M&C TechGroup PMA 50 EEX Operator's manual
Operating Manual
Oxygen Analyser Series PMA
Version PMA 50 Ex
Gas sampling and gas conditioning technology 9-3.15-ME
2
This Operating Manual does not claim completeness and may be
subject to technical modifications.
© 04/1996 M&C TechGroup Germany GmbH. Reproduction of this
document or its content is not allowed without permission from M&C.
PMA® is a registered trade mark.
6th Edition: 12/2011
Dear customer,
we have made up this operating manual in such a way that all necessary information about the
product can be found and understood quickly and easily.
Should you still have any question, please do not hesitate to contact M&C directly or go through
your appointed dealer. Respective contact addresses are to be found in the annexe to this operating manual.
Please also contact our homepage www.mc-techgroup.com for further information about our
products. There, you can read or download the data sheets and operating manuals of all M&C
products as well as further information in German, English and French.
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List of Contents
1 General information ......................................................................................................... 5
2 Declaration of conformity ................................................................................................ 5
3 Electrical standards ......................................................................................................... 6
4 Safety instructions ........................................................................................................... 6
5 Information and safety instructions for using the Analyser in hazardous areas ......... 7
6 Warranty ........................................................................................................................... 7
7 Used terms and signal indications .................................................................................. 8
8 Introduction ...................................................................................................................... 9
8.1 Serial number ............................................................................................................... 9
8.2 Power supply ................................................................................................................ 9
9 Application ....................................................................................................................... 9
10 Technical Data ................................................................................................................ 10
10.1 Options ....................................................................................................................... 11
11 Description ..................................................................................................................... 12
11.1 PMA 50 Ex/P/PD-1-50 with pressure compensation and enclosure purging (without
SIL-certification) .......................................................................................................... 13
11.2 PMA 50 Ex/P/PD with pressure compensation (without SIL-certification) .................... 14
11.3 Option zero suppression (without SIL-certification) ..................................................... 14
11.4 Option enclosure purging or ventilation ....................................................................... 14
12 Measuring principle ....................................................................................................... 15
13 Gas flow diagram ........................................................................................................... 16
14 Receipt of goods ............................................................................................................ 18
15 Installation ...................................................................................................................... 18
16 Supply connections ....................................................................................................... 19
16.1 Sample gas inlet and sample gas outlet ...................................................................... 19
16.2 Option purging enclosure or ventilation ....................................................................... 19
16.3 Electrical connection ................................................................................................... 20
17 Starting up ...................................................................................................................... 21
18 Calibration ...................................................................................................................... 21
18.1 Zero calibration ........................................................................................................... 22
18.2 Span calibration .......................................................................................................... 23
19 Measuring ....................................................................................................................... 25
20 Cross sensitivities ......................................................................................................... 26
21 Closing down .................................................................................................................. 29
22 Storage and Transport ................................................................................................... 29
23 Maintenance ................................................................................................................... 29
23.1 Removal of the measuring cell .................................................................................... 30
23.2 Mechanical zero point adjustment ............................................................................... 33
24 Spare parts list ............................................................................................................... 34
25 Appendix......................................................................................................................... 35
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List of Illustrations
Figure 1 PMA 50 Ex Oxygen Analyser ................................................................................. 12
Figure 2 Scheme of the measuring cell and optical signal processing .................................. 15
Figure 3 Gas flow diagram ................................................................................................... 16
Figure 4 Gas conditioning .................................................................................................... 17
Figure 5 Electrical connection in the connection box of the PMA 50EX EEX e ..................... 20
Figure 6 Schematic view of the internal layout of the analyser ............................................. 30
Figure 7 Transmitter unit ........................................................................................................ 32
Figure 8 Schematic view of the transmitter unit .................................................................... 33
Figure 9 Circuit diagram front board PMA50ex 10.2008 ....................................................... 38
Figure 10 Assembly front board PMA50ex 10.2008 ............................................................... 39
Figure 11 Circuit diagram mains adapter PMA50ex 10.2008 .................................................. 40
Figure 12 Assembly / connection mains adapter PMA 50ex 10.2008 ..................................... 41
Figure 13 Cut-out magnification front board for adjustment of temperature alarm (TP10,
P19) (TP11: actual temperature) und flow alarm threshold (P20) ............................ 42
Figure 14 Cut-out magnification front board couple sensor bridge for application of a
transmitter without couple sensor ........................................................................... 42
Figure 15 Cut-out magnification front board for adjustment of reference voltage ,
amplification and offset of the O2-signal .................................................................. 43
Figure 16 Cut-out magnification mains adapter for adjustment of the temperature, current
and voltage output .................................................................................................. 44
Figure 17 Cut-out magnification mains adapter for adjustment of burden and limitation of
the current output ................................................................................................... 44
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Head Office
M&C TechGroup Germany GmbH Rehhecke 79 40885 Ratingen Germany
Telephone: 02102 / 935 - 0
Fax: 02102 / 935 - 111
E - mail: info@mc-techgroup.com
www.mc-techgroup.com
1 GENERAL INFORMATION
The product described in this operating manual has been examined before delivery and left our
works in perfect condition related to safety regulations. In order to keep this condition and to
guarantee a safe operation, it is important to heed the notes and prescriptions made in this operating manual. Furthermore, attention must be paid to appropriate transportation, correct storage,
as well as professional installation and maintenance work.
