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ZIROX Sensoren & Elektronik GmbH 

Am Koppelberg 21, D-17489 Greifswald 

+49 3834 8309 -00, Fax: -29 E-mail: [email protected] 

 

 

 

ZIROX Oxygen Measuring Systems 

 

SGM7 

 

OXYGEN MEASURING DEVICE 

for the determination of oxygen concentrations 

in inert and reactive gases 

 

MANUAL 

 

Power supply: 100…240 V, 47…63 Hz

Содержание SGM7

Страница 1: ...rg 21 D 17489 Greifswald 49 3834 8309 00 Fax 29 E mail info zirox de ZIROX Oxygen Measuring Systems SGM7 OXYGEN MEASURING DEVICE for the determination of oxygen concentrations in inert and reactive ga...

Страница 2: ......

Страница 3: ...Composition of the oxygen monitor SGM7 14 6 1 General composition 14 6 1 1 General overview 14 6 1 2 Construction principle of the solid electrolyte sensor 15 6 1 3 Electronic data processing 16 6 2...

Страница 4: ...ctrolyte sensors for the optimal running of combustion processes 31 10 2 Potentiometric ZrO2 cells for the measurement of the H2O H2 ratio 35 10 3 Installation instructions for Swagelok fittings 37 10...

Страница 5: ...of making technical improvements the user is responsible for inserting the additional or updated pages supplied Proper operation of the SGM7 can only be ensured if the contents of this manual are kno...

Страница 6: ...danger The degree of the damage depends on the circumstances and the actions of the persons involved In case of disregard destruction or damage of the SGM7 its single components or other material asse...

Страница 7: ...duction as well as plant construction production processes of electronic components under buffer gas The introduction of explosive gas compounds high concentrations of halogens or sulphuric gases e g...

Страница 8: ...operation only see chapter 2 The SGM7 is to be installed operated and serviced by trained staff only The SGM7 is to be connected to an isolated ground socket Schuko socket with the supplied cable Expl...

Страница 9: ...oxygen at the reference electrode in dry air in Pa pO2 meas gas partial pressure of the oxygen at the measuring electrode in the measuring gas in Pa The sensor of the SGM7 is based on the conductivit...

Страница 10: ...ntration is valid for measuring gases with free oxygen as well as for reducing gas compounds in which oxygen only exists in bound form e g in H2 H2O or CO CO2 compounds 1 Different conditions of oxyge...

Страница 11: ...gas inlet tube has no leaks or permeability For measurements of oxygen concentrations less than 10 ppm the following aspects must be taken into account during evaluation composition of the measuring...

Страница 12: ...emp of the gas 80 C p over measuring cell Approx 1 kPa 100 mm WS at 10 l h Working conditions 10 45 C rH 80 at 20 C Storage conditions 20 60 C rH 95 at 20 C Degree of protection IP40 5 2 Mechanical da...

Страница 13: ...ell temperature too low Error3 Thermocouple defective Error6 System error Analog output Current signal 0 4 20 mA potential free range adjustable apparent Ohmic resistance max 500 Ohm Alternative volta...

Страница 14: ...n of the SGM7 is shown in fig 1 Fig 1 General composition of the SGM7 The measuring gas gets into the sensor by means of little overpressure at the inlet or the optional pump ingests the measuring gas...

Страница 15: ...yte measuring cell Measuring cell sensor In order to gain a higher oxide ion conductivity of the zirconium dioxide tube the sensor is heated to 750 C This also avoids interfering reactions with combus...

Страница 16: ...ing block diagram illustrates the data processing Sensor Amplifier for Cell Voltage Heater Control Microcontroller Sensor Surveillance Pow er Supply 1 0 A 0 8 A Amplifier for Thermocouple Display Keyb...

Страница 17: ...the front of the SGM7 Depending on the size the measured values are displayed either in vol or in vol ppm from 1 in vol below that in vol ppm A green or orange light serves as operating indication de...

Страница 18: ...M7_eng docx 18 6 2 3 Rear The gas inlet and outlet the analog output the RS232 interface and the power switch are located on the rear panel The line cord is permanently fixed with the device It cannot...

Страница 19: ...from cold surroundings to a site with higher ambient temperature or humidity A waiting time of about 2 hours before switching on must be considered 1 Install the SGM7 in the favored place see chapter...

Страница 20: ...e g Novodirekt Kehl Oxygen concentration of 100 ppm Stainless steel tube Silicone can cause measuring inaccuracies because of its oxygen permeability Therefore the manufacturer advises against a usage...

