Siemens SITRANS DS III series, Compact Operating Instructions

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SITRANS P, DS III series (7MF4.33.. 7MF4.34.. 7MF4.35..)
16
A5E03434631-02, 12/2012
● Easily accessible
● The measuring point must be as close as possible
● Vibration-free
● Within the permitted ambient temperature values
3.4.2 Installation for level
Note
Seals are required for the installation. The seals must be compatible with the medium to be measured.
Seals are not included in the delivery.
Procedure
To install the transmitter for level, proceed as follows:
1.
Attach the seal to the container's mating flange.
Ensure that the seal is centrically positioned and that it does not restrict the movement of the flange's seal diaphragm in
any way as otherwise the tightness of the process connection is not guaranteed.
2. Screw on the transmitter's flange.
3. Observe the installation position.
3.4.3 Connection of the negative pressure line
Assembly on an open container
A line is not required when taking measurements in an open container since the negative chamber is connected with the
atmosphere.
Ensure that no dirt enters the open connection ports, for example by using connection screws with a 7MF4997-1CP bleed
valve.
+
)XOOVFDOHYDOXH
6WDUWRIVFDOHYDOXH
K
2
K
8
Measurement assembly on an open container
Formula:
Start of scale value: p
MA
= ρ · g · h
U
Full-scale value: p
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