ZIRON Oxygen Measuring Technique. Oxygen Measuring Device ECO1000. Manual

Transcription

1 ZIRON Oxygen Measuring Technique Oxygen Measuring Device ECO1000 Manual Sales and Service Center Shanghai ZIRON Gasanalyzer Co., Ltd 404/6, No.10, Lanxi Road, Shanghai P.R. China Tel , Fax ,

2 ZIRON Oxygen Measuring Device ECO Table of contents 1 The Company ZIRON... Fehler! Textmarke nicht definiert. 1.1 Business development... Fehler! Textmarke nicht definiert. 1.2 Cooperations... Fehler! Textmarke nicht definiert. 2 General Manual hints Copyright Safety symbols and terms Safety regulations Applications of the ECO General properties Functional description, construction and operation Measuring principle Construction principle of the solid electrolyte measuring cell Electronics Further annotations to the ECO Measuring cell Why calibration? Measuring gas containing organic compounds? Charcoalfilter use! Technical data Installation und initiation Mechanical assembly Power supply Front Rear Operation and calibration General Calibration Zero gas calibration (Offset compensation) Span gas calibration Adjustment span gas concentration Menu navigation Trouble shooting, maintanance and storage Error messages Trouble shooting Appendix Warranty conditions Charcoal filter: Description and application hints...18

3 ZIRON Oxygen Measuring Device ECO Filter construction Filter function and use Charcoal changing Technical data Declaration of conformity...20

4 ZIRON Oxygen Measuring Device ECO General 1.1 Manual hints This operation manual describes design, function and operation of the oxygen measuring device ECO1000. Sales and Service Center Sinom Corp. No.33, Sec.4, Jhongsing Rd., Wugu, New Taipei,Taiwan Tel Fax sales@sinom.com.tw Internet: The manufacturer assures that this operation manual has been written in accordance with the functional and technical features of the delivered ECO1000. This operation manual is not subject to the amendment service. If the manufacturer modifies the ECO1000 with the aim of making technical improvements the user is responsible to insert the additional or updated pages supplied. Secure and proper function of the ECO1000 can only be guaranteed when the contents of this manual are known. Therefore, all chapters of this manual must be read carefully before installation and operation of the ECO1000. The display values shown in this manual are samples or presettings of the manufacturer. The process specific values must be set by user. 1.2 Copyright This manual is copyright protected. It must not be reproduced partially or totally, copied or distributed, without prior written admission from the manufacturer, neither unauthorized use for the purposes of competition or the handing over of the manual to third parties are permitted. All rights reserved.

5 ZIRON Oxygen Measuring Device ECO Safety symbols and terms Symbol for direct imminent hazards This symbol is shown with recommendations for industrial safety if a direct danger exists to the life and health of persons. If these recommendations are not thoroughly observed, fatal injuries may result. Symbol for indirect imminent hazards This symbol informs about situations where indirect hazards occur. Degree and intensity of the damage depend on the triggering actions and the behavior of the persons involved. Disregard of these hints may result in damage to or destruction of the entire ECO1000 or single components, other property, as well as minor injuries. Symbol for proper usage This symbol is found where the observance of instructions, regulations, and proper order of actions/events is important. Not observing these hints may result in damage or destruction of the ECO1000 or its single components. 1.4 Safety regulations The following regulations for industrial safety give basic information about possible hazards during handling and operation of the ECO1000. Therefore, they must be observed and strictly followed by operation and service staff. Secure and proper function of the ECO1000 can only be guaranteed when the contents of this manual are known. Therefore, all chapters of this manual must be read carefully before installation and operation of the ECO1000. The ECO1000 may be used for applications stated as authorized only (see chapter 2). The ECO1000 may only be installed, operated, and maintained by trained staff. In any case, the ECO1000 must be connected to the main supply with a socket with earth connection by supplied cable. Explosive gas mixtures, halogens in high concentration, gas mixtures containing silicon, phosphor and sulfur (e.g. SO 2 ) are not permitted to be measured by ECO1000.

