wtw PhotoLab S6 Operating Instructions Manual
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wtw PhotoLab S6 Operating Instructions Manual

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Operating Instructions
Part 1:
General Information
Part 2:
Functional Description

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Summary of Contents for wtw PhotoLab S6

  • Page 1 Operating Instructions Part 1: General Information Part 2: Functional Description...

  • Page 3: Table Of Contents

    Contents 1. Photometers ....... . . 1.1 Photometry ........1.2 The Photometers .

  • Page 4: Photometers

    ® Spectroquant Analysis System consists of the following components: The individual components are optimally coordi- nated to be fully compatible with each other and make it possible to conduct state-of-the-art analysis without any further accessories being required (according to GLP* and AQA** requirements). 1.

  • Page 5: The Photometers

    1. Photometers 1.2 The Photometers ® The photometers possess AQA (Analytical Quality The photometers that belong to the Spectroquant Assurance) functions to assure the quality of the Analysis System differ from conventional photo- measurement. meters in the following important aspects: New methods can be downloaded from The calibration functions of all test kits are elec- our homepage www.merck.de and stored...

  • Page 6: Spectroquant Reagent Tests

    2. Photometric Test Kits ® 2.1.2 Spectroquant Reagent Tests The principle behind the reagent tests is that the example, 5 ml of sample. This means that there is no reagents necessary for the colour reaction are com- need to dilute the sample, which in turn enhances the bined in the form of liquid concentrates or solid- sensitivity of the detection.

  • Page 7: Influence Of Ph

    2. Photometric Test Kits 2.2.2 Influence of pH Chemical reactions follow an optimal course only (1 mol/l; raises the pH) dropwise, testing the pH with within a certain pH range. The reagents contained in suitable indicator strips after each drop is added. the test kits produce an adequate buffering of the The addition of the acid or lye results in a dilution of sample solutions and ensure that the pH optimal for...

  • Page 8: Influence Of Foreign Substances

    2. Photometric Test Kits 2.2.5 Influence of Foreign Substances Foreign substances in the sample solution can been determined for the individual ions; they may not be evaluated cumulatively. raise the measurement value as a result of an amplification of the reaction, or Suitability for use in salt water lower the measurement value as a result of a A tabular survey (see pages XVI –...

  • Page 9: Shelf-Life Of The Reagents

    2. Photometric Test Kits 2.2.7 Shelf-life of the Reagents ® The expiry date is printed on the outer label. The The Spectroquant test kits can be kept for up to shelf-life may become shortened when the reagent three years when stored cool and dry. A few tests bottles are not reclosed tightly after use.

  • Page 10: Dilution

    3. Sample Preparation 3.3 Dilution Dilution of samples is necessary for two reasons: All dilutions should be made in such a way that the measurement value lies in the middle of the measur- The concentration of the parameter under investi- ing range.

  • Page 11: Homogenization

    3. Sample Preparation As a measure to distinguish between dissolved and Following the recommendations stated in the refe- undissolved water-borne substances, the water rence methods, membrane filters with a pore size of sample can be filtered through a simple paper filter. 0.45 µm are required for fine filtration.
  • Page 12 3. Sample preparation The manner in which the sample is pretreated en- The decomposition processes are carried out in the ables the three proportions to be distinguished from thermoreactor (capacity: 8 /12 decomposition cells) each other. This can be illustrated using a copper- at 120 °C or, respectively, 100 °C.

  • Page 13: Pipetting System

    4. Pipetting System Positive-displacement pipettes permit Check the pipetted volumes by weighing using analytical scales (weighing accuracy ±1 mg), an exact dosage of the sample volume, and 1 ml of water at 20 °C = 1.000 g ±1 mg. a precise measurement of sample and reagent ®...

  • Page 14: Quality Control For The User

    5. Analytical Quality Assurance (AQA) certificate for the test kit, available for each lot produced, documents the quality of the reagents contained in the test kit. Calibration function: The calculated function must agree, within specified tolerances, with the function electronically stored in the photometer. Confidence interval: Maximum deviation from the desired value over the entire mea- suring range;...

