Siemens 7MF4.33 Series, Руководство пользователя

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SITRANS P DS III (7MF4.33.. 7MF4.34.. 7MF4.35..)
A5E03434626-03, 06/2013
17
Assembly on 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.
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 level Δp
MA
Start of scale value
h
O
Upper filling level 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.
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')
h
U
Lower filling level Δp
MA
Start of scale value