6 ZIRON Oxygen Measuring Device ECO Due to the high operation temperature of the sensor, the ECO1000 produces much heat. It has to take care that the ECO1000 is not covered so strongly that it will be come to overheatings. Vertical installation is not permitted to avoid possible damages to the device by localization of heat. Switch off and disconnect the device from the power supply before opening the housing cover! Special safety recommendations for possible hazards during special work or sequences of work are given in the relevant text. The measuring gas can be reducible for a short time 1 (the electronics show 0). It must not be an explosive mixture the heating of the measuring cell is an ignition source. For measurements in corrosive gases, if condensates or carbon deposition are possible, a consultation by manufacturer is strongly recommended. 1.5 Applications of the ECO1000 In many technological processes the presence of oxygen traces is harmful to the product properties. The rapid and accurate measurement of oxygen traces in the process atmosphere is prerequisite for the identification and prevention of problems. With the ECO1000 the oxygen concentration of a sample is measured and displayed continuously, as well as variations of adjustable setpoints is signalized. With the increasing introduction of quality management systems (eg ISO 9000) the monitoring and documentation of relevant quality parameters are necessary. By ECO1000 the user receives a variety of possibilities for process optimization and quality control. The main areas of the device are monitoring functions in the welding and soldering technology (eg. reflow soldering with inert gas). In this case an charcoal filter must be used. With the help of the filter hydrocarbons, which give a measuring error, are restrained. 1 It has to be distinguished between different conditions of the oxygen in the measuring gas: Free oxygen: There are the oxygen molecules in the gas independently without every relationship relation to the other gas components (inert gases such as N 2 or Ar) Bound oxygen: There aren't any free oxygen molecules, but only in bound form e.g. as steam in the gas. At higher temperatures dissociation is carried out and oxygen molecules then are availably. Since the dissociation degree increases with the temperature, the measurement result is also dependent on the temperature. Circumstances permitting free oxygen can react with perhaps available burning gasses at the hot platinum electrode, a reducing gas then can be also in the result through what.

7 ZIRON Oxygen Measuring Device ECO General properties The compact oxygen measuring device contains a zirconia measuring cell, a measuring gas pump and the electronics. The sensor element is heated by internal heater control. A microprocessor calculates the oxygen concentration according to the NERNST law. The measuring value is shown on the display and given out by analog (4-20 ma) and digital interface (option). Software for data processing is available (option). A span gas calibration can be made by certified test gas. If requested the internal pump can be switched off.

8 ZIRON Oxygen Measuring Device ECO Functional description, construction and operation 2.1 Measuring principle The NERNST-equation is used as basis for determining the oxygen concentration in gases with the ECO1000 NERNSTequation Dabei ist: U F p O 2,air RT U = ln zf p Cell voltage in mv p O 2, Air O 2, measuringgas R Molar gas constant, R = 8,314 J/(mol K) T Measuring temperature in K p O 2,measuring gas Faraday-constant, F = 9, C/mol Oxygen partial pressure at reference electrode in dry air in Pa Oxygen partial pressure at measuring electrode in Pa 2.2 Construction principle of the solid electrolyte measuring cell (I) The sensor of the ECO1000 is based on the conductivity of oxide ions in a special ceramic substance (zirconia) with stabilising additives. The conductivity of these oxide ions increases exponentially with the temperature and it is sufficiently high for temperatures above 600 C. The gas to be measured passes through the ceramic oxide ion conductor which is a gas-tight pipe. The ceramic pipe is situated axial-symmetrically in a thermic well-insulated heater. The electrodes of the galvanic sensor are made from platinum. The electrode on the outside of the pipe, surrounded by dry air, is used as a reference electrode with a constant, known electrode potential. Measuring cell The ECO1000 is not explosion-proof! 2.3 Electronics The electronics serve the power supply of the measuring cell, calculation of the oxygen concentration from measuring value and output as standard signal (4-20 ma). Additionally a span gas calibration can be made. The electronics realize following functions: Power supply of the measuring cell and heating control Cell and thermo voltage processing to oxygen concentration Oxygen concentration output via standard signal Calibration Measuring gas suction by internal pump

9 ZIRON Oxygen Measuring Device ECO Further annotations to the ECO Measuring cell Due to physical-chemical basics the cell voltage depends on the oxygen concentration. Therefore it does not change with increasing age. Only the inner resistance of the cell increases with time, depending on environmental conditions. This means that the accurate measurement of cell voltage during the aging process is more complicated. The limit of the inner resistance of the cells is approximately kohm and after the experience from Germany this value will be reached after 3-5-years at normal stress (no catalyst poisons or pollutants in the exhaust gas). For devices, which came back for calibration after one year, the inner resistance were 100 to 200 ohms. According to the NERNST law the calculation of oxygen occurs from the voltage of the cell and its temperature. The measuring value is determined thermodynamically if the measuring electrode is not damaged, the cell voltage reflects the concentration of oxygen concentration accurately Why calibration? Cause for the calibration is the thermo couple type K. It can not be integrated in the electrode. Therefore a manufacturing temperature offset between electrode and temperature measurement occurs. This offset can be compensated by calibration. The thermo couple type K ages. A drift of the thermo voltage occurs over the years. The measured temperature (with type K) can more than 10 C deviate from the real electrode temperature. Only by calibration with test gas this error can be corrected and the oxygen calculation readjusted respectively. This type of measuring cell is more cost-saving at manufacturing (low-cost wires, base metal materials) than cells with thermo couple type B or S Measuring gas containing organic compounds? Charcoalfilter use! If the measuring gas contains reducing components (e.g. alcohol or solvent vapour) the concentration of free oxygen cannot be determined correctly because chemical reactions occur at the electrode. In such cases the measuring gas should be filtered by a charcoal filter (see chapter 8). After longer action the filter could be saturated if the oxygen concentration drops suddenly. In this case the whole filter cartridge or the charcoal must be change (see chapter 8).

