M&C TechGroup PMA 50 EEX Operator's manual - Manual (Page 12)

12
Gas sampling and gas conditioning technology 9-3.15-ME
11 DESCRIPTION
The main part of the PMA 50 Ex is the magneto-dynamic oxygen measuring cell.
This measuring principle is one of the most precise quantitative methods for determination of the
oxygen contents in the range of 0-100 Vol.% O
2
.
The Oxygen Analyser PMA 50 Ex is destined for stationary operation. The mounting into a EEx
de IIC T5 housing 1 with ventilate arrestors in the sample gas inlet and outlet 6 makes it possible
to install the analyser in hazardous area of group II category 2. Equipment with protection (s. type
plate)
II 1/2 G EEx de [ia] IIC T5 (option) is suitable to measure explosive gases of group II
category 1.
The analyser is thermostated and regulated to a transmitter temperature of +55°C. The temper a-
ture controller is built in that way that the low-voltage part is separated from the 230V capacity
part via an optoelectronic coupler with no-voltage releasing magnet.
A fast and homogeneous conduction of temperature is guaranteed by large-surface heating ele-
ments mounted on the transmitter surface.
An overheating of the transmitter to more than 72°C is avoided by a non-reversible thermal fuse.
The transmitter is equipped with an isolating cap in order to accumulate the heat and isolate the
transmitter.
Figure 1 shows the Oxygen Analyser PMA 50 Ex in front view and side view.
130
70
60
200 355
520
2
3
4
5
7
1
6
8 9
10
11
12
13
14
15
16
Figure 1 PMA 50 Ex Oxygen Analyser
A window in the housing of the analyser enables you to control the indications of the measured
value 2, the status LEDs 4 and 5 as well as the measuring range LEDs 13 and 14.