Loop Power - Siemens SITRANS LR500 Series Operating Instructions Manual

Preferred algorithm types are marked with an asterisk. They provide the best echo selection
results in most applications. Other algorithms may prdouce better results in specialized
applications, but should only be used after consulting an experienced techincal expert.
Algorithm Algorithm name
abbrevia‐
tion
ALF Area largest first
echo
A Echo area
L Largest echo
F First echo
BLF Best echo of the first
and largest echo
TF True first echo
B.3

Loop power

B.3.1 Loop power
Note
Loop voltage
Loop voltage is the voltage at the terminals of the power supply (not the voltage at the terminals
of the device).
SITRANS LR500 series with mA/HART
Operating Instructions, 03/2024, A5E51099898-AA
Echo determination
Selects the echo (average of widest,
tallest, and first), with the highest con‐
fidence value.
Selects the widest echo above the TVT
curve.
Selects the tallest echo above the TVT
curve.
Selects the first large echo above the
TVT curve.
Selects the echo (best of first and tall‐
est), with the highest confidence value.
Selects the first echo above the TVT
curve.
Applications
• Solids
• General purpose
• Where material return echo is wide and tall,
and where competing smaller echoes chal‐
lenge algorithm "BLF"
• Solids
• Coarse, heaped material
• Distance to material must be greater than
2 m
• Liquids (open vessel)
• Where material return echo is tall
• Liquids (closed vessel)
• Liquids and Solids
• General purpose
• Where material return echo is relatively tall
and sharp
• Liquids (free of obstructions)
• Use to ignore multiple echoes, where confi‐
dence value of first echo is high
Technical reference
B.3 Loop power
203