  • Page 15: Checking The Photometer

    5. Analytical Quality Assurance (AQA) 5.2.1 Checking the Photometer As soon as the photometer is activated it is running a the photometer via the bar code, and the measured Self-Check. This means the hardware and the soft- absorbance is compared with the desired value. ware of the photometer is checked and compared The absorbance is shown in the display and can be with internal standards.

  • Page 16: Checking The Pipettes

    5. Analytical Quality Assurance (AQA) 5.2.3 Checking the Pipettes ® of the measurement cell and reference cell may not The Spectroquant PipeCheck is used exceed the tolerances given in the package insert. to check the pipettes. The pack contains If the tolerances are exceeded, the instructions given cells filled with colour-dye concentrates.

  • Page 17: Definition Of Errors

    5. Analytical Quality Assurance (AQA) 5.4 Definition of Errors It is obvious that measurement results as a rule may The following diagram illustrates the aspects of be associated with errors. This applies equally to accuracy and precision: standardized methods of analysis (reference methods) and to routine analysis.
  • Page 18 Suitability of Test Kits for Testing Salt Water Test kit Art. Seawater Limit of tolerance, salts in % NaCl NaNO Alkohol Cell Test 14965 – – – Aluminium Test 14825 Ammonium A5/25 Ammonium Cell Test 14739 Ammonium Cell Test 14558 Ammonium Cell Test 14544 Ammonium Cell Test...
  • Page 19 Suitability of Test Kits for Testing Salt Water Test kit Art. Seawater Limit of tolerance, salts in % NaCl NaNO Nitrate Test 14773 – Nitrate Test 09713 – Nitrate Cell Test (salt water) 14556 – Nitrate Test (salt water) 14942 –...
  • Page 20 ® Spectroquant CombiCheck and Standard Solutions Test kit, Art. CombiCheck, Art. Evalu- Confidence interval Other ation Spec. value for tolerance standards** the standard Art. Alcohol Cell Test, 14965 – 3 g/l ± 0.3 g/l 09008 Aluminium Test, 14825 CombiCheck 40, 14692 0.75 mg/l ±...
  • Page 21 ® Spectroquant CombiCheck and Standard Solutions Test kit, Art. CombiCheck, Art. Evalu- Confidence interval Other ation Spec. value for tolerance standards** the standard Art. Nitrate Cell Test, 14563 CombiCheck 20, 14675 9.0 mg/l ± 0.9 mg/l 19811 Nitrate Cell Test, 14764 CombiCheck 80, 14738 25.0 mg/l ±...
  • Page 22 Instructions for the Preparation of Standard Solutions Standard solution of bromine Standard solution of free chlorine acc. to DIN EN ISO 7393 Preparation of a stock solution of free chlorine: First prepare a 1:10 dilution using a sodium hypo- Preparation of a KlO stock solution: chlorite solution containing approximately 13 % of In a 1000-ml volumetric flask dissolve 1.005 g...
  • Page 23 Instructions for the Preparation of Standard Solutions Standard solution of free chlorine Standard solution of free chlorine acc. to DIN EN ISO 7393 Preparation of a standard solution: Dissolve 1.85 g of dichloroisocyanuric acid, Preparation of a KlO stock solution: sodium salt, GR with DI water in a calibrated or In a 1000-ml volumetric flask dissolve 1.005 g conformity-checked 1-l volumetric flask and make...
  • Page 24 Instructions for the Preparation of Standard Solutions Standard solution of chlorine dioxide Standard solution of formaldehyde acc. to DIN EN ISO 7393 Preparation of a stock solution: In a calibrated or conformity-checked 1-l volu- Preparation of a KlO stock solution: metric flask make up 2.50 ml of formaldehyde In a 1000-ml volumetric flask dissolve 1.005 g solution min.
  • Page 25 Instructions for the Preparation of Standard Solutions Standard solution of COD Standard solution of iodine acc. to DIN EN ISO 7393 Preparation of a standard solution: In a calibrated or conformity-checked 1-l volu- Preparation of a KlO stock solution: metric flask make up 0.850 g of potassium In a 1000-ml volumetric flask dissolve 1.005 g hydrogen phthalate GR volumetric standard to the of KlO...
  • Page 26 Instructions for the Preparation of Standard Solutions Standard solution of ozone Standard solution of total nitrogen acc. to DIN EN ISO 7393 Preparation of a standard solution: Dissolve 5.36 g of glycine GR with DI water in a Preparation of a KlO stock solution: calibrated or conformity-checked 1-l volumetric In a 1000-ml volumetric flask dissolve 1.005 g...
  • Page 27 Instructions for the Preparation of Standard Solutions Standard solution of sulfide Standard solution sulfite Preparation of a stock solution: Preparation of a standard solution: Place 7.2 g of glass-clear, if necessary washed Dissolve 1.57 g of sodium sulfite GR and 0.4 g of crystals of sodium sulfide hydrate approx.
  • Page 28 Instructions for the Preparation of Standard Solutions Standard solution of hydrogen peroxide Preparation of a stock solution: Place 10 ml of Perhydrol 30 % H GR in a calibrated or conformity-checked 100-ml volumetric flask and make up to the mark with DI water.
  • Page 29 Functional description Edition 03/2004 · Order no. BA41107d05...
  • Page 30 General instructions Notes on this operating manual To ensure that you become rapidly acquainted with your photometer, the first chapter contains an overview and a short manual of the meter. The second chapter contains notes for the safe operation of the photometer.
  • Page 31 Contents 1. Overview ......3 Description of the operating elements ..3 Identifying the connectors .
  • Page 32 Contents 8.1.5 Changing the password ... .26 8.1.6 Performing an AQA reset ...26 Photometer monitoring (AQA1) ... .27 8.2.1 Entering PhotoCheck standards .