10 ZIRON Oxygen Measuring Device ECO Technical data Range Vol.-ppm, till 100 Vol.-% on request Accuracy... rel. error < 5% Gas flow l/h (by internal pump) Max. measuring gas pressure mbar over pressure Max. measuring gas temperature C at gas input Dimensions (B x H x T) mm x 123 mm x 235 mm Mass... 3kg Protection degree... IP 20 Gas input... Screw connection for hose 6 x 4 mm Gas output... Hose nipple 4 mm Working conditions C, rel. humidity < 80% at 20 C Storage conditions C, rel. humidity < 95% at 20 C Power supply V AC, Hz (at 110 V AC the pump performance drops strongly) Power consumption VA max. Heating measuring cell V DC, ca. 10 W (controlled internally) Fan V DC, A Keyboard... keypad with 2 keys Clear text display... Double-spaced LCD-Display, 2 x 16 characters Digital interface... RS232 (Option) Analog output... 0/4 20 ma, potential-free, Zero point and endmark free scalable ppm, resistance max. 500 Ohm Option: Voltage output... 0/2 10 V, potential-free, Zero point and endmark free scalable ppm Limit value... < ppm Fuse... 2 x 1 A/T Terminal strip Analog output PIN Designation 1 -I out 2 +I out 3 Alarm 4 Alarm

11 ZIRON Oxygen Measuring Device ECO Installation und initiation 4.1 Mechanical assembly All components are located (main electronics, pump, line filter, measuring cell) in a portable housing. 4.2 Power supply The ECO1000 is connected by rubber connector and delivered cable. It is a portable device. The working position is horizontally. 4.3 Front On the front display and keys are located. Operation and parameterization hints follow in chapter 6. The lateral charcoal filter is installed firmly (Option). Fig. 1: Front view of ECO1000

12 ZIRON Oxygen Measuring Device ECO Rear Gas in- and output, fan, Sub-D-socket for RS232 and rubber connector witch power switch are located on the rear of ECO1000. If a charcoal filter is mounted (Option), the gas input is on the filter! Fig. 2: Rear view of ECO1000 The measuring values and the status messages can be transmitted via RS232 and analog output. Interfaces

13 ZIRON Oxygen Measuring Device ECO Operation and calibration 5.1 General After switching on the warm up starts. Over 400 C the temperature is displayed additionally in the second space. If the measuring cell temperature has reached 750 C the oxygen concentration is also displayed. Warm up: approx. 15 minutes With pressing the cell voltage is displayed in the second space. With help of the booth keys an offset-calibration ( zero point calibration ) in ambient air and a span gas calibration are possible. The whole menu is shown in figure 3, page 16. ***WARM UP*** Temp: 555 C O2: 20.6 Vol.-% Uz: xx.x mv Calibration 5.2 Calibration Especially before measurements with high accuracy request a calibration should be taken (The stability of measuring cell and electronics is so high that a check is only necessary once a year). The device must be in the operation state at least 1 hour before calibration. A calibration in the lower range (< 10 ppm O 2 ) makes sense only without charcoal filter! With filter it can not be measured in this range! 5.3 Zero gas calibration (Offset compensation) This check is very important if the measuring value will be near 20 percent of oxygen. The heater can be changed by small mechanical instabilities or aging. The result is a small temperature deviation at the electrodes and therefore a small cell voltage changing. This missing voltage is compensated by zero gas calibration. For zero gas calibration ambient air must flow through the measuring cell by the expected measuring gas velocity. This status is reached by internal pump. The zero gas calibration is described in chapter 6.6.

14 ZIRON Oxygen Measuring Device ECO Span gas calibration For the span gas calibration a certified test gas with the expected measuring gas concentration flows through the measuring cell (connection via bypass the flow is realized by internal pump). Adjustment of the span gas concentration and the calibration procedure is shown in chapter 6.5 and Adjustment span gas concentration After call SPAN GAS Concentration at calibration menu (see figure 3) the adjustment possibility is activated by. The blinking character can be adjusted by. After changing of all characters this menu is deactivated by and leaved by. Now the calibration can be started.