Страница 21: ...the chosen dimension 8 1 2 Gas flow adjustment For exact measurings a flow rate of 5 to 10 l h has to be ensured For measurings via bypass the flow rate is realized by an internal pump For excess pre...

Страница 22: ...Self check of the SGM7 Chart 4 Status error messages Status Display Remark 0 OK 1 LIMIT Alarm relay active 2 RANGE Alarm relay inactive 3 RANGE 4 FLOW 5 l h 5 FLOW 10 l h 6 7 8 9 WARM UP Cell temperat...

Страница 23: ...vol or 0 1 210000 ppm For optimal resolution in a certain range Max measuring value 21 0 vol or 210000 ppm higher values on request This value corresponds to the terminal value of the analog signal e...

Страница 24: ...inally confirmed with the key A Main display OXYGEN Flow rate 20 64vol WARM UP Status line PUMP OFF 650 C Pump state on off by key and cell temperature The following status can be visualised by LED re...

Страница 25: ...V or 2 10V ZERO POINT 0 ppm END MARK 206400 ppm AVERAGE FACTOR 1 sec 1 99 sec RETURN B 4 Calibration CALIBRATION CALIBR ZERO POINT CALIBR SPAN GAS RETURN B 4 1 Calibration zero point CALIBR ZERO POINT...

Страница 26: ...S VALUE 206400 ppm Current measuring value SPAN GAS 1000 ppm Adjustable CALIBR SPAN WAIT 5 Calibration status CALIBR VALUE 1 00 Calibration value 2 RETURN 2 If this line is activated and key Enter is...

Страница 27: ...g ENTER After approx 5 sec the calibration is finished Leave the calibration by pressing RETURN and ENTER Save it with YES 8 3 2 Span gas calibration Certified test gas oxygen concentration near futur...

Страница 28: ...suring value although a low value for the oxygen concentration is expected Gas flow too low Increase flow rate Micro leaks in gas supply Check fittings Measurement is dependent on the flow rate the sm...

Страница 29: ...cturer for an overhaul If not in use the SGM7 has to be stored in the original packing if possible in a dry dust free room storage 9 2 Replacement of the equipment fuse Turn the SGM7 off and separate...

Страница 30: ...HB_SGM7_eng docx 30...

Страница 31: ...chemical thermodynamic and electrochemical fundamentals which the application of potentiometric solid electrolyte sensors i e galvanic solid electrolyte cells in the running of combustion processes is...

Страница 32: ...h burn contain the carbon hydrogen ratio in the hydrocarbon V 2 n m and the thermodynamic equilibrium constants of the reactions CO2 CO 1 2 O2 lg KC 4 505 14700 K T H2O H2 1 2 O2 lg KH 2 947 13008 K T...

Страница 33: ...drogen If two oxygen electrodes are exposed to different oxygen concentrations on opposite sides of a gastight sintered ZrO2 solid electrolyte the electrode exposed to the higher oxygen concentration...

Страница 34: ...tandard potentials do not drop out when the cell voltage equation is derived In this case a NERNST equation is obtained for reaction cells with concentration independent terms e g cells with hydrogen...

Страница 35: ...H2 exp 1290 6 U mV 0 0431 T K 7 5732 2 Different conditions of oxygen in the measuring gas must be distinguished Free oxygen Oxygen molecules in the gas are independent without a bond to other gas co...

Страница 36: ...rogen in the measuring gas e g 7 vol The ZIROX device e g SGM displays the H2O H2 ratio of 3 3 x 10 4 From this it follows a H2O concentration of 0 00231 vol or 23 1 ppm 1 ppm is 10 4 vol You must cal...

Страница 37: ...Oxygen Monitor SGM7 10 Appendix HB_SGM7_eng docx 37 10 3 Installation instructions for Swagelok fittings...

Страница 38: ...lcohols are adsorbed by the carbon After longer usage the cell voltage or the oxygen concentration can drop unexpectedly This is a sign for saturation of the filter The filter or the carbon filling mu...

Страница 39: ...hnical data Weight Approx 285 g Volume Approx 100 ml Duration of operation Depending on the components and the concentration of the adsorbed organic components e g approx 1 3 months at raw gas from a...

Страница 40: ...Oxygen Monitor SGM7 10 Appendix HB_SGM7_eng docx 40 10 5 EU Declaration of conformity...

Страница 41: ...s not permitted either A connection of ZIROX and non ZIROX products voids any warranty claims Warranty and warranty claims are only accepted if they are in accordance with the General Sales and Delive...

Страница 42: ...HB_SGM7_eng docx 42...

Страница 43: ...Oxygen Monitor SGM7 11 Your notes HB_SGM7_eng docx 43 11 Your own notes and remarks...

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