PI17xx
Electronic pressure sensor
14
5.3 Ventilation diaphragm
5.3.1 Function ventilation diaphragm
The ventilation diaphragm enables the relative pressure measurement since barometric and
temperature-dependent pressure fluctuations between the measuring cell and the environment are
compensated for.
The ventilation diaphragm is protected against damage by a screwed filter cover with circumferential
ports.
For a correct functioning of the ventilation diaphragm please take the following into account:
u
Remove soiling and cleaning agents immediately using plenty of lime-deficient splash water.
If the sensor is in a cooling stage:
u
Avoid contact of the ventilation diaphragm with liquids to avoid negative pressure in the
measuring system (resulting in a slightly falsified measured value) and additional strain on
the diaphragm.
5.3.2 Orientation filter cover
Select the installation situation so that the filter cover is horizontal and the condensate can drain off
due to gravity.
3
1
2
u
Ideal orientation (1):
The filter cover is in a horizontal position.
w
The ventilation diaphragm (2) in the filter cover is in a vertical
position.
u
Maximum inclination of the filter cover: 30° (3)
5.3.3 Replace filter cover
(1) Exchange of the filter cover incl. ventilation diaphragm (E30483).
In difficult environmental conditions or an installation situation that does not correspond to the ideal
alignment (1), the following accessories can be used to protect the ventilation diaphragm:
(2) Replace the filter cover with a closed version (E30148)*.
(3) Replace the filter cover with a version with a tube fitting and a vent tube that ends in a protected and dry area (E30139).
(4) Set of accessories (E30467) with integrated replacement diaphragm (ventilation diaphragm). Recommended for chemically
demanding applications in external cleaning. Function: (
Ò
Installation instructions E30467).