15 ZIRON Oxygen Measuring Device ECO Menu navigation Fig. 3: Navigation overview

16 ZIRON Oxygen Measuring Device ECO Trouble shooting, maintanance and storage 6.1 Error messages During working process a monitoring of the measuring cell occurs continuously for the identification of typical errors. Error message on display SYSTEM ERROR LOW PROBE TEMP. ERROR THERMOCOUPLE Description During system start the self-test has found a system error. The soll-temperature (750 C) is not reached. Thermo couple or cable are broken. 6.2 Trouble shooting Error message SYSTEM ERROR ERROR THERMOCOUPLE Display does not shine During span gas calibration: CALIBR. FAILED Cause and clearance Please contact manufacturer! Check contacts and connections of the thermo couple, check thermo voltage ATTENTION: Authorized Stuff only! Check power supply Test gas does not correspond to the adjusted span gas concentration. The calibration factor is out of values given by manufacturer. Test gas or adjusted span gas concentration must be checked resp. readjusted. After longer action the filter could be saturated if the oxygen concentration drops suddenly. In this case the whole filter cartridge or the charcoal must be change (see chapter 8). A charcoal filter changing is recommended after 600 operation hours!

17 ZIRON Oxygen Measuring Device ECO Appendix 7.1 Warranty conditions ZIROX warrants that the equipment manufactured and sold by it will be free of defects in workmanship or material upon delivery. Should any failure corresponding to this warranty conditions become apparent during a period of 12 months (sensor) or 24 months (electronic) after the date of delivery, ZIROX will correct such nonconformity by repair or replacement of the defect parts after prompt written notice from the purchaser. The purchaser is not entitled to claim any other legal remedies on the basis of this warranty. ZIROX does not warrant equipment supplied by it against normal deterioration (e.g. reference gas pump). Corrosive gases and solid particles may cause damages and make a repair or a replacement necessary as a consequence of normal wear and tear during the warranty period. The contact of the products with explosive gas mixtures, halogens in high concentrations and sulphur-containing gases (e.g. SO 2 ) is not permissible. The contact of the products with silicon- or phosphor-containing compounds is also not permissible. In the case of combination of ZIROX products with non- ZIROX products, which are not approved by ZIROX, any warranty claim is invalid. Warranty and warranty claims are only accepted if they are in accordance with the "General Sales and Delivery Conditions" of the manufacturer. Warranty and liability claims for injuries to person and/or property damages are void if the claims are due to one or more of the following causes: normal wear unauthorized using disregard of the regulations of the equipment manual improper installation, operation, and maintenance operation of the device without electrical protection (i.e. proper ground connection) unauthorized functional or technical modifications removal of parts or installation of spare parts or additional units which are not delivered or permitted by ZIROX improperly executed repairs or wrong handling Stranger influence and superior force Attention: When installing the equipment, the customer must ensure that all necessary supply lines are connected and the operating temperature of the probe is reached. Experience has shown that products installed but not taken into operation may be damaged by the process or by external influence. ZIROX will not accept any responsibility for such damages.

18 ZIRON Oxygen Measuring Device ECO Charcoal filter: Description and application hints Filter construction The figure above shows the charcoal filter. Two caps with tube connections close the charcoal acryl glass container. Both caps have been passed into the tube (sealed by O-ring). The fittings (tube connection with seal ring) have closing stopper against falling out of the charcoal. For the gas way protection against charcoal particles a prefilter and a fine filter (2 filter paper discs) have been installed into the output of the charcoal filter Filter function and use Organic components of the measuring gas (e.g. alcohols) will be adsorbed by the charcoal. After longer using the cell voltage or the oxygen concentration can be drop unexpectedly. This is a sign for saturation of the filter. The filter or the charcoal filling must be changed Charcoal changing A saturated filter can be recycled by changing of the activated carbon filling only. For this purpose the charcoal must be poured out after removing the tubes (press black part into the connection and pull out the tube) and the tube connection at gas input (wrench size 11). Then new granulated charcoal can be refilled into the container by a small funnel. The powder should be compressed by knocking a piece of wood against the filter housing. Finally, the removed tube connection with seal rings must be screwed onto the filter again. For a connection ECO1000 charcoal filter the tube must be only inserted into the tube connection.

19 ZIRON Oxygen Measuring Device ECO Caution: Do not remove the closing stopper in the Plug connections! Technical data Dimensions (diameter x length) Weight Volume Duration of Use Used charcoal 33 mm x 165 mm approx. 200 g Approx. 100 ml Depending on the components and the concentration of the adsorbed organic components e.g. approx. 1 3 months at raw gas from a fermenting tank (ZKG) granulated or pelleted, 1 3mm

20 ZIRON Oxygen Measuring Device ECO Declaration of conformity