Operating Instructions. METTLER TOLEDO DL37 KF Coulometer

Transcription

1 Operating Instructions METTLER TOLEDO DL37 KF Coulometer

2 Contents Contents Page. Safety measures 5 2. Introduction 6 2. Measurement principle 7 3. Setting up the system 8 3. Identification of parts Checking the operating voltage Printer paper loading 3.4 Installing the titration vessel Balance connection 3 4. Method configuration 4 4. General Basic structure Structure of the method parameter configuration Initial parameters in method No Titration Parameters (Titr Para) Endpoint of the titration (Limit or End Level) Stirring time (Delay; sec?) Control Gain Stable; µg Blank on / off Start auto / manu Titration parameters with DO337 Drying Oven Titration parameters with DO337 connected to the DL Pretreatment possibilities Calculation Parameters (Calcu Para) Parameters for results printout (Print Para) Parameters for graphics and data printout (Data List Para) Parameters for sample size (Size Para) Method selection and protection Initialization of all default parameters 35 METTLER TOLEDO DL37

3 Contents Contents Page 5. Titration Status diagram of titration The first titration Pretitration Titration with manual or automatic start Weight entry: before, during or after the titration Sample weight entry before the start of the titration Sample weight entry during the titration Sample weight entry after the titration Weight entry: automatic from the connected balance Series titration Water determination in solid samples by external extraction Titration of solid samples by an external dissolution Titration of solid samples by an external extraction Water determination using DO337 Drying Oven Functions General Reagent life: display, initialization and alarm setting (FUNCTION 0) Recalculation (FUNCTION ) Statistical evaluation of titration series (FUNCTION 2) Statistical evaluation of manually entered data (FUNCTION 3) Statistics: Deletion of single results in series (FUNCTION 4) Date and time setting (FUNCTION 5) RS-232C interfacing (FUNCTION 6) Display of the polarization potential and the results (FUNCTION 7) Purging during DO337 conditioning (FUNCTION 8) Special Keys The Key (the key with the switch function) The RESET Key The STIRRER and SPEED Keys The PRINT Key Instrument identification 69 2 METTLER TOLEDO DL37

4 Contents Contents Page 8. Maintenance Charging of memory backup battery Application of grease Septum replacement Silica gel replacement Long-term storage measures Catholyte replacement Anolyte replacement Cleaning detection electrode Cleaning inner burette Cleaning steps Drying steps Troubleshooting Error messages and malfunction rectification Power switch failure Stirrer malfunction Background level excessive Excess reagent consumption Endpoint not reached or reached too late Poor reproducibility of results Glass contact areas jammed Standard Equipment and Optional Accessories 83 Appendix A Schematic Diagram 88 B Specifications 89 C Display messages list 9 D Index 98 E ISO 900 certificate for METTLER TOLEDO 0 Declaration of System Validation 02 METTLER TOLEDO DL37 3

5 Fcc Contents rules FCC rules This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to both Part 5 of the FCC Rules and the radio interference regulations of the Canadian Department of Communications. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is like to cause harmful interference in which case the user will be required to correct the interference at his own expense. 4 METTLER TOLEDO DL37

6 Safety measures. Safety measures The DL37 has been tested for the experiments and intended purposes documented in these Operating Instructions. However, this does not absolve you from the responsibility of performing your own tests of the product supplied by us regarding its suitability for the methods and purposes you intend to use it for. You should therefore observe the following safety measures. Measures for your protection Ensure that you plug the power cable supplied into a receptacle outlet that is grounded! In the absence of grounding, a technical fault could be lethal. Switch the instrument off and disconnect the power cable before you open the housing or change blown fuses! An electric shock could be lethal. Never work in an environment subject to explosion hazards! The housing of the instrument is not gas tight (explosion hazard due to spark formation, corrosion caused by the ingress of gases). When using chemicals and solvents, comply with the instructions of the producer and the general lab safety rules! Measures for operational safety Check the set operating voltage before you switch on the instrument! The instrument may suffer damage if the operating voltage does not match the line voltage. Use only fuses of the type specified in the Operating Instructions! (Risk of fire) Have the instrument serviced only by METTLER TOLEDO Service! Always wipe off splashed liquids immediately! The instrument is not water-proof. Exclude the following environmental influences: powerful vibrations, direct sunlight, atmospheric humidity greater than 80%, temperatures below 5 C and above 35 C, powerful electric or magnetic fields! METTLER TOLEDO DL37 5

7 Introduction 2. Introduction Moisture in sugar or salt influences its pouring properties. Traces of moisture in brake fluid adversely affect the function of the vehicle brakes. Small amounts of water in aircraft hydraulic oil increase the risk of an emergency. Traces of moisture usually influence the quality of products and it is therefore often very important to know the exact value of the moisture content. With the METTLER DL37 KF Coulometer you can easily determine traces of water with a very high degree of accuracy. The DL37 has five built-in methods. With the DL37 you have the possibility to adapt the titration parameters (control gain, end point indication, etc.) to your titration problem to obtain an optimal measurement procedure (short titration time, high accuracy). The DL37 has an automatic start mode. You inject the sample, the titration then starts automatically as soon as the DL37 detects the added water. The DL37 offers the possibility of entering the sample weight before, during or after the titration; manually or transferred automatically from the connected balance. The DL37 and METTLER DO337 Drying Oven can be connected to a highly automated system. This system enables you to determine water in solids in an extremely simple operation. The DL37 has an automatic background (drift) determination, which is reconciled in the result calculation. The DL37 has a statistical evaluation feature (mean, standard deviation and coefficient of variance) and allows recalculation of results. The DL37 has a highly flexible result printout. It is possible to print out the titration curve and a list of the titration data (time, moisture content within time interval and accumulated moisture content). 6 METTLER TOLEDO DL37

