M&C TechGroup PMA 50 EEX Operator's manual User Manual
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Gas sampling and gas conditioning technology
9-3.15-ME
Every operational control is accessable from outside and guarantees a simple an d user-friendly
handling during calibration and change-over of the measuring range.
The operational controls are:
Adjustment of measuring range span value 10,
Range switch 11 and
Adjustment zero point 12.
The oxygen display of the PMA 50 Ex is effected by a two-scale analogue instrument 2, with
ranges of 0-30 Vol% and 0-100 Vol % O
2
. A digital display 3 is integrated into the analogue dis-
play. Here, the oxygen value is indicated in a range of 0-100Vol% with a resolution of 0,1Vol%.
The change-over of the measuring range is to be done via the range switch 11. The measuring
range chosen is displayed by a respective LED 13 on the front plate of the PMA 50 Ex and via a
potential free contact (see Fig. 5) to external.
The selection of the measuring range can also be effected externally. The LED 14 on the front
plate of the analyser signals the remote measuring range control in connection with a respective
measuring range LED.
The functioning of the analyser heating is indicated by the flashing LED 5.
The PMA 50 Ex has got a collective status output as standard. This is a potential-free change-
over contact in ‘Safety-First’ switching. The breaking capacity is 200mA with 48V DC or 2A with
250V AC. The state is displayed via status-LED 4. The following status signals are given:
Light source defective,
measuring cell not coupled,
flow failure <5 / >80Nl/h,
power supply error control,
mains voltage breakdown,
transmitter temperature <+45°C / >+60°C,
failure measuring range selection
11.1
PMA 50 EX/P/PD-1-50 WITH PRESSURE COMPENSATION AND ENCLO-
SURE PURGING (WITHOUT SIL-CERTIFICATION)
In case of barometric or process originated pressure variations, the PMA 50 Ex can be equipped
with a special pressure compensation. The compensation can be effected within a pressure
range of 0,6
– 1,5 bar abs.. Thereby errors in measurement caused by pressure variations can
be eliminated.
Additionally the analyser is equipped with an enclosure purging via ventilate arrestors in the inlet
and outlet. The enclosure purging is necessary in case of corrosive sample gas and / or pressure
above 1,1 bar abs.. In case of a leackage in the analyser pressure can not be built up and in case
of additionally corrosive sample gas the analyser will not be damaged. The necessary purge gas
quantity is 10
– 60 Nl/hr corresponding to the adjusted sample gas quantity and the purge gas
inlet pressure is max. 100 mbar.
N O T E !
The enclosure purging has to flow off atmospherically free!