  • Page 33: Overview

    1. Overview 1.1 Description of the operating elements a Display b Menu call/Enter key c Scroll key d Recess for MemoChip e Absorbance measure- ment key f Concentration measure- ment key g Notch for cell alignment h Round cell shaft i Storage space for anal- ysis regulations (short form)

  • Page 34: Short Manual

    1. Overview 1.3 Short manual The short manual lists all of the steps necessary to determine the concentration of a sample and to activate AQA2 at a glance. 1.3.1 Measuring the concentration – To switch on the photometer, open the cover. The photometer performs a check (Self-Check) of the entire system and then switches automatically to the concentration measuring mode.

  • Page 35: Selecting And Calling Up The Menu Items

    1. Overview 1.4 Selecting and calling up the menu items – To switch on the photometer, open the cover. – Press The following display appears: Example: The documentation menu item is preselected in the setup menu (z). Select a menu item, e. g. meter setup: –...

  • Page 36: Safety

    2. Safety This operating manual contains basic instructions to working with the meter. be followed in the commissioning, operation and main- The operating manual must always be available in the tenance of the meter. Consequently, all responsible vicinity of the meter. personnel must read this operating manual before 2.1 Authorized use The photometer is authorized exclusively for...

  • Page 37: Commissioning

    3. Commissioning The photometer operates at an environmental temper- Before putting the photometer into service, wait until it ature of +5 °C to +40 °C. During transport from cold to has adapted to the new environmental conditions warm surroundings, condensation can form resulting (see also chapter 15 T ECHNICAL in the malfunction of the meter.

  • Page 38: Measuring The Concentration

    4. Measuring the Concentration – Call up the concentration measuring mode by actuating Measuring mode, concentration 4.1 Measuring using cell tests – Insert the round cell with barcode into the round cell shaft until it clicks into place. Align the line mark to the notch of the photometer. The photometer reads the barcode of the round cell and automatically selects the relevant method.

  • Page 39: Measuring Using Tests Without Barcode (Manual Method Selection)

    4. Measuring the Concentration 4.2 Measuring using tests without barcode (manual method selection) When measuring using cell tests without barcode, the method must be selected manually. The last method set up manually appears on the display. – Select the required method with –...

  • Page 40: Measuring The Absorbance/Transmission

    5. Measuring the Absorbance/Transmission 5.1 Switching to the Absorbance/ Transmission measuring mode – Call up the setup measuring mode by actuating – In the setup menu, call up the abs./trm. % submenu Selection of the measuring mode: absorbance transmission 5.2 Measuring the absorbance or transmission –...

  • Page 41: Measuring Using Cell Tests

    5. Measuring the Absorbance/Transmission 5.3 Measuring using cell tests – Insert the round cell with barcode into the round cell shaft until it clicks into place. Align the line mark to the notch of the photometer. The measured value for the wavelength displayed at the top right appears.