8 Introduction 2. Measurement principle In the Karl Fischer moisture content measurement, water reacts with iodine and sulfur dioxide in the presence of a base and an alcohol. H 2 O + I 2 + SO 2 + CH 3 OH + 3RN [RNH] SO 4 CH 3 + 2[RNH]I () In the volumetric titration, iodine is added as a titrant. In the coulometric technique, iodine is electrolytically generated in the anolyte, which contains iodide. 2I I 2 + 2e (2) As long as water is present in the titration vessel the generated iodine reacts according to (). As soon as all the water has reacted, a small excess of iodine appears in the anolyte. This iodine is detected by the double platinum pin electrode and the iodine production is stopped. According to Faraday s law, the quantity of iodine produced is proportional to the current generated. In equation (), I 2 and H 2 O react with each other in proportion :. Therefore a mole of water (8 g) is equivalent to 2 x 96,500 coulombs, or 0.72 coulombs/ mg H 2 O. The total amount of moisture can thus be determined by measuring the total consumption of electricity. Display Detection/ control unit Microcomputer Printer Inner burette Detection electrode (double platinum pin electrode) Titration vessel Catholyte Cathode Membrane Anode Anolyte Rotor METTLER TOLEDO DL37 7

9 Setting up the system 3. Setting up the system 3. Identification of parts Printer Inner burette (integrated cathode/ anode combination) Titration cell desiccator Detection electrode (double platinum pin electrode) Septum (syringe inlet port) Titration cell Titration cell holder Display : Indicates method No., background level, status and data Keypad 0 I RS-232C BALANCE Electronic balance interface (option) Computer interface (RS232) (option) Power switch 8 METTLER TOLEDO DL37

10 Setting up the system Keypad METHOD µg/sec COND DATA. 3 2 * µ g METHOD PRE-TITR PRINT TITR.PARA FUNCTION RESET RESULT SIZE STIRRER SPEED CLEAR ENTER START Keys: METHOD Key for method selection (see chapter 4.8) TITR.PARA Key for setting titration parameters (see chapter 4.2) RESULT Key for setting calculation and printing parameters (see chapter ) SIZE Key for entering sample No. and sample weight (see chapter 4.7) PRE-TITR Key to start the pretitration (see chapter 5.3) FUNCTION Key for special functions (see chapter 6) STIRRER Key to switch the stirrer on/off (see chapter 7.3) SPEED Key to set the stirrer speed (see chapter 7.3) PRINT Key to print out all methods and function parameters (see chapter 7.4) RESET Key to reset all functions (see chapter 7.2) START Key to start a titration (see chapter 5) CLEAR ENTER Key to clear an entry Key to confirm a parameter entry Display: METHOD Display of the selected method µg/sec Display of the background level (drift) COND Display of the status * During pretitration Ready for titration DATA Display of the moisture content during titration METTLER TOLEDO DL37 9

11 Setting up the system 3.2 Checking the operating voltage Before switching on the instrument for the first time, make sure the voltage selector is set to the appropriate line voltage. Slotted screwdriver Voltage selector Spare fuse Current fuse Voltage selector AC power Connection to DO337 Line voltage Setting of voltage Fuse selector 00 V, 50 Hz 00 V T3,5L250V 20 V, 50/60 Hz 20 V T3,5L250V 220 V, 50 Hz 220 V T,6L250V 230/240 V, 50 Hz 240 V T,6L250V Voltage can be selected by the selector on the rear panel. 0 METTLER TOLEDO DL37

12 Setting up the system 3.3 Printer paper loading Load a new roll of paper on the holder bar and place in position. Lead paper under the drum. Select Print Titr. Para. Tear off excess paper. METTLER TOLEDO DL37

13 Setting up the system 3.4 Installing the titration vessel Set the power switch (on the side panel) to the OFF position. Connect the detection electrode, the anode and cathode as shown in the illustration. white red Filling the titration vessel with reagent WARNING Do not inhale or allow skin contact of Karl Fischer reagents! They are potentially hazardous. Anolyte Pour 00 ml of anolyte into the titration vessel. Catholyte Pour about 5 ml of catholyte into the cathode of the inner burette. Note: Adjust the catholyte level up to the 00 mark on the titration vessel. See also chapter 6.2: Reagent life. 2 METTLER TOLEDO DL37

14 Setting up the system 3.5 Balance connection When a balance is connected to the titrator, the sample weight can be transferred directly to the titrator. METTLER TOLEDO PM Balance Use a PM data interface and balance connection cable ME The data output of the connected PM balance must be configured as follows: Send Continuous Mode 2400 baud even parity METTLER TOLEDO AE Balance Use Option 0 and balance connection cable ME The data output of the connected AE balance must be configured as follows: Send Continuous Mode 2400 baud even parity cable shielding floating (no coding plug) ON METTLER TOLEDO AT Balance Use balance connection cable ME The data output of the connected AT balance must be configured as follows: Cont (Send Continuous Mode) 2400 bd (2400 baud) PAr E (even parity) HS Pause EOL clf METTLER TOLEDO AG/AB/PB/PR Balances Use LC-RS25 cable ME Using the 3 switches, the cable must be configured as follows: 7 (left switch) attachment of the DL37 3 (middle switch) 2400 baud 4 (right switch) 7 bit, even parity, none send continuous mode METTLER TOLEDO DL37 3

15 Method configuration 4. Method configuration 4. General The METTLER DL37 KF Coulometer has 5 methods stored for the determination of water. Each method contains all parameters which are used for the titration, the calculation and the record of a titration. These parameters can be modified to meet the requirements of individual titrations using the three function keys TITR.PARA, RESULT and SIZE. METHOD µg/sec COND DATA. 3 2 * µ g METHOD PRE-TITR PRINT TITR.PARA FUNCTION RESET RESULT SIZE STIRRER SPEED CLEAR ENTER START In a new METTLER DL37 KF Coulometer all 5 methods are initialized with default parameters for 5 different titrations (see 4..3.). With these methods you can start a titration without any change of parameter configuration. 4.. Basic structure A method consists of 5 groups of parameters, which can be selected with the three function keys TITR.PARA, RESULT and SIZE Function key Parameter group Description TITR. PARA Titr. Para (parameters for controlling the titration) RESULT Calcu Para (parameters for the result calculation) Print Para (parameters for the result printout) Data List Para (parameters for graphics and data printout ) SIZE Size (parameters for the sample) 4 METTLER TOLEDO DL37

