M&C TechGroup PMA 50 EEX Operator's manual - Manual (Page 21)

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Gas sampling and gas conditioning technology 9-3.15-ME
17 STARTING UP
The following steps have to be executed when starting up the analyser:

Before starting the equipment for the first time, check that the electrical connections and the
gas connections have been executed as requested. The voltage indicated on the type plate
must correspond to the mains supply.

Any zero point deviation of the analogue display can be set right via the adjusting screw below
the digital dispay. For this purpose, the housing of the analyzer must be opened in a voltage -
free status.

Set the range switch to 30% and switch on the analyser by using the main switch. No w, the
display of the analyser shows an oxygen value of less than 21% with ambient air.

The warming up status is displayed by the permanently beaming temperature control LED on
the front plate (figure 1). After approximately 30 minutes, the PMA 50 Ex has reached its op-
erating temperature. This is signalized by the flashing of the temperature control LED.
N O T E !
The temperature is stable after approx. 3 hours. Now, the analyser can be
calibrated according to the following instructions. For controlling the
stable status, a further calibration should be effected after 24 hours !
18 CALIBRATION
Before executing the calibration, the safety instructions relating to the instalment and the process
must be heeded !
The precision of the measurement depends on the precision of the analysers calibration.
The linearity of the measuring ranges allows a two-point calibration, the zero calibration and the
span calibration.
A weekly calibration of the analyser guarantees the required precision of the measurements.
Due to the direct proportional dependance of the oxygen indication to the barometric respectively
process pressure, the calibration interval may be decreased to on e day in case there are great
variations of pessure.
N O T E !
In principle, a calibration should be effected under measuring conditions,
holding the flow quantities, the room temperature and the barometric
pressure to a constant value. Avoid vibrations!