  • Page 42: Documentation

    6. Documentation The measured values can be documented as follows: Storage in the measured value memory Output to a connected printer via the serial interface (automatic when a printer is connected) Transmission to a PC for further processing (by using the relevant software, e.g. Multi/ACHATII or – less conveniently –...

  • Page 43: Resetting The Number Of The Measured Value

    6. Documentation 6.1 Resetting the number of the measured value – Call up the no. of meas. value submenu. The numbering of the measured values starts again with 001 (default) Consecutive numbering of the measured values (from 001 to 999) –...
  • Page 44 6. Documentation Selecting "total" Select the output medium: to display to printer/PC (serial interface). – Select the menu item with – Confirm with to start the memory download. Selecting "from date" – Input the date using – Erase the input using –...

  • Page 45: Download Of The Methods List

    6. Documentation Memory download to printer/PC Memory download to the serial interface: Display of the transmitted no. of measured value (continuation display) beginning with the last measured value. – Cancel with Sample printout: 14541 10.02.98 11:56:33 mg/l 14541 10.02.98 11:54:21 mg/l 14729 03.02.98...

  • Page 46: Method Parameters

    7. Method Parameters The following parameters can be set in the method parameters menu: citation unit – To switch on the photometer, open the cover. – Press The following display appears: – Call up the method parameters submenu. – Input the method number –...

  • Page 47: Citation Form

    7. Method Parameters 7.1 Citation form 7.1.1 Changing the citation form Example: Change the citation form from "NH -N" to "NH ". – Call up the citation submenu. The current setting: NH -N (S). – Using , scroll to NH –...

  • Page 48: Performing A Difference Measurement

    7. Method Parameters 7.1.2 Performing a difference measurement Difference measuring is possible for some methods (e.g. Iron II/III, Ca-/Mg Hardness). For more information on this, see part, "Analysis specifications". Example: Determination of iron (II) and iron (III). – Enter method 106 –...
  • Page 49 7. Method Parameters The 1st measured value appears on the display: Σ Fe. After approx. – Remove cell 1 2 s: – Press – Start the 2nd measurement by inserting cell 2. The 2nd measured value appears on the display: After approx.

  • Page 50: Selecting The Unit

    7. Method Parameters 7.2 Selecting the unit The preset unit is "mg/l". It can be changed to "mmol/l". – Call up the unit submenu. The current setting: mg/l (S) mmol/l – Using scroll to – Confirm with mmol/l – Unit (S) is set.

  • Page 51: Analytical Quality Assurance (Aqa)

    8. Analytical Quality Assurance (AQA) Analytical quality assurance (AQA) can be performed The AQA mode must be activated in the photometer. in two steps: In the delivery state it is switched off. The AQA mode is activated: AQA1 – Photometer monitoring by inserting the AQA MemoChip AQA2 –...
  • Page 52 8. Analytical Quality Assurance (AQA) A password request appears: A separate password protects settings of the AQA- configuration against unauthorized access (Changing the password see section 8.1.5). – Input the password with Only numeric characters are allowed. Default: 0000 – Confirm with If the input was incorrect: –...

  • Page 53: Changing Aqa Intervals

    8. Analytical Quality Assurance (AQA) 8.1.3 Changing AQA intervals AQA intervals specify the interval between two AQA After an interval has expired, the following conse- quences become effective: checks. A fixed time interval (n weeks) or a number of measurements (n measurements) can be specified as Warning and loss of AQA identification the interval.
  • Page 54 8. Analytical Quality Assurance (AQA) AQA interval, "n measurements " The AQA interval, n measurements, is only effective if the n measurements setting is active for the AQA mode function. The AQA2 check starts the monitoring for one method at a time. The specified number of measurements applies to: the instrument with AQA1 (total number of measure- ments performed, independent of whether AQA2 is...

  • Page 55: Locking The System

    8. Analytical Quality Assurance (AQA) 8.1.4 Locking the system As a result, a concentration measurement is not The function system locked is effective if, for a moni- possible for this method. tored method, no AQA check was performed, the AQA check “system” has expired. –...