16 Method configuration 4..2 Structure of the method parameter configuration For entering and changing these display lines, see the chapters 4.2, 4.5, 4.6, 4.7. TITR.PARA Delay; sec? ( sec) Limit; sec? ( sec) Control Gain? (-0) End Level; off / on End Level? ( sec) Stable; µg? Blank; on / off Start; auto / manu Oven; off / on Oven Temp;? (0-300 ) Pretreat; -3? Back; sec? Sampler; sec? Cell; sec? RESULT CALCU PARA PRINT PARA Calcu No. :, 5-6 Dimension : µg/mg ppm/% Wt : variable / constant Format fixed / variable DATA LIST PARA Print Time? Data List : on / off Graphic : off / Form / Form 2 (0-999 sec) Sample No. : on Size : on Result : on (rest off) Sample No. ; Date ; Lot No. ; Method No. ; Calcu No. ; Size ; Result ; End Level ; Back Ground ; Reagent ; Meas. Time ; on / off on / off on / off on / off on / off on / off on / off on / off on / off on / off on / off METTLER TOLEDO DL37 5

17 Method configuration SIZE Sample No.;? 0-0 Lot;? BG; µg/sec? Wt ; g? Wt 2; g? Wt 0; g? B; g? A; ppm? V; ml? Dens; g/ml? V2; l? Temp; C? The structure depends on the calculation method (Calcu No.) Calcu No. : Sample No.;? 0-0 Lot? BG? µg/sec Calcu No. 4 Sample No.;? 0-0 Lot? BG ; µg/sec? V ; ml? Dens ; g/ml? Calcu No. 2 : Sample No.; 0-0 Lot? BG : µg/sec? Wt : g? Wt 2 : g? Calcu No. 5 : Sample No. ;? 0-0 Lot? BG ; µg/sec? V2 ; l? Temp ; C? Calcu No. 3, 6 : Sample No. ;? 0-0 Lot? BG ; µg/sec? Wt ; g? Wt 2 ; g? Wt 0 ; g? B ; g? A ; ppm? 6 METTLER TOLEDO DL37

18 Method configuration 4..3 Initial parameters in method No. - 5 Sample measurement Direct liquid sample measurement Measurement of plastics, powder and samples with DO337 Drying oven Method Parameter TITR. PARA Delay; sec? Limit; sec? Control Gain? End Level; on End Level? Stable; µg? Blank; on Start; auto Oven; on Oven; Tem? Pretreat; -3? Back; sec? Sampler; sec? Cell; sec? on 0. µg/sec 0. µg/min on auto off on 0. µg/sec 0. µg/min on auto off sec 5.0 off 0. µg/min on auto on 50 C 80 sec 80 sec 20 sec sec 5.0 off 0. µg/min on auto on 50 C 80 sec 80 sec 20 sec sec 5.0 off 0. µg/min on auto off CALCU. PARA Calcu No., - 6 Dimension; ppm µg 2 ppm 2 ppm 2 ppm 2 ppm Variable Wt Variable Variable Variable Variable PRINT. PARA Fixed Format Fixed Format Sample No. Size Result Fixed Format Sample No. Size Result Fixed Format Sample No. Size Result Fixed Format Sample No. Size Result Fixed Format Sample No. Size Result DATA LIST. PARA Print Time? Data List; off Graphic; off 30 sec off off 30 sec off off 30 sec off off 30 sec off off 30 sec off off SIZE Sample No.? Lot? Wt; g? Wt2; g? g 0.0 g g 0.0 g g 0.0 g g 0.0 g Every method No. can be configured as a method together with a drying oven. Basically, the structure of every method can be changed to any desired form. Methods and 2 can therefore also be configured with the DO337 Drying Oven. METTLER TOLEDO DL37 7

19 Method configuration 4.2 Titration Parameters (Titr Para) Here you can set the control parameters for the titration. Display Delay ; sec? Limit ; sec? Description Stirring time before titration. ( sec) After pressing the START key the countdown of the remaining stirring time is displayed. Titration time. ( sec) A titration will be terminated after the time limit, if no end point is found. The time limit is not active if set to 0; in this case End Level must be set ON. Control Gain? Control Gain ( - 9) Use 2-3 for high reaction rate, 7-8 for low reaction rate, 4-6 normal. (Never use 0, iodine will not be generated.) End Level ; on 3 Titration termination by End Level ON: A titration will be terminated when End Level is reached. OFF: A titration will be terminated after the time limit. End Level? Value for End Level (0-999 µg/sec) normal 0. µg/sec Value above the baseline which determines the end point, baseline = background level (drift) before sample injection. Stable ; µg? Blank ; on 3 Change in the background (drift) (0-999 µg/min) normal 0. µg/min For status change Ready - Stable, see chapter 5.3. Automatic or manual background level (drift) compensation ON: The background level (drift) is automatically compensated. OFF: The background level (drift) is compensated by a manually entered value with the SIZE parameters. See chapter 4.7. Start ; auto 3 Automatic start of the titration (see also chapter 5.4) AUTO: Automatic start of the titration when moisture is detected MANU: Start of the titration with the START key Oven off 3 DO337 Drying Oven connected ON: DO337 Drying Oven connected. additional parameters, see chapter 4.3. OFF: DO337 Drying Oven not connected Note All parameters with the 3 sign can be changed with the key, see also chapter 7.. All parameters with the? sign require entry of a numeric value. 8 METTLER TOLEDO DL37

