Siemens MS Series, Instruction Manual, Page: 102 / 130

SITRANS P, MS series
102
C79000-B5674-C40-04
Installation
5.1 Where to Install
The transmitter can be installed above or below the pressure tapping point.
When measuring gases we recommend the transmitter to be installed above the
pressure tapping point and the pressure pipe to be laid so that it runs down to the
pressure tapping point. This will permit any condensation in the pipe to drain off and
not affect the measurement (recommended arrangement, see Chapter 6.1, p. 110).
When measuring vapor and liquids the transmitter should be installed below the
pressure tapping point and the pipe laid so that it rises up to the pressure tap, thus
enabling any gas to be dispersed through the main pipe (recommended arrange-
ment, see Chapter 6.2, p. 111).
The point of installation should be easily accessible, preferably close to the measur-
ing point and free from vibration. The permitted ambient temperature limits must not
WARNING
Devices
with the protection type "flameproof enclosure" may only be opened when
the power is off.
Notes on operation of the intrinsically-safe version in hazardous areas:
Operation is only permitted on circuits which are certified as intrinsically safe.
The transmitter is compliant with Category 1 / 2 and may be installed at zone 0.
The EU type examination certificate applies for installation in the walls of con-
tainers and pipes which may contain explosive gas/air or vapor/air mixtures only
under atmospheric conditions (pressure 0.8 bar to 1.1 bar, temperatur -20 °C to
+60 °C). The permissible ambient temperature range is -40 °C to +85 °C, in
explosion hazard areas -40 °C to m85 °C (T4).
The user max also apply the device in non-atmospheric conditions outside the
limits set in the EC-Type Examination Certificate, according to the conditions for
use (explosive mixture) and if the required additional security measures have
been met. The limit values stated in the general technical data must be observed
in any cases.
Additional requirements are necessitated in the case of instalation at zone 0:
The installation must be adequately sealed (IP67 to EN 60 529). An industrial
standard (e.g. DIN, NPT) threaded joint is suitable for example.
When operating with intrinsically safe power supply units of the "ia" category, the
explosion protection does not depend on the chemical resistance of the seal
diaphragm.
When operation with intrinsically safe power supply units of the "ib" category or
for units with explosion proof type of protection "Ex d" and simultaneous use at
zone 0, the explision protection of the transmitter depends on chemical resis-
tance of the diaphragm. Under these operating conditions, the transmitter max
only be used for those imflammable gases and liquids to which the diaphragms
are adequately chemically resistant to avoid corrosion.