Installing Transmitter; Mounting; Remark; Pay Attention To Ventilation - Dräger PEX 3000 Gebrauchsanweisung

Installing Transmitter

Installing Transmitter
The transmitter PEX 3000 is EMC class A equipment. The transmitter may cause
radio interferences in living areas. In this case, the operator may request
appropriate measures to be taken.

Mounting

Orientation: The transmitter must be mounted such that the sensor's gas entrance
area of the sensor is pointing downwards. If to be mounted at the ceiling a
mounting bracket must be used.
— Install transmitter in vertical position at a location with little vibration and
maximum temperature stability (no direct sun light) in the vicinity of a possible
leak.
— Consider the complete scope of environmental conditions influencing the
transmitter. Avoid external influences such as splashing water, oil, corrosive
aerosols (salt mist) etc. and the possibility of mechanical damage.
— Leave at least 30 cm free space beneath the transmitter to provide accessibility
for calibration work.

Remark

Certain substances in the atmosphere to be monitored may impair the sensitivity of
the sensors (DrägerSensor PR M DD or LC M) installed in the transmitter:
The following substances are known at present:
a) polymerizing substances such as acrylo nitrile, butadiene and styrene,
b) corrosive compounds such as ammonia and halogenated hydrocarbons
(releasing halogenes such as bromine, chlorine or fluorine when being oxidised),
c) catalyst poisons such as sulphurous and phosphorous compounds, silicon
compounds, and metal-organic vapours.
The sensors used are based on measuring elements (pellistors) which are poison-
resistant and so have a longer lifetime than conventional sensors if catalyst poisons
occur. However there is still the rule to shorten the test or calibration intervals if
catalyst poisons are expected to occur in the atmosphere to be monitored.

Pay attention to ventilation!

— Always arrange sensing head and transmitter in air flow between possible leak
or collection point and possible source of ignition.

Pay attention to the density of gas!

— In case of gases, the density of which is lower than that of air, such as hydrogen,
methane or ammonia the transmitter or sensing head must be located above a
possible leak or at the highest points at which major concentrations of gas may
be found.
— In case of gases and vapours with a density greater than that of air, the sensing
head or transmitter must be installed beneath a possible leak or at the lowest
points at which such gases and vapours may be present.
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NOTICE