20 Method configuration 4.2. Endpoint of the titration (Limit or End Level) With the DL37 you have two possibilities to determine an endpoint. a) Limit You define a fixed titration time. The titration stops after the defined time. b) End Level You define an endpoint level. When the endpoint level is reached, the titration stops. You must define a Limit or an End Level, or both. If you define nothing, in other words Limit 0 sec and End Level OFF, you get an error message: Para set miss! If you set both, the first condition to be satisfied, stops the titration. Remarks regarding Limit The fixed titration time is used especially with the DO337 Drying Oven. As the Drying Oven is often very slow, an endpoint indication with the End Level would take a very long time. The fixed titration time is also used for titrations with a sluggish approach to the endpoint (due to side-reactions), especially if the end point level is not known. To switch off fixed titration time, set Limit to 0 sec. Remarks regarding End Level A higher value of the End Level reduces the titration time, but the titration error increases, especially if the sample releases its moisture slowly. Repeated analysis of an oil sample sometimes causes a shift to a higher background level (drift). In this case a low End Level setting results in failure to detect the endpoint. In the case of titrations with a sluggish approach towards the endpoint (due to sidereactions), a higher End Level can help reduce the error. METTLER TOLEDO DL37 9

21 Method configuration Titration curves of a rapid and a slow moisture release with two End Levels: µg H 2 O / sec L A L2 End 2 End 2 Start End Start End A: Background level (drift) L: High endpoint level (high value for End Level) L2: Low endpoint level (low value for End Level) End Endpoint with the high End Level End2 Endpoint with the low End Level If the End Level is set to 0 (with End Level ON), the titration will proceed until the background level (drift) reaches the value before sample injection Stirring time (Delay ; sec?) If you have defined a stirring time, the countdown of the remaining stirring time will be displayed after you have pressed the START key. You can use the stirring time with manual and automatic start. If you want to terminate the current stirring time, press the START key again and the titration will start immediately Control Gain The control gain is used to control the iodine production. With a high value of Control Gain the iodine production will be faster and therefore the titration time shorter, but the risk of overtitration will also be higher. For an optimal titration (short titration time without over-titration), the Control Gain must be adapted to the reaction rate. For normal reaction rates, use Control Gain 4-6. For low reaction rates (slow water release of the sample), use Control Gain 7-8. For high reaction rates use a low Control Gain 2-3 to avoid over-titration. 20 METTLER TOLEDO DL37

22 Method configuration Stable ; µg After a pretitration or titration the DL37 has two status modes: Ready or Stable. In these two modes, the titration cell is kept free from water by continuous titration. Status Ready: Background (drift) is not stable. Status Stable: Background (drift) is stable. The change from status Ready to Stable is defined with the parameter Stable. For example: Stable = 0. µg/min (background (drift) deviation per minute) If the change in the background (drift) is 0. µg/min or less, the status is Stable. If the change in the background (drift) is more than 0. µg / min, the status is Ready. The change to the status Stable does not depend on the background level (drift), but on the background (drift) stability. It is possible to be in the Stable mode with a high but stable background (drift). See also chapter Blank on / off (automatic or manual background (drift) compensation) Blank on: The background level (drift) is automatically compensated by the measured value of the background level (drift) before sample injection. Normally Blank on should be used. Blank off: The background level (drift) is compensated by the value entered through the SIZE parameters (BG µg/sec ;?). See chapter 4.7. When Blank off is selected, the background titration will be stopped by pressing the START key in the automatic and manual start mode Start auto / manu Start auto: Automatic start of the titration: Press the START key, the titration starts automatically as soon as the DL37 detects the added moisture. If no moisture is detected within minute after pressing the Start key, the DL37 will reset itself. If the parameter Blank is set to on, the DL37 compensates the background (drift) until the added sample is detected. Start manu: Manual start of the titration: Press the START key, inject the sample and press the START key again to start the titration. After the START key is pressed for the first time, the background titration stops. See also chapter 5.4. Titration with manual or automatic start. METTLER TOLEDO DL37 2

23 Method configuration 4.3 Titration parameters with DO337 Drying Oven 4.3. Titration parameters with DO337 connected to the DL37 In order to use the DL37 with the DO337 as a highly automated system, you must set the parameter Oven to on. Display Oven on 3 Oven Temp.? Description DO337 Drying Oven connected ON: DO337 Drying Oven connected OFF: DO337 Drying Oven not connected Set temperature for the DO337 (0-300 C) Pretreat; -3? Possibilities for the pretreatment (-3) For more details, see chapter Back; sec? Sampler; sec? Cell; sec? Time of back-purging (normally 80 sec) For more details, see Fig. Time of sampler purging (for eggplant-shaped sampler) (normally 80 sec) This is applied only with Pretreat For more details, see Fig. 2 Time for cell purging (normally 20 sec) For more details, see Fig. 3 Sampler purging Eggplant-shaped samp Cell purging Carrier gas Back purge Carrier gas Carrier gas Fig. : Back-purging Fig. 2: Sampler purging Fig. 3: Cell purging 22 METTLER TOLEDO DL37

24 Method configuration Pretreatment possibilities Pretreat (with the eggplant-type sampler) Pretreat;-3? Back ; sec? Select a BACK PURGE TIME (normally to 80 sec) Eggplant-type sampler Sampler ; sec? Select a PURGE TIME for the eggplant-type sampler (normally to 80 sec) Heating tube Rotate Cell ; sec? Set a CELL PURGE TIME (normally to 20 sec) Sample boat END Place the sample in the eggplant-type sampler and insert the sampler in the sample inlet of the DO337. Start the measurement sequence by pressing the START key, the sample boat will then move automatically to the sample inlet, back-purging will be performed (see Fig. ), followed by sampler purging (see Fig. 2) and finally cell purging (see Fig. 3). The DL37 will wait for background (drift) stability and will then tell you to insert the sample (you rotate the eggplant sampler to transfer the sample to the sample boat). After the START key has been pressed again, the sample boat will be moved automatically into the heating section. (For more details, see Operating Instructions of the DO337.) METTLER TOLEDO DL37 23

