CiDRA Sonar Process Monitoring System - Manual (Page 18)

rating of the enclosure. Refer to paragraph 8.3.1 for information on
the selection of cable glands.
7.3 Installation Site Ambient Temperature, Pressure,
Humidity
7.3.1 Temperature
The transmitter (TB8-xx-xx-xx-03 or TB8-xx-xx-xx-04) must be
installed in a location where the ambient temperature during operation
will be within -20 ºC to +57 ºC.
The sensor head (SH-xxx-xx-xA-xxx-03) must be installed in a location
where the ambient temperature during operation will be within -40 ºC
to +60 ºC.
The process temperature of the fluid in the pipe on which the sensor
head is mounted must stay within -40 ºC to +100 ºC during operation.
The cable used to connect the transmitter to the sensor head must
have a temperature rating consistent with the ambient temperatures
along the path over which it is routed. Cable installers should observe
the cable’s minimum installation temperature rating.
7.3.2 Barometric Pressure
The range of ambient air pressure over which validity of the Zone 2
certification of equipment so marked applies is 80 to 110 kPa (0.8 to
1.1 bar) (11.76 to 16.17 PSIA). This ambient air pressure range
translates into an altitude range of approximately +1950 meters to
-700 meters (+6400 feet to -2300 feet).
The safety standards assume the air in the vicinity of this equipment
has normal oxygen content, typically 21% by volume. If nearby
sources of excess oxygen are present, please consult with CiDRA
Customer Support prior to installation.
7.3.3 Humidity
The sonar process monitoring system certification is based on
Pollution Degree 2. This means the electrical circuitry inside the
enclosures is expected to be exposed to only dry non-conductive
pollution that will only temporarily become conductive due to
condensation.
The IP55 enclosures are suitable for installation outdoors where there
can be wide fluctuations in temperature and moisture levels in the
environment.
Condensation on circuit boards should be avoided. In the continuous-
operating mode of operation for which this equipment was designed,
the heat generated on those circuit boards will help keep them free of
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