Siemens SITRANS LG250 Operating Instructions Manual page 18

Standpipes
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Fig. 9: Mounting in a bypass tube - Position of the spacer or the centering weight
1 Rod probe with spacer (PEEK)
2 Cable probe with centering weight
3 Spacer (PEEK) on the gravity weight of a cable probe
h Measurable tube section
Note:
Measurement in a standpipe is not recommended for extremely adhe-
sive products. In case of slight buildup, you should choose a bypass
tube with bigger diameter.
Instructions for the measurement:
•
The 100 % point in bypass tubes should be below the upper tube
connection to the vessel.
•
The 0 % point in bypass tubes should be above the lower tube
connection to the vessel.
•
A false signal suppression with installed sensor is generally rec-
ommended to achieve the best possible accuracy.
Standpipes or surge pipes are normally metal tubes with a diameter
of 30 ... 200 mm (1.18 ... 7.87 in). Up to a diameter of 80 mm (3.15
in), such a pipe corresponds to a coax measuring probe. It does not
matter if the standpipe is perforated or slotted for better mixing.
Measuring probes can be mounted in standpipes up to DN 200.
SITRANS LG250 - Operating Instructions
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PBD-51041053
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