25 Method configuration Pretreat 2 (direct sample insertion through the sample inlet) Pretreat;-3? 2 Back ; sec? Cell ; sec? Select a BACK PURGE TIME (normally to 80 sec) Set a CELL PURGE TIME (normally to 20 sec) END Press the START key to start a measurement sequence. The sample boat moves to the sample inlet, back-purging is performed (see Fig. ), followed by cell purging (see Fig. 3). When the background becomes stable, insert the sample directly in the sample boat through the sample inlet port. Press START and the sample boat will be moved automatically into the heating area. (For more details, see chapter 5.9 or the Operating Instructions of the DO337.) Pretreat 3 (placement of the weighed sample in the sample boat) Pretreat;-3? 3 Back ; sec? Cell ; sec? Select a BACK PURGE TIME (normally to 80 sec) Set a CELL PURGE TIME (normally to 20 sec) END Place a weighed sample in a dry sample boat and position the boat below the sample inlet. Press the START key to start a measurement sequence. Back-purging will be performed (see Fig. ), followed by cell purging (see Fig. 3). When the background becomes stable, press START and the sample boat will be moved into the heating area. (For more details, see the Operating Instructions DO337.) 24 METTLER TOLEDO DL37

26 Method configuration 4.4 Calculation Parameters (Calcu Para) The three calculation parameters are part of the result parameters you can select in a method. The calculation parameters needed for every sample must be entered through the SIZE parameters, see chapter 4.7. Entry key Display Description RESULT Data List Para Select Calcu Para with the key Calcu Para ENTER Calcu No.:-6? Set the formula No. 2 Calcu No.:-6? 2 (formulas, see next page) ENTER Dimension: % Set the calculation result unit Dimension: ppm ENTER Constant Wt Constant sample size Variable Wt Variable sample size ENTER Constant sample size If you choose constant sample size, the DL37 will use the same sample size for every titration. This sample size must be entered as a SIZE parameter. The DL37 will not then request a weight entry. Variable sample size If you choose variable sample size, you can enter the sample size before, during or after the titration. If you do not change the sample size before or during the titration (with the SIZE parameter), the DL37 will request the sample size after the titration. If you have changed the sample size before or during the titration, the DL37 knows that you have already entered a value and will thus not request a weight. See also chapter 5.5. Note You can change all parameters with the sign using the key; see also chapter 7.. METTLER TOLEDO DL37 25

27 Method configuration Formula No. Description Formula Moisture calculation (default). Result in µg or mg. (Data - BG x t) BG = Background level entered with the SIZE key with Blank off t = Measurement time 2 Concentration calculation for weighed liquid or solid samples. Result in ppm or %. ( ) Data -BG x t Wt- Wt2 x 000 (ppm) 3 Concentration calculation for external dissolution of liquid or solid samples (sample dissolved in the solvent). Result in ppm or %. ( ) Data -BG x t Wt- Wt2 - AxB Wt0 (ppm) B+Wt0 x Wt0 x Concentration calculation for volumetrically measured samples. Result in ppm or %. ( ) Data -BG x t V x Dens x 000 (ppm) 5 Concentration calculation for volumetrically measured gaseous samples. Result in ppm or %. ( Data -BG x t ) x 22,4 x + T x 000 (ppm) V2 x Concentration calculation for external extraction of solid samples (sample insoluble in the solvent). Result in ppm or %. ( Data -BG x t) B x Wt- Wt2 Wt0 x A x B Wt0 (ppm) Calculation formula (Calcu No - 6) Data Result of the titration (in mg water) BG Background level (entered with the SIZE key), used when the Blank parameter is set to off. t Measurement time when Blank is set to on: The background (drift) is automatically compensated in the result calculation. Wt Total weight (sample & syringe) (in g) Wt2 Weight (syringe) (in g) A Moisture content of the solvent only (in ppm) B Total amount of solvent for the external extraction (or external dissolution) (in g) Wt0 Weight of the sample entered in B solvent (in g) V Injected volume of the sample (ml) Dens Density of the sample (g/ml) V2 Volume of the gas sample (L) T Temperature of the gas sample ( C) 22.4 Gas volume of mole at 273 K 8 Molecular weight of water 26 METTLER TOLEDO DL37

28 Method configuration 4.5 Parameters for results printout (Print Para) The Print parameters allow you to define the format of your printout for a particular method. With fixed format, Result, Size (sample weight) and Sample No. are automatically printed out. With variable format, you can select the different items to be printed out. Entry key Display Description RESULT Calcu Para 3 Select Print Para 3 with the - key. Print Para 3 ENTER Fixed Format 3 Select the measurement result printout format. Variable Format 3 Select the print/no-print of the following items. ENTER Sample No.; on 3 Sample No. ENTER Date; on 3 Date ENTER Lot No.; off 3 Lot No. ENTER Method No.; off 3 Method No. ENTER Calcu No.; on 3 Formula No. ENTER Size; on 3 Size parameter ENTER Result; on 3 Calculation result ENTER End Level; on 3 End point level ENTER Back Ground; on 3 Background level ENTER Reagent; off 3 Reagent life ENTER Meas. Time; on 3 Measurement time required Note You can change all parameters with the 3 sign using the key; see also chapter 7.. METTLER TOLEDO DL37 27

29 Method configuration Result printout with fixed format. Result printout with variable format. Selection from above 28 METTLER TOLEDO DL37

