Measuring Cell For Level - Siemens SITRANS P DS III Operating Instructions Manual

3.6.3.3

Measuring cell for level

①
②
③
④
⑤
Figure 3-9
● The inlet pressure (hydrostatic pressure) works hydraulically on the measuring cell
● Differential pressure at the measuring cell is transmitted to the differential pressure
● When measuring limits are exceeded, the overload diaphragm
● The seal diaphragm
● The change in the resistance causes a bridge output voltage proportional to the
SITRANS P DS III with HART
Operating Instructions, 06/2013, A5E00047092-09
Pressure cap
O-ring
Measuring cell body
Overload diaphragm
Differential pressure sensor
Function chart of the measuring cell for level
through the seal diaphragm
⑤
sensor through the seal diaphragms
⑥
the seal diaphragms
⑥ thus protect the differential pressure sensor
⑥
changes the resistance of the four doped piezoresistors in the bridge circuit.
differential pressure.
⑥
Seal diaphragm on the measuring cell
⑦
Filling liquid of the measuring cell
⑧
Capillary tube with the fill fluid of the mounting
flange
⑨
Flange with a tube
⑩
Seal diaphragm on the mounting flange
⑩
on the mounting flange
⑥
and the filling liquid
⑩
or rests on the measuring cell body
is displaced by the differential pressure. The displacement
3.6 Functional principle
⑩
.
⑦
.
④
is displaced until one of
③
. The seal diaphragms
⑤
from overload.
Description
29