7.20.1

P652 Offset correction

A fixed offset value that is added to the reading as a correction to the measurement.
Values
7.20.2

P655 Propagation factor

The value used to compensate for changes in microwave velocity due to propagation within
a metal stillpipe, instead of in free space.
Values
Pipe size (I.D.)
50 mm (2")
80 mm (3")
100 mm (4")
150 mm (6")
200 mm (8")
Contact your Siemens representative for other sizes and propagation factor numbers.
1)
The propagation factor is constant for a given pipe diameter, or can be determined by
comparing the radar distance reading to the actual process material distance (measured
from the reference point). For the reference point, see SITRANS Probe LR dimensions
(Page 84).
Example:
①
Actual distance / SITRANS probe LR distance= p.f. (propagation factor)
Using the readings shown:
10.42 m / 12.6 m = 0.827
Enter the propagation factor: 0.827
58
SITRANS Probe LR distance
Range
Default
Range
Default
Propagation Factor
0.827
0.915
0.955
0.980
0.990
–99999 to 99999
0.000
0.3000 to 1.5000
1.000
1)
SITRANS Probe LR with mA/HART
Operating Instructions, 05/2019, A5E32337711-AC