30 Method configuration 4.6 Parameters for graphics and data printout (Data List Para) The Data List parameters allow you to select the time interval at which the determined moisture content and the accumulated moisture content will be printed out (= data list). You can also choose between two graphical representations. Entry key Display Description RESULT Print Para Data List Para Select Data List Para ENTER Print Time? 30 Select the data list printing interval 6 0 Print Time? 60 The moisture content is stored in memory at this interval (up to 28 data point in memory) ENTER Data List; off Select the print/no-print of the data list Data List; on ENTER Graphic; off Select the graphical representation ( or 2) (see next page) Graphic; Form Graphic; Form 2 ENTER Note You can change all parameters with the sign using the key, see also chapter 7.. METTLER TOLEDO DL37 29

31 Method configuration Graphic Form Graphic Form 2 Measurement time elapsed (min.:sec.) (min:sec) Moisture content within an interval (µg) Integrated moisture content (µg) Time TIme vs. moisture content per interval Time TIme vs. integrated moisture content (µg) 30 METTLER TOLEDO DL37

32 Method configuration 4.7 Parameters for sample size (Size Para) The Size parameters allow you to define sample identification parameters and other parameters related to the result calculation. The parameters related to the result calculation depend on the calculation formula chosen for the active method. List of all SIZE parameters: Message Description Sample No.? 0-0 Enter the sample No. Lot? Enter the lot No. BG; µg/sec? 0 Enter the background level. Note: This is displayed only when the titration parameter Blank is off (see also chapter 4.2.5). Wt; g? Sample size with tare (g). Wt2; g? 0.0 Remainder with tare (g). Wt0; g? Sample weight in extraction solvent (g). B; g? 0.0 Extraction solvent weight (g). A; ppm? 0.0 Moisture content in extraction solvent (ppm). V; ml?.00 Injected sample volume (ml). Dens; g/ml?.000 Sample density (g/ml). V2; l?.000 Gaseous sample volume (l). Temp; C? 25.0 Gas temperature ( C). Sample No. S a m p l e N o.? 0-0 Lower Sample No. Sample No. of the series (0-99) Higher Sample No. Series No. (0-99) With every titration the Lower Sample No. is automatically incremented by one. To start a new series, enter a new Higher Sample No. (the Lower Sample No. will be automatically set to 0). By entering a Higher Sample No. the results memory of this Series No. will be cleared. For statistical evaluation, see also chapters 6.4.and 6.6. For series titration, see also chapter 5.7. To enter only a Lower Sample No.: Press 0 5 ENTER XX - 05 is set. METTLER TOLEDO DL37 3

33 Method configuration Regarding Lot No.: You can use the Lot No. for the sample identification. To enter the Lot No. you can use all numeric keys and also the key. (The key has no special function in this case.) Regarding Wt0, Wt and Wt2 You can use these weights manually or with the key if a balance is connected to the DL37. See also chapter 5.5. and 5.6. The structure of the SIZE menu depends on the chosen calculation method (Calcu No.). If the calculation method needs definite parameters, these parameters will automatically be requested in the SIZE menu. The structure depends on the calculation method (Calcu No.) Calcu No. : Sample No.;? 0-0 Lot? BG? µg/sec Calcu No. 4 Sample No.;? 0-0 Lot? BG ; µg/sec? V ; ml? Dens ; g/ml? Calcu No. 2 : Sample No.; 0-0 Lot? BG : µg/sec? Wt : g? Wt 2 : g? Calcu No. 5 : Sample No. ;? 0-0 Lot? BG ; µg/sec? V2 ; l? Temp ; C? Calcu No. 3, 6 : Sample No. ;? 0-0 Lot? BG ; µg/sec? Wt ; g? Wt 2 ; g? Wt 0 ; g? B ; g? A ; ppm? 32 METTLER TOLEDO DL37

34 Method configuration Example of SIZE parameter entry External dissolution g salicylic acid in g methanol. Water content of the methanol: ppm Calculation formula No. 3 Entry key Display Description SIZE Sample No.? 0-04 Enter new sample No. to start a new series 0 2 Sample No.? 02-0 ENTER Lot? Enter a lot No Lot? ENTER Wt; g? Enter the sample weight before, during or after the titration ENTER Wt2; g? 0.0 ENTER Wt0; g? Wt0; g? Sample weight dissolved in solvent ENTER B; g? B; g? Weight of the solvent ENTER A; ppm? A; ppm? Water content of the solvent ENTER 2.02 Stable SIZE Sample No.? 02-0 By resetting the sample weight RESET 2.02 Stable entry you can ensure that the DL37 will request the weight after the titration METTLER TOLEDO DL37 33

35 Method configuration 4.8 Method selection and protection The METTLER DL37 KF Coulometer always has one of the 5 methods in its memory. If you change some parameters, e.g. in TITR.PARA the values of the current method will be overwritten and therefore the original method lost. It is, however, possible to protect a method against inadvertent parameter alteration. Once a method is protected, the titration, calculation and printing parameters can not be changed unless the protection is cancelled. The size parameters (sample No., sample weight, etc.) are not protectable and can therefore always be changed. If a selected method is protected, pressing the TITR.PARA or RESULT key causes an error message on the display: Protected!. Example of method protection: Entry key Display Description METHOD Method No.: -5? Current preset method No. is displayed. 2 Method No.: -5? 2 Enter a method No. ENTER Protect: off 3 Select whether to protect the method. Protect: on 3 ENTER Note You can change all parameters with the 3 sign using the key, see also chapter METTLER TOLEDO DL37

36 Method configuration 4.9 Initialization of all default parameters It is possible to reinitialize all 5 methods in the DL37 by selecting method 99. The default parameters set in the factory will be loaded again. (Parameters, see chapter 4..3.) This is the procedure: Entry key Display Description METHOD Method No.; - 5? Enter method No Method No.; - 5? 99 ENTER All Reset (ENTER) ENTER Switch power OFF and after 5 sec switch power ON Caution If you do not switch off the DL37 after initialization (load method 99), all parameters will be changed to undefined values! Caution With the above initialization other parameters will also be reset: Reagent Life of anolyte and catholyte set to 0. Reagent Life Alarm limits will be initialized (anolyte 500 mg, catholyte 200 mg). Reagent Life to control alarm will be switched off. RS-232C interface configuration will be initializied. Method No. will become the current method. METTLER TOLEDO DL37 35