All necessary information a skilled staff will need for appropriate use of this product are given in
this operating manual.
2 DECLARATION OF CONFORMITY
CE - Certification
The product described in this operating manual complies with the following EC directives:
ATEX-Directive
The product described in this manual is produced in accordance with the EC directive for devices and
protection systems for appropriate use in hazardous areas 94/9/EG appendix II.
EMV-Instruction
The requirements of the EC directive 2004/108/EG “Electromagnetic compatibility“ are met.
Low Voltage Directive
The requirement of the EC directive 2006/95/EG “Low Voltage Directive“ are met.
Declaration of conformity
The EU Declaration of conformity can be downloaded from the M&C homepage or directly requested from M&C.
The SIL –declaration of conformity can be requested directly at M&C.
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3 ELECTRICAL STANDARDS
The electrical standard of electrical equipment corresponds to the safety regulations concerning
the EN61010 and to the safety requirements of the European standards EN 61508; EN 50014 :
1997, EN 50018 : 2000, EN 50019 : 2000, EN 50020 : 2002 and EN 50284 : 1999 for operation of
the equipment in hazardous areas group II category 2. Attention must be paid to the Certificate of
Conformity KEMA 03 ATEX 2215X (see appendix).
4 SAFETY INSTRUCTIONS
Please note the following basic safety procedures when using this equipment:
Read these operating instructions carefully before start-up and use of the equipment! The
information and warnings given in these operating instructions must be heeded.
Attention must be paid to the requirements of the certificate of conformity (see appendix):
KEMA 03 ATEX 2215X.
Work on electrical equipment is only to be carried out by trained specialists as per the
regulations currently in force.
Attention must be paid to the requirements of VDE 0100 when setting high-power electri-
cal units with nominal voltages of up to 1000V, together with the associated standards
and stipulations.
For use in hazardous area observe the relevant national and international instructions and
regulations.
Check the details on the type plate to ensure that the equipment is connected up to the
correct mains voltage.
Protection against touching dangerously high electrical voltages. Before opening the
equipment, it must be switched and hold no voltages. This also applies to any external
control circuits that are connected.
The equipment is only to be set within the permitted range of temperatures and pres-
sures.
Check that the location is weather-protected. It should not be subjected to either direct
rain or moisture.
Installation, maintenance, monitoring and any repairs may only be done by authorised
personnel with respect to the relevant stipulations.
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5 INFORMATION AND SAFETY INSTRUCTIONS FOR USING THE ANALYSER
IN HAZARDOUS AREAS
The Oxygen Analyser PMA 50 Ex is suitable for use in hazardous area group II category 2.
The explosion proof protection is:
II 2G EEx de IIC T5 or II 1/2 G EEx de [ia] IIC T5 KEMA (appr.-no.: 03 ATEX 2215X)
The analyser has been certified through KEMA, authorized company for official approval of electric
equipment in the Netherlands. Detailed information and a copy of the certificate are attached to this
operating manual.
Installation and operation of the analyser has to be done corresponding to the conditions in the Excertificate (see appendix). Only in this case, the reliability of operation in hazardous area can be guaranteed.
