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VZOR will appreciate any suggestions and comments aimed at product quality improvement. If you have any trouble with the instrument performance, please contact us in writing or by phone. Postal address: 603106, Russia, Nizhny Novgorod, POB 253 Telephone: + 7 (831) 229-65-67, 412-29-40 E-mail: market@vzor.nnov.ru...
C O N T E N T S 1 DESCRIPTION AND OPERATION ............... 4 1.1 Purpose ......................4 1.2 Basic parameters ..................... 4 1.3 Specifications ....................6 1.4 Product components ..................7 1.5 Description and operation ................7 1.6 Measuring instruments, tools and accessories ..........9 2 INTENDED USE ....................
1 DESCRIPTION AND OPERATION 1.1 Purpose 1.1.1 Product name and designation MARK-302Т dissolved oxygen analyzer TU 4215-022-39232169-2008. 1.1.2 The analyzer has been designed to measure the dissolved oxygen concentration and water temperature. 1.1.3 The analyzer’s scope of application is high-sensitivity measurement of the mass concentration of dissolved oxygen (in the microgram range).
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1.2.5 Analyzed water parameters: temperature, °С ………………………………………………….…... 0 to +50; pressure, MPa, max ……...………………………………..….……..… 0.05; salt content, g/dm ……...………………………..………..……..…... 0 to 40; рН ……………………………………………………….…….…..4 to 12; rate of water flow via flowing vat, cm /min ....…………….
1.3 Specifications 1.3.1 DOC (dissolved oxygen concentration) measuring range at an analyte temperature of 20 °С, mg/dm ..………………………………….……..….. 0 to 10,00. The upper limits of DOC measuring range, depending on the analyte tem- perature, are shown in Table 1.2. Table 1.2 t, °C DOC, 17,45 15,29 13,48 12,10 10,00 9,85 8,98 8,30 7,69 7,12 6,59...
1.3.13 Analyzer oscillatory readings in DOC measurement for 8 h, mg/dm max ……………………………………………………………..….….. ±(0,0015+0,02C). 1.4 Product components The analyzer comprises: converter unit; oxygen sensor with a 2 m connecting cable; flowing vat. 1.5 Description and operation 1.5.1 General analyzer data The MARK-302Т...
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DOC in the analyte. The analyzer features a temperature sensor (platinum thermal resistor) to measure temperature and to automatically compensate for the temperature de- pendence of the oxygen sensor signal. The temperature sensor signal is supplied to the ADC input. The ADC converts signals of the oxygen sensor and the temperature sensor into codes incoming the microcontroller.
Flow measurements use flowing vat 6. Fig.1.1b shows the oxygen sensor design. The sensor’s basic functional elements are platinum cathode 7 and silver anode 8. Secured to cathode 7 with caprone thread 9 is teflon film 10. The mem- brane and rubber bushing form membrane assembly 11 fitted over bushing 12 and filled with electrolyte 13.
2 INTENDED USE 2.1 Operating limitations 2.1.1 2.1.1 The MARK-302Т analyzer version is primarily used to measure DOC in deaerated water. 2.1.2 2.1.2 Para.1.2.5 provides permissible concentrations for a number of components which affect measuring results. 2.1.3 2.1.3 The analyzer should be positioned so as to prevent water from getting on the converter unit.
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2.3.1 Power supply connection To connect the power supply, remove the battery compartment cover located on the rear panel of the converter unit. Install two AA-type alkaline batteries ob- serving the polarity marking inside the battery compartment. Replace the battery compartment cover.
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analyzer precalibration by atmospheric air oxygen; check of readings in the null solution. It is recommended that the analyzer functional check be performed: after filling the sensor with electrolyte on delivery of the analyzer; after replacement of the membrane assembly or teflon film; ...
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With the above procedure successfully completed, the analyzer is ready for normal service. The analyzer calibration by outside air shall then be performed as per para.2.3.4. If the readings do not decrease to the specified level, a sensor cycling opera- tion should be carried out as per para.2.3.3.3.