37 Titration 5. Titration 5. Status diagram of titration Power on Standby Display: "Pre-Titr" flashes PRE-TITR Pretitration The solvent is titrated out Display:"Pre-Titr" PRE-TITR Ready Background (drift) not stable Display:"Ready" Stable Background (drift) stable Display:"Stable" START RESET TITRATION 36 METTLER TOLEDO DL37

38 Titration 5.2 The first titration In a new DL37 there are 5 initial methods with default parameters for 5 different titrations. (Parameters, see 4..3) With these methods you can start a titration without changing parameters. Start of the first titration: Set up the METTLER DL37 KF Coulometer as described in chapter 3. Turn on the power switch. Pre-Titr flashes on the display. Start pretitration: Press the PRE-TITR key; the pretitration will start. Wait until the display shows Stable. The DL37 is now ready for the titration. Choose method No 2: Press METHOD key, enter 2 and confirm with ENTER. Run titration Press START key. Inject a sample using a syringe through the septum (for example ml methanol). (This must be accomplished within min otherwise the DL37 reverts back to the stable state.) The titration starts automatically. When the titration is finished, the DL37 requests the sample weight: The display shows: Wt; g? Enter the sample weight and confirm with ENTER. The display now shows: Wt2; g? Confirm this with ENTER. The result is displayed and printed out. The DL37 is now ready to run the next titration. The titration cell is kept free from water by continuous titration. The display shows Stable. METTLER TOLEDO DL37 37

39 Titration Entry key Display Description PRE-TITR Pre-Titr (flashing) Standby. * Pre-Titr Pretitration.25 Ready Wait until the display shows Stable 2.02 Stable METHOD Method No. ; -5? Choose method 2 2 Method No. ; -5? 2 ENTER Protect; off! ENTER 2.03 Stable DL37 is ready for titration START 2.0 Samp. In. Inject the sample Must be accomplished within min 2.73 * 45.8 µg Wt; g? Titration in progress terminated Enter the sample weight Wt; g? ENTER Wt2; g? 0.0 ENTER ppm The result is displayed and printed 2.02 Stable DL37 is ready for the next titration 5.3 Pretitration Turn on the power switch. On the display Pre-Titr flashes (the DL37 is in the Standby mode). Press the PRE-TITR key in order to start the pretitration. If the stirrer is not active, press the STIRRER key (see also chapter 7.3) After the pretitration the DL37 switches to the modes Ready and Stable Status: Pre-Titr The solvent is titrated out. Status: Ready The change in the background (drift) is 0.5 µg H 2 O / min or less. Ready for rough measurement. Status: Stable The change in the background (drift) is 0. µg H 2 O / min* or less Stable background (drift). Ready for accurate measurement. The titration cell is kept water-free by continuous titration. * This value, the background (drift) stability ( µg H 2 O / min), can be set in the titration parameters. (Stable; µg? ). See chapter METTLER TOLEDO DL37

40 Titration It is possible to start the titration in the Ready or Stable mode. After the titration the DL37 always returns to the mode Ready or Stable depending on the background stability. Entry key Display Description PRE-TITR * Pre-Titr Ready Pretitration in progress Rough measurement ready Background (drift) not stable 2.02 Stable High accuracy measurement ready Background (drift) stable Note If you reconfigure the DL37 or replace the reagents, a higher amount of moisture will enter the titration vessel. In this case it may take longer to achieve the Ready and Stable status. Display status Stable: METHOD µg/sec COND DATA. 0 2 S t a b l e µ g Background level (µg H 2 O/sec) Status display Method No. Stop Pretitration In order to exit the status Pre-Titr, Ready or Stable, press the PRE-TITR key. The status indicated on the display: Pre-Titr flashes. During this time moisture (drift) is not titrated and the instrument is thus not ready to start a titration. To start the pretitration, press the PRE-TITR key. See also the chapter 5., Status diagram of titration. METTLER TOLEDO DL37 39

41 Titration 5.4 Titration with manual or automatic start With the DL37 you can choose between a manual or an automatic start. This selection can be done in the Titration Parameters (TITR.PARA), Parameter: Start; auto / manu, see chapter 4.2. Manual Start With the Manual Start you start the titration with the START key, add the sample and confirm the sample addition by pressing the START key again. After the START key is pressed for the first time, the continuous titration to keep the cell water-free will be terminated. Entry key Display Description START 2.0 Samp. In. Inject the sample 2.03 Start Display flashes! START 2.73 * 45.8 µg Titration in progress Wt; g? Enter the sample weight Wt; g? ENTER Wt2; g? 0.0 ENTER ppm The result is displayed and printed 2.02 Stable DL37 is ready for the next titration Automatic Start With the Automatic Start you start the titration with the START key and add the sample; the titration starts automatically when moisture is detected. Note: If moisture is not detected within minute, the moisture content is judged to be 0 and the system reverts to the stable state. After the START key is pressed, there is a continuous titration to keep the cell water-free until a higher moisture concentration is detected; this starts the titration. Entry key Display Description START 2.0 Samp. In. Inject the sample Must be accomplished within min 2.73 * 45.8 µg Titration in progress Wt; g? Enter the sample weight Wt; g? ENTER Wt2; g? 0.0 ENTER ppm The result is displayed and printed 2.02 Stable DL37 is ready for the next titration 40 METTLER TOLEDO DL37