All changes of the standard analyser with parts which are not specified or approved by M&C as well as
repair and service with not specified parts mean a loss of the Ex-certificate.
In case of doubt, please turn directly to M&C respectively to your M&C franchised dealer.
6 WARRANTY
If the equipment fails, please contact M&C directly or else go through your M&C authorised
dealer.
We offer a one year warranty as of the day of delivery as per our normal terms and conditions of
sale, and assuming technically correct operation of the unit. Consumables are hereby excluded.
The terms of the warranty cover repair at the factory at no cost or the replacement at no cost of
the equipment free ex user location. Reshipments must be se nd in a sufficient and proper p rote ctive packaging.
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DANGER!
This means that death, severe physical injuries and/or important material
damages will occur in case the respective safety measures are not fulfilled.
W ARN I NG !
This means that death, severe physical injuries and/or important material damages may occur in case the respective safety measures
are not fulfilled.
CARE!
This means that minor physical injuries may occur in case the respective safety measures are not fulfilled.
CA R E!
Without the warning triangle means that a material damage may occur in case the respective safety measures are not met.
AT T ENT ION !
This means that an unintentional situation or an unintentional status
may occur in case the respective note is not respected.
NOTE!
These are important information about the product or parts of the
operating manual which require user’s attention.
SKILLED STAFF
These are persons with necessary qualification who are familiar with
installation, use and maintenance of the product.
NOTE!
These are important information about the product or parts of the
instruction manual referring to operating in hazardous areas.
7 USED TERMS AND SIGNAL INDICATIONS
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8 INTRODUCTION
8.1 SERIAL NUMBER
The type plate with the serial number is fixed on the left side of the analyser’s housing.
Please indicate always this serial number in case of questions or when purchasing spare parts.
8.2 POWER SUPPLY
The internal power supply of the Oxygen Analyser PMA 50 Ex is reversible 115/230V AC, with
40Hz to 60Hz. Exact indications are to be found on the type plate. Variations of the power supply
of -15% to +10% do not effect the function of the analyser.
9 APPLICATION
The Oxygen Analyser PMA 50 Ex is suitable for the continuous measurement of oxygen in particle-free and dry sample gases with a maximum dew point of 5°C.
The features of the anaylser are safe operation, accuracy and low maintenance.
The measurement is based on the physical principle of the magneto-dynamic oxygen measuring
cell and is one of the most exact quantitative methods of oxygen determination within the range
of 0-100 Vol.% oxygen.
There is a direct flow against the measuring cell which has got a low volume of only 2 ml (small
stagnant volume). Further characteristics are robustness, extremely small drift, fast response
time (T90 < 5 sec.) and negligible cross sensitivities to other sample gas components.
Flow variations within a range of 0 Nl/h to 60 Nl/h air result in a changement of the oxygen indication which is smaller than 0,2 Vol % O2.
Measurements in flue gases and in inerting installments are some typical applications for the
PMA 50 Ex within a great variety of other measurement tasks.
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10 TECHNICAL DATA
Part Number
05A1000 :
05A1000a :
05A2500 :
05A2500a
05A2505 :
05A2505a :
PMA 50 EX, power supply 230V
PMA 50 EX, power supply 115V
PMA 50 EX/P/PD-1-50, power 230V, (not with SIL-certification)
pressure compensation 0,6 - 1,5 bar abs. with purging the enclosure via
two certified ventilate arrestors in the in- and outlet NPT1/4“i
PMA 50 EX/P/PD-1-50, power 115V, (not with SIL-certification)
pressure compensation 0,6 - 1,5 bar abs. with purging the enclosure via
two certified ventilate arrestors in the in- and outlet NPT1/4“i
PMA 50 EX/P/PD, power 230V, (not with SIL-certification)
pressure compensation 0,6 - 1,1 bar abs.
PMA 50 EX/P/PD, power 115V, (not with SIL-certification)
pressure compensation 0,6 - 1,1 bar abs.