  • Page 56: Changing The Password

    8. Analytical Quality Assurance (AQA) 8.1.5 Changing the password When delivered, the default password is 0000. This password can be changed as follows: – Call up the change password submenu. – Confirm with – Input the required password, e.g. 0100, with –...

  • Page 57: Photometer Monitoring (Aqa1)

    8. Analytical Quality Assurance (AQA) 8.2 Photometer monitoring (AQA1) 8.2.1 Entering PhotoCheck standards ® A Spectroquant PhotoCheck is required to perform the photometer monitoring (AQA1). At least 1 standard must be input. We recom- mend, however, to input all available standards. –...
  • Page 58 8. Analytical Quality Assurance (AQA) Example: 445-1 nm, theoretical value (absorbance) 0.200, admissible tolerance ± 0.020 – Select with – Quit via the menu item, return – Confirm with – Input the theoretical value, 445-1 – Confirm with If the standard is already stored, this value appears on the display.

  • Page 59: Download Of Photocheck Standards

    8. Analytical Quality Assurance (AQA) 8.2.2 Download of PhotoCheck standards – In the PhotoCheck standards submenu, call up the output menu item. Select the output medium: to display to printer/PC (serial interface). – Select with – Confirm with to start the download. Example: Report output AQA check meter AQA1...

  • Page 60: Performing Photometer Monitoring

    8. Analytical Quality Assurance (AQA) 8.2.4 Performing Photometer monitoring Photometer monitoring (AQA1) includes a check of standards. – Press to call up the setup menu Light barriers using the L1/L2 cells (contained – Call up the AQA check submenu ® within the scope of delivery of the Spectroquant –...
  • Page 61 8. Analytical Quality Assurance (AQA) After successful light barrier testing, the PhotoCheck standards (test solutions) are measured. Example: – Insert a cell with the test solution, 445-1. The photometer measures the absorbance of the test solution and compares the result with the value entered.

  • Page 62: Total System Monitoring With Standard Solutions (Aqa2)

    8. Analytical Quality Assurance (AQA) 8.3 Total system monitoring with standard solutions (AQA2) 8.3.1 Entering standards The standards compiled in the table “Spectro- ® quant CombiCheck and standard solutions” (see part "General information") are already stored method-specifically in the photometer. These values can be overwritten.
  • Page 63 8. Analytical Quality Assurance (AQA) Example: Method 14729 with a preset theoretical value of 15.0 mg/l and tolerance of 1.0 mg/l (CombiCheck 80). Change to: theoretical value = 8 mg/l, tolerance = 0.7 mg/l (CombiCheck 20). – Confirm with – Enter the new theoretical value, e.g. 8.0 mg/l, with Values in parentheses indicate the range in which the theoretical value should move.

  • Page 64: Output Of Standards

    8. Analytical Quality Assurance (AQA) 8.3.2 Output of standards The current list of stored standards is output via the RS 232 interface (PC/printer) or via the display. – Select the output submenu – Confirm with Select the output medium: to display to printer/PC (serial interface).

  • Page 65: Erasing Standards

    8. Analytical Quality Assurance (AQA) 8.3.3 Erasing standards Erasing the method-specific standard solutions leads to the change of the measured value identification from AQA2 to AQA1 (with activated AQA mode). – Call up the standard solutions submenu. – Select the menu item, erase with –...
  • Page 66 8. Analytical Quality Assurance (AQA) AQA check OK ..or error message After approx. 2 s: – Repeat the check If the error is repeated, perform troubleshooting of the error. See "Analytical Quality Assurance" in part "General information". The system AQA2 check must be performed separately for each method monitored.

  • Page 67: Correction Functions

    9. Correction functions – To switch on the photometer, open the cover. – Press – In the setup menu, call up the meter setup submenu. The following display appears: – Call up the correction funct. submenu. The following display appears: Select the correction function: blank value turbidity correct.

  • Page 68: Activating The Blank Value Measurement

    9. Correction functions Measuring the concentration with a blank value – Press to call up the concentration measuring mode. The value measured against the prepared blank solu- tion is displayed. 9.1.1 Activating the blank value measurement – In the correction funct. menu, call up the blank value submenu.