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switched on. Submerge the sensor fully in distilled water of room temperature for a minimum of 10 min. Rinse the sensor in distilled water, shake off water drops from the sensor membrane and put the sensor in the cone flask with a water layer 3 to 5 mm, as shown in Fig.2.1.
Proceeds as follows prior to carrying out this operation: switch on the analyzer; prepare a fresh null solution as per para.2.3.3.2; enable the DOC measuring mode in mg/dm perform cycling operations as per para.2.3.3.3; hold the sensor in the air for 5 min, submerge the sensor, with its mem- brane down, in the null solution and move it to slightly agitate the solution in order to prevent air bubbles from amassing on the membrane;...
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Cable bushing Outlet connection Protective bushing Drainage From sampler Inlet connection а Fig. 2.2 2.4.1.1 Measurement using a flowing vat Connect the inlet connection of the flowing vat (with the sensor installed) to the controlled water line with a flexible hose. Supply controlled water to the flowing vat and position the vessel with sensor so that the sensor is nearly vertical, its membrane down.
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Measurements may dispense with the flowing vat, if the sensor is placed in a suitable vessel ensuring a controlled water flow of 5 cm/s in the sensor membrane area. To protect the membrane from damage, it is recommended to screw in the protective bushing.
2.4.3 Calculation of dissolved oxygen concentration by analyzer readings, with allowance for the salt content When measuring DOC in salty water, use the correction factor α, by which the analyzer readings should be multiplied. The α value is defined with the formula: ...
when outside air calibration is accomplished, (para.2.3.4) neither Е3 nor Е4 is displayed on the screen and readings C , mg/dm , are set with an accuracy ±1 % of the calculated value defined with the formula: Р С ...
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Table 2.2 (Continue) Trouble, symptoms Probable cause Remedy 4 When the analyzer is cal- Electrolyte has leaked Para.2.6.3. Fill in electro- ibrated by outside air, Е3 lyte (sensor current below rat- Contaminated mem- Para.2.6.2. Clean ing) is displayed. brane membrane Dry membrane Keep the membrane in water for 2-3 days with-...
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Тable 2.2 (Continue) Trouble, symptoms Probable cause Remedy 9 During measurements, Operator’s errors in an- Para.2.6.6. Perform op- indication of exceeded dis- alyzer calibrations erations to set initial ana- play digit capacity appears lyzer parameters on the screen: Broken down analyzer Factory repair “Е6 mg/dm ”...
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Cable bushing Case Syringe Bushing filled with Capron thread electrolyte Teflon film Membrane assembly Membrane а Remove Protective bushing Remove Fig. 2.3 − Dismantling the sensor for filling and replacement of electrolyte, replacement of teflon film and membrane assembly IMPORTANT: The membrane should be stretched and pressed firmly against the sensor platinum cathode.
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Remove the membrane assembly from bushing 6, drain the remaining elec- trolyte and wash the assembly with distilled water. Fill the membrane assembly with new electrolyte. Electrolyte composition: KCl, chemically pure – 14 g; KOH, chemically pure – 0.2 g; versene – 0.15 g; distilled water – up to 0.1 dm .
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2.6.5 Platinum electrode cleaning A need for platinum electrode cleaning in a special solution arises in 6-12 months after the first use. It is not recommended to clean the electrode before this period expires. To clean the electrode, prepare two solutions. Solution composition: ...
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2.6.6.1 Zero shift setting 1 Switch off the analyzer. 2 Press the CAL button and, keeping it pressed, switch on the analyzer. Af- ter a sound signal release the CAL button. The screen will display с2. 3 Press the ENTER button. The donЕ capture will briefly appear on the screen and the analyzer will go into the measurement mode.
3 MAINTENANCE Maintenance of the analyzer comprises: analyzer calibration by outside air (para.2.3.4) to be carried out every 8 hours; analyzer zero calibration (para.2.3.5) to be carried out every three months; sensor cycling (para.2.3.3.3) to be carried out when the analyzer has not been in use for more than 24 hours.
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