42 Titration 5.5 Weight entry: before, during or after the titration With the DL37 you can enter the sample weight before, during and after the titration Sample weight entry before the start of the titration If you already know the sample weight before you start the titration, the weight can be entered as a SIZE parameter. The DL37 recognizes that you have already entered the weight and will not request the weight after the titration. Entry key Display Description SIZE Sample No.? 0-0 ENTER Lot? ENTER Wt; g? Enter the sample weight Wt; g? ENTER Wt2; g? 0.0 ENTER 2.02 Stable DL37 is ready for the titration START 2.02 Samp. In. Inject the sample Must be accomplished within min 2.87 * 35.3 µg Titration in progress ppm The result is displayed and printed 2.02 Stable DL37 is ready for the next titration Sample weight entry during the titration In the case of a long titration time, it is useful to enter the sample weight during the titration. It is possible to enter this weight as a SIZE parameter when a titration is running. The DL37 will recognize that you have already entered the weight and will not request it after the titration. METTLER TOLEDO DL37 4

43 Titration Entry key Display Description START 2.0 Samp. In. Inject the sample Must be accomplished within min 2.33 * 5.8 µg Titration in progress SIZE Sample No.? 0-0 ENTER Lot? ENTER Wt; g? Enter the sample weight Wt; g? ENTER Wt2; g? 0.0 ENTER 2.87 * 35.3 µg Titration is still in progress ppm The result is displayed and printed 2.02 Stable DL37 is ready for the next titration Sample weight entry after the titration If you do not enter the sample weight before or during the titration, the DL37 will request the weight after the titration. Entry key Display Description START 2.0 Samp. In Inject the sample Must be accomplished within min 2.73 * 35.8 µg Titration in progress Wt; g? The titration is finished The DL37 is waiting for the weight Wt; g? ENTER Wt2; g? ppm The result is displayed and printed 2.02 Stable DL37 is ready for the next titration Caution! Each time you run through the SIZE parameters, even if you do not change the weight parameters, the DL37 will assume a weight has been entered and will take the value in Wt and Wt2 as the sample weight; it will then not request the weight after the titration. 42 METTLER TOLEDO DL37

44 Titration Avoid an unintentional weight entry; delete the weight entry. If you change sample No. or Lot, terminate the first weight parameter with RESET. If you are unsure whether a weight has already been entered for the titraiton, you can cancel the weight entry with RESET. Entry key Display Description SIZE Sample No.? 0-0 ENTER Lot? ENTER Wt; g? RESET The weight entry is deleted The DL37 requests the weight after the titration 5.6 Weight entry: automatic from the connected balance With the DL37 you can enter the sample weight manually using the keypad or automatically when a balance is connected. For information about the balance connections and configurations, see chapter 3.5. You can activate the weight transfer by pressing the Key This is possible when you have to enter a weight: Wt, g? Total weight (sample & syringe) Wt2, g? Tare weight (syringe) Wt0, g? Sample weight for external extraction (Calcu No. 3) If you determine the sample weight by back weighing, enter the weight of the sample as Wt and set Wt2 to zero. With the weight transfer from the balance this weight will be negative, but for the result calculation the minus sign will be ignored by the DL37. Note The unit of weight value will not be checked. METTLER TOLEDO DL37 43

45 Titration Entry key Display Description START 2.0 Samp. In. Inject the sample Must be accomplished within min 2.73 * 45.8 µg Titration in progress Wt; g? Titration terminated Enter the sample weight ENTER ENTER Wt2; g? ppm The result is displayed and printed 2.02 Stable DL37 is ready for the next titration Result printout with a weight transfer from the balance: 44 METTLER TOLEDO DL37

46 Titration 5.7 Series titration The DL37 is suitable for series titration. The two-figure sample number includes series No. and sample No. of the series. S a m p l e N o.? 0-0 Lower Sample No. Sample No. of the series Higher Sample No. Series No. Every titration automatically increments the Lower Sample No. by one. To start a new series, enter a new Higher Sample No. (The Lower Sample No. will be automatically set to 0. ) This entry clears the results memory for the statistics calculation. For statistical evaluation, see also chapter 6.4.and 6.6. Entry key Display Description SIZE Sample No.? 0-0 Enter a new sample No. to start a new series 7 Sample No.? 7-0 ENTER Lot? RESET The weight entry is deleted The DL37 requests the weight after the titration METTLER TOLEDO DL37 45

47 Titration Example of a series: 46 METTLER TOLEDO DL37

48 Titration 5.8 Water determination in solid samples by external extraction With the DL37 it is not possible to open the syringe inlet port stopper in order to add a solid sample, as too much moisture would enter into the titration vessel. Water absorption of an open syringe inlet port during 5 seconds (approx. 50% relativ humidity) is approx. 70 µg water! For water determination in solids you must use external dissolution or an external extraction and add the sample with a syringe. External dissolution for solid samples which are soluble in a solvent. External extraction for solid samples which are not soluble in a solvent. The METTLER DL37 KF Coulometer has special calculation formulas (Calcu No. 3 and 6) for both methods. This allows you to perform a water determination for solids without a manual calculation. Calculation formula No. 3 for external dissolution (for solid samples which are soluble in a solvent): ( ) Data -BG x t Wt- Wt2 B+Wt0 x x A x B ( Wt0 Wt0 ppm ) Calculation formula No. 6 for external extraction (for solid samples which are not soluble in a solvent): ( Data -BG x t) B x Wt- Wt2 Wt0 x A x B ( ppm) Wt0 Data Result of the titration (in mg water) BG Background level (entered with the SIZE key), used when the Blank parameter is set to off t Measurement time if Blank is set on : the background (drift) is automatically compensated in the result calculation of the titration. Wt Total weight (sample & syringe) (in g) Wt2 Weight (syringe) (in g) A Moisture content of the solvent only (in ppm) B Total amount of solvent for the external extraction (or external dissolution) (in g) Wt0 Weight of the sample entered in B solvent (in g) METTLER TOLEDO DL37 47