Power supply
230VAC (standard) or 115VAC (a) -15% to +10%, 40-60Hz, 35,5VA
Electrical connections
via EEx e connection box 3x PG-cable gland
cable diameter : 6mm - 13mm (M20x1,5), 10mm - 17mm (M25x1,5)
terminals 2,5mm2,
(power, signals, range position and remote choice, status signal)
Measuring ranges
selectable for 0-1, 0-3, 0-10, 0-30 and 0-100 vol.% O2 linear
choice via rotary selection switch at PMA 50 or remote switching
External range indication
Potential free contact for all measuring ranges.
Capacity 48V DC 200mA DC,
Minimum contact rating 5V/1mA
Remote range selection
Measuring ranges selectable via potential free contacts max. 30V DC
3mA DC. The function is displayed at the PMA 50 via LED.
Combined analogue/digital indicator
analogue meter with a scale of 0-30 and 0-100% for each selected range
digital meter 4 1/2 digit 9 mm high LCD-indicator for 0-100% O2 reading,
selectivity 0,01vol.% O2
Output signals
0/4-20mA burden 270 Ω for every measuring range, electrically isolated;
output voltage max. 15V (ex works).
Switchable max. burden 800 Ω, output voltage max. 30V.
Output current limiting adjustable 20mA-22mA (20,5mA ex works)
0-10V DC, burden >100 KΩ for range 0-100 % isolated.
Response time for 90% FSD
< 5 seconds at 60 Nl/hr air
Accuracy after calibration
1% of the span value of measuring range after calibration or 0,02%O
2
depending on which value is the higher one
Reproducibility
Analogue output = < 1% of measuring range / digital indication =
± 0,01 Vol.% O2
Influence of ambient temperature
No influence up to 50 °C
Influence of barometric pressure
The oxygen reading varies in direct proportion to changes of the barometric pressure.
No influence from 0,6-1,5 bar abs. at PMA 50 EEX/P/PD-1-50 with
process pressure compensation
Influence of sample gas flow
Variation in gas flow between 0-60 Nl/hr air will cause a difference of
< 0,2 vol.% O2
Sample gas inlet pressure
0,01-0,1 bar g standard or in case of purging up to 0,5 bar g
(PMA 50 EEX required admission pressure for competent flow rate, no
pump inside)
Sample gas outlet pressure
outlet of analyser must discharge freely into atmosphere
or 0,6-1,5 bar abs. at version PMA 50 EEX/P/PD-1-50 with process pressure compensation
Flow rate of sample gas
Min. 10 Nl/hr up to max. 60 Nl/hr adjustable externally via flow meter (no
flowmeter inside)
Temperature of sample gas
-10 °C up to +50 °C dry gas
O2-transmitter temperature
fixed at +55 °C
10
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Temperature cutoff
at 72°C via thermal fuse, non-reversible
Ambient temperature
During operation between -10° C to + 50° C
Storage temperature
-20°C to +60°C at relative air moisture of 0-90% r.h.
Medium touched material
Platine, glass, PTFE, PVDF, stainl. steel 1.4571, Epoxy
Connections measuring gas
Ventilate arrestors at inlet and outlet, NPT 1/4" i
Flow failure
thermo-conductive flow sensor downstream mounted after measuring cell
Status signal outlet
Change-over contact, switching capacity 250 V AC 2A AC, 48V DC
200mA DC minimum contact rating 50mW for temperature <+45°C /
>+60°C, defect light beam, measuring cell not coupled, flow failure
<5 / >80Nl/h, power supply error control, mains voltage breakdown,
failure measuring range selection
Housing / colour
EEX-d e wall mounted explosion-proof housing / blue
Dimensions/Weight
475 (535mm with ventilate arrestors) x 355mm x 200mm (HxWxD) / 22kg
Classification/Protection
II 2G EEx de IIC T5 or II 1/2 G EEx de [ia] IIC T5
IP54 DIN 60529
Certificate No.
KEMA 03 ATEX 2215X
Part
number
Options
05A9015
Zero suppression in range of 1%-97%; Only in connection with part no. 05A2500(a)
PMA50EEx/P/PD-1/50. Externally switchable via potential free contacts, 30V DC 3mA DC
(not with SIL-certification)
05A9005
Extra charge for one ventilate arrestor for PMA-50Ex... for pressure range up to 1500mbar abs.
and non-corrosive gases, connection NPT1/4"i.
