SITRANS P, DS III series (7MF4.33.. 7MF4.34.. 7MF4.35..)
18
A5E03434645-01, 08/2011
Measurement in a closed container
When taking measurements in a closed container without or with little condensate formation, the negative pressure line is
not filled. Lay the line in such a way that pockets of condensate do not form. Install a condensation container if required.
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Measurement assembly on a closed container (no or little
condensate separation)
Formula:
Start-of-scale value: Δp
MA
= ρ · g · h
U
Full scale value: Δp
ME
= ρ · g · h
O
h
U
Lower filling height
Δp
MA
Start of scale value
h
O
Upper filling height
Δp
ME
Full scale value
p
Pressure
ρ
Density of the measured medium in the
container
g
Acceleration due to gravity
When taking measurements in a closed container with strong condensate formation, you must fill the negative pressure line
(mostly with the condensate of the measured medium) and install a condensate pot. You can cut off the device using the
dual pneumatic block 7MF9001-2.
'
-
K
2
K
8
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OHYHO
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ORZSUHVVXUHOLQH
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K
Y
Measurement assembly on a closed container (strong condensate
formation)
Formula:
Start-of-scale value:
Δp
MA
= g · (h
U
· ρ- h
V
· ρ')
Full scale value:
Δp
MA
= g · (h
O
· ρ- h
V
· ρ')