  • Page 69: Measuring The Blank Value

    9. Correction functions 9.1.2 Measuring the blank value – Call up the meas. blank value menu item. The menu items, erase blank value and recall blank values first appear after at least one blank value has been measured. – Insert a cell with blank solution to start a measure- ment.

  • Page 70: Recalling Blank Values

    9. Correction functions – Select the erase blank value menu item – After confirming with the erase blank value menu opens. The erase blank value menu item first appears after a blank value has been measured. Select between Erase all stored blank values single Erase individual stored blank value Each stored blank value is displayed with the...

  • Page 71: Turbidity Correction

    9. Correction functions 9.2 Turbidity correction Turbidity correction is used in sample solutions that The turbidity correct. function is not active when deliv- contain finely distributed suspended particles. The ered. suspended particles cause a light absorption. This leads to incorrect (too high) measured values. This function is not necessary, or useful, in all The function remains permanently switched on after it methods.

  • Page 72: Zero Adjustment

    10. Zero adjustment Zero adjustment is necessary When performing the zero adjustment observe the following points: after changing the lamp Only use a clean, scratch-free round cell with after the error message, PhotoCheck (AQA1) distilled water. A prepared zero cell is provided with occurs your photometer.

  • Page 73: Meter Setup

    11. Meter Setup – To switch on the photometer, open the cover. – Press – In the setup menu, call up the meter setup submenu. The following display appears: This chapter describes four functions of the meter setup menu: select language set date/time Performing a meter reset system info...

  • Page 74: Setting The Date/Time

    11. Meter Setup 11.2 Setting the date/time – Call up the set date/time menu item. – Input the date using – Confirm with – Input the time with – Confirm with 11.3 Reset It is possible to reset the photometer to its factory All AQA functions are retained when meter setup is used.

  • Page 75: System Info

    11. Meter Setup 11.4 System info – Call up the system info menu item. Sample display...

  • Page 76: Updating Method Data

    12. Updating method data You will always find the latest method data for your To download and update the photometer method data photometer on the Internet. A method update contains via the built-in RS232 interface, you need the all new test sets and methods respectively. Additionally, following: minor modifications of already existing methods are transferred with it.

  • Page 77: Error Messages

    12. Updating method data During the download, the following display appears on the photometer screen: – After the download, confirm the "Data successfully downloaded" message. The download is finished. The photometer returns to the concentration measuring mode. You can check whether the new method data are stored in the photometer.

  • Page 78: Rs 232 C Interface

    13. RS 232 C interface Via the interface, data can be output to a printer and exchanged with a personal computer (PC) For this, the following items are available as accesso- ries: Printer cable Printer Interface cable Communication software. 13.1 Principle course of the remote control String to meter Reply from meter Operating mode...

  • Page 79: Output Format Of Measured Values

    13. RS 232 C interface 13.3 Output format of measured values Notes: Character Meaning Data fields are separated by spaces. consecutive number (not required for Character set: IBM, code page 437 interface commands CMES, CEXT and CBLA) Meaning of the special characters: method designation = Measuring with blank value (concentration) or I.

  • Page 80: Maintenance

    14. Maintenance 14.1 Changing the lamp – Connect the plug a of the new lamp – Switch off the photometer and disconnect it from the power line – Screw the lamp cover on again – Carefully turn up the photometer and park it safely –...

  • Page 81: Technical Data

    15. Technical Data Weight approx. 2.3 kg (battery version: Optical Filter photometer with reference 2.8 kg) measuring beam absorption measurement; principle simultaneous recording of all Meter safety EN 61010, IEC 1010 wavelengths Safety class EN 61010-1/class 3 Light source Tungsten halogen lamp, preset Power pack Receiver 6 x photo diode array...
  • Page 82 15. Technical Data Operating On/off switch actuated by Software settings when delivered elements opening/closing the lid of the cell Measured value shaft cover number: blank value is: Silicon keyboard with 4 function turbidity correct.: keys English language: Cell shaft Date of the last valid invalid (not yet measured) –...

  • Page 83: What To Do If

    16. What to do if… The display remains blank Connect the photometer to the line power via the power pack. when switched on In the case of battery operation: Battery empty, charging required (approx. 5h); line operation is possible without restrictions during charging time. Battery nearly empty.

This manual is also suitable for:

Photolab s6

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