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DECADE Digital Electrochemical Amperometric Detector user manual Edition 9, 2007 120.0010 Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
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1 DECLARATION OF CONFORMITY We Antec Leyden B.V., Zoeterwoude, The Netherlands, declare that the product Electrochemical Detector DECADE (p.n. 120.0035) to which this declaration relates, is in conformity with the following directives: Safety (73/23/EEC) Safety requirements for laboratory equipment (Class I, Installation cat.
2 DECADE user manual, edition 9 Intended use For research purposes only. While clinical applications may be shown, this instrument is not tested by the manufacturer to comply with the In Vitro Diagnostics Directive. WEEE directive All equipment of Antec Leyden which are subjected to the WEEE directive shipped after August 13, 2005 are compliant with the WEEE marking requirements. Such products are labelled with the “crossed out wheelie”, depicted on the left site.
3 Symbols The following symbol are used on the rear panel and oven compartment of the DECADE: Consult the manual for further safety instructions Frame or chassis ground terminal The following pictograms are used in the DECADE II manual: Caution Caution, risk of electric shock or other electrical hazard (high voltage) Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
4 DECADE user manual, edition 9 Safety practices The following safety practices are intended to insure safe operation of the equipment. Electrical hazards The removal of protective panels on the instrument can result in exposure to potentially dangerous voltages. Therefore, disconnect the instrument from all power sources before disassembly. Untrained personnel should not open the instrument.
5 socket. The power source should exhibit minimal power transients and fluctuations. Replace faulty or frayed power cords. Place the detector on a flat and smooth surface. Do not block the fan located at the bottom of the detector. Blocking the fan will impair the cooling capability of the power supply. General precautions Perform periodic leak checks on LC tubing and connections. Do not close or block the drain. Do not allow flammable and/or toxic solvents to accumulate.
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7 Table of contents DECLARATION OF CONFORMITY 1 Intended use 2 WEEE directive 2 ROHS directive 2 Symbols 3 Safety practices 4 General precautions 5 Spare parts and service availability 5 DECADE electrochemical detector 11 Installation guide 13 Unpacking 13 Installation 13 HPLC connections 14 The DECADE controller 19 Introduction 19 Overview of all DECADE screens 20 Parameters 22 Data acquisition 29 Introduction 29 Internal organisation 29 Integrator output 30 Recorder output 31 Integrator vs.
8 DECADE user manual, edition 9 Step by step example (DECADE = Slave) 42 Hardware connections: 42 Programming the AUTO mode: 43 Interrupting a time file: 44 Other events 45 Inject/load and inject marker 45 Hold/busy 46 Overload 46 Auto zero 46 To pos A, B 46 Cell on (off) 46 Programming output functions 46 TTL contacts 47 Pulsed amperometric detection 51 Introduction 51 Pulse settings 53 Optimisation of wave forms 54 Recorder output frequency 54 Peak width and integrator frequency 55 Working electrode mat
9 Rear panel 71 TTL inputs 71 RS232C 71 Troubleshooting guide 73 No detector response 73 High cell current 73 Noisy baseline 73 Decreased sensitivity (low S/N ratio) 73 Baseline oscillations 74 Saturation of output 74 Pulse damper 75 Dummy cell 76 Index 77 Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
10 DECADE user manual, edition 9 Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
Chapter 1 DECADE electrochemical detector C H A P T E R 11 1 DECADE electrochemical detector Congratulations on your purchase of the DECADE. This detector enables you to perform all applications using electrochemical detection. The DECADE includes a highly stable Faraday-shielded oven compartment accommodating column and flow cell. This flow cell has surprised researchers for its unsurpassed S/N ratio and therefore you now possess the best possible combination for extremely sensitive EC analyses.
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CHAPTER 2 Installation guide C H A P T E R 13 2 Installation guide Unpacking Inspect the transport box for possible damage as it arrives. Immediately inform the transport company in case of damage, otherwise she may not accept any responsibility. Keep the transport box as it is designed for optimum protection during transport and it may be needed again. Carefully unpack the system and inspect it for completeness and for possible damage.
14 DECADE user manual, edition 9 line voltage. If not correct, this insert has to be reversed. Use only a supply appliance with protective grounding. The fuses are included in the line connector. The correct values are given on the rear panel for the different line sources. For 110 V (AC) ± 10%, use two 3.2 AT fuses (slow, ¼” x 1¼ ”, UL/CSA). For 220 V (AC) ± 10%, use two 1.6 AT-fuses (slow, 5 x 20 mm, IEC127). 4. Switch ‘on’ the DECADE by the mains switch on the rear panel.
CHAPTER 2 Installation guide 15 Fig. 2. Installation of the DECADE. 8. If a manual injector is applied, it is only part of the Faraday shield if the yellow wire from the cell cable is clamped on a metal part of the injector. The other end of the yellow cable is connected to ‘SHIELD’ on the connection plate for the flow cell cable. The sensor cable must be connected to the phone jack (P1) to make the LOAD/INJECT output on the rear panel functional. If no injector is mounted a plug is installed.
16 DECADE user manual, edition 9 If the ISAAC reference electrode is used, add 2 mmole/l chloride ions (e.g. KCl or NaCL) to the mobile phase. Equilibrate HPLC and continue installation. 12. Before connecting a new column read the manufacturer’s instructions. Pre-conditioning of the column may be necessary. A pre-conditioned column is electrochemically clean. If not, the background current may be unacceptably high.
