6. Commissioning, operation
Humidity can affect the operating characteristics of
electronic components and sensors, thus a good
positioning prevents problems and extends the
service life. Electronic components and sensors can
be adversely affected due to temperature changes in
combination with condensing humidity (e.g. in evapo-
rators with de-icing systems).
Although the ingress protection of the pressure
transmitter is IP 67 or IP 6K9K, this is not hermetically
sealed. Under critical conditions, there is the danger
that small air volumes can penetrate or diffuse
through the case. Thus, over time, humidity can
collect in the sensor and cause measuring errors.
It is therefore recommended that the pressure trans-
mitter is placed in a location with low humidity and
temperature fluctuations. For chill cabinets or cold
rooms, this place is on the inlet pipe on the outside of
the main cooling chamber, e.g. below the chill cabinet
where the piping comes out of the chill cabinet.
If positioning is required closer to the evaporator, it is
recommended that a capillary is used between the
evaporator outlet line and the pressure transmitter.
WIKA operating instructions pressure transmitter, model R-1
Fig.: Pressure transmitter with capillary
(exterior view)
Fig.: Pressure transmitter with capillary
(cross-section)
EN
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