05A9000
purging the enclosure via two certified ventilate arrestors, for pressures up to max. 1,5 bar abs.
and/or corrosive gases, connection 1/4" NPTi, purge gas inlet pressure max. 100 mbar, flow
rate 10-60 Nl/hr
Transmitter for measurements of gases from ex-zone 0 II 1/2 G EEx de [ia] IIC T5
90A0009
Measuring cell type PMC-1LB, solvent resistant.
90A0006
Measuring cell PMC-1G with glass solder. O-ring made of Chemraz
10.1 OPTIONS
11
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130
70
60
200
355
520
2
3
4
571
6
8
9
10
111213
141516
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.% O2.
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 temperature 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 elements 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.
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.
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NOTE!
The enclosure purging has to flow off atmospherically free!
Every operational control is accessable from outside and guarantees a simple and 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 % O2. A digital display 3 is integrated into the analogue display. 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 ENCLOSURE 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.
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NOTE!
For excess pressure operation (>100 mbar) an enclosure ventilation according to the ex-certificate is necessary. For additionally corrosive
sample gas an enclosure purging is necessary. Both have to flow off
atmospherically free!
11.2 PMA 50 EX/P/PD WITH PRESSURE COMPENSATION (WITHOUT SILCERTIFICATION)
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 – 1,1 bar abs.. Thereby errors in measurement caused by pressure variations can
be eliminated.
11.3 OPTION ZERO SUPPRESSION (WITHOUT SIL-CE RTIFICATION)
A zero suppression is possible for devices with pressure compensation within a range of 1% to
97% O2. The suppressed measuring range depending on the suppression is lying on the position
of a standard measuring range. The factory provided adjusted suppression can be switched on
and off via an actuator at the terminals 22 resp. 23 inside of the connection box of the analyser
(see Fig. 5). After switching off the original measuring range again is active.
11.4 OPTION ENCLOSURE PURGING OR VENTILATION
For measurement of corrosive gases it is recommandable to equip the analyser with an enclosure
purging. This reduces the risk of a destruction of the analyser by corrosion in case of leaky gas
ways. For this please choose option part number 05A9000 ( 2 x ventilate arrestors). 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.
In case of elevated inlet pressure of 1,1bar up to max. 1,5bar abs. also one ventilate arrestor
according to the ex-certificate (see appendix) is required. For this choose option with part number
05A9005. For elevated inlet pressure of 1,1bar up to max. 1,5bar abs. and corrosive sample gas
the analyser has to be equipped with option part number 05A90000 (enclosure purging). 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.
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2 4 3
1
GAS INLET
GAS OUTLET
12 MEASURING PRINCIPLE
Oxygen is a gas with a significant paramagnetic susceptibility. The molecules of oxygen are attracted much more strongly by a magnetic field than the molecules of other gases.
The measuring principle shown in the following is benefitting from these characteristics of the
oxygen. The great advantage of the paramagnetic measuring principle is the highly reduced cross
sensitivity of the measurement to other components in the sample gas.
Figure 2 shows the diagram of the measuring cell as well as the optical system for the detection
of the dumbbell’s movement.
Figure 2 Scheme of the measuring cell and optical signal processing
The measuring cell consists of two nitrogen-filled spheres which are arranged in the form of a
dumbbell. In the dumbbell’s central point of rotation, a small mirror is placed. The dumbbell is
surrounded by a wire coil needed for the compensation procedure. The described system is fixed
rotationally symmetrical inside a glass tube via a tightening strap out of platinum and is srewed
up with two pole pieces .
Two permanent magnets are producing an inhomogeneous magnetic field. When oxygen is flowing in, the molecues of the oxygen are drawn into the magnetic field. In consequence, the lines of
electric flux on the cuneiform pole pieces are compressed. The nitrogen-filled diamagnetic
sheres are pushed out of the magnetic field. This causes a rotation of the dumbbell. The rotation
is detected via an optical system consisting of mirror , projection LED and photoelectric cell
.
In case the dumbbell is pushed out of the magnetic fieild, the tension of the photoelectric cell is
immediately changed. The measuring amplifiers and are producing a respective current
which develops via the wire coil on the dumbbell an electro-magnetic load moment. The load
moment is resetting the dumbbell into its zero position.
Gas sampling and gas conditioning technology 9-3.15-ME
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