CHAPTER 2 Installation guide The DECADE has been developed for continuous operation. For maximum stability it is advised to leave the system ON continuously. If preferred, the flow cell may be switched OFF at night. Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
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CHAPTER 3 The DECADE controller C H A P T E R 19 3 The DECADE controller Introduction The DECADE has been designed for maximum functionality and ease of use. The control of ECD parameters is such that without reading this chapter, it should be possible to operate the detector. This chapter is intended as a reference guide in case questions arise during operation. The information shown in the numerous screens is presented in alphabetical order.
20 DECADE user manual, edition 9 Overview of all DECADE screens Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
CHAPTER 3 The DECADE controller Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
22 DECADE user manual, edition 9 Parameters Actor (AUTO) PRGR control Controls the electrically actuated injector, during execution of a time file. Forces this valve to load (‘LD’) or inject (‘INJ’) (see page 37). ADD (AUTO) PRGR function Adds the current data line to the time file. Confirmation is asked for if an existing time is overwritten. As time 00’ 00” always exists, changing this time results in an overwrite warning (see page 37).
CHAPTER 3 The DECADE controller 23 Cycle PULS SET2, PULS STAT status Displays the total duration of one pulse (t1 + t2 + t3). As from each cycle only one data point is sent to the recorder output, this duration determines the frequency of the recorder output (see page 51). Cycle SCAN SET control Controls the nature of the cycle: half, full and continuous. ‘Half’ means that the cell potential runs from E1 to E2 and stops at E2.
24 DECADE user manual, edition 9 time file when the baseline is drifting. The available drift monitor settings depend on the range selected at time 00:00 in the time file (see page 37). Can be set between 0.1 pA/min and 10 nA/min. E1, E2, E3 PULS SET2 control Controls the cell potential settings of the pulse. A change in E1 has to be confirmed with the ‘#’-button (see page 51). Ec (AUTO) PRGR (DC only) Controls the cell potential in a time file (see page 37).
CHAPTER 3 The DECADE controller 25 Interrupts the execution of a time file or scan. Toggles between 1 and 0. Pressing the hold button again continues the time file or scan were it was stopped (see page 37). Icell DC STAT, PULS STAT, SCAN STAT status Displays the true, non-compensated cell current, i.e. unaffected by zero or offset. The cell current is one of the most important parameters in ECD.
26 DECADE user manual, edition 9 ‘0000’ corresponds to the four output controls at the rear panel of the controller (from left to right: relay 2, relay 1, aux 2, aux 1). The position indicated on rear panel refers to the ‘0000’ setting (see page 37). PREV DC SET, AUTO SET, PULS SET1, SCAN SET Returns to previous screen.
CHAPTER 3 The DECADE controller (AUTO) PRGR Scrolls through a time file (see page 37). 27 function SET DC STAT, AUTO RUN, PULS STAT, SCAN STAT) Returns to the previous (xx SET) screen. function SET1, SET2 PULS SET2, PULS STAT Returns to PULSE SET screen 1 or 2 function START AUTO RUN, SCAN STAT function In the DC and pulse mode (master if cycles >1): toggles between STOP and START to control the execution of a time file. In the scan mode START starts a scan (see page 59).
28 DECADE user manual, edition 9 Time (AUTO) PRGR control Controls the time to execute a data line in a time file, can be set with one second resolution. Maximum time is 999 min and 59 s. The time to stop the execution of a time file must be programmed by the CycleTime in the AUTO SET screen (see page 37). Toven DC STAT, PULS STAT status Displays the actual (left value) and the pre-set oven temperature (right value, set in ‘xxSET’). Toven DC SET, PULS SET1 control Controls the temperature of the oven.
CHAPTER 4 Data acquisition C H A P T E R 29 4 Data acquisition Introduction One of the characteristics of electrochemical detection is its tremendous dynamic range. In amperometric detection peak heights may vary from microamperes down to the pico-ampere range. The DECADE covers such a wide range from 5 µA down to 10 pA full scale, without being limited by electronic noise. The DECADE is equipped with two output connections for data acquisition, the recorder (‘REC’) and the integrator output (‘INT’).
30 DECADE user manual, edition 9 respectively. These are the three DECADE integrator ranges that can be set in the ‘Range select’ screen. Fig. 5. The DECADE ‘Range select’ screen. The 10 nA/V corresponds to 100 nA full scale on the integrator output (=10V). The integrator range selection is the first step in the signal pathway (Fig. 4). It affects both the integrator and the recorder output and has several important consequences for data acquisition (Table I). Table I.
CHAPTER 4 Data acquisition 31 When data are obtained from the integrator output, it is obvious that the pA range allows the highest sensitivity. Each range has a different maximum zero compensation (Table II). For example, in the nA range a current of 100 nA full scale can be managed. Together with a zero compensation of 160 nA, the maximum current that can be handled is 260 nA. Due to the nature of data generation the integrator output is unusable in the pulse and scan mode.
32 DECADE user manual, edition 9 There is much overlap in the recorder range settings offering flexibility as to maximum zero compensation (Table IV). For example, if a chromatogram is acquired at 10 nA, the nA or µA range can be selected (Table IV). With a high background current the µA is chosen (max. 16 µA compensation), at a low background the nA range is preferred (max. 160 nA compensation). The resolution of the zero compensation is 16 bits per selected integrator range.
CHAPTER 4 Data acquisition 33 Fig. 7. A ‘stepwise’ pattern after magnification of a chromatogram. This phenomenon will not occur at the integrator output because this output is purely analog and therefore, in principle, with infinite resolution. Integrator vs. recorder output In the pulse and the scan mode, only the recorder output is suitable for data acquisition. In the DC mode both outputs can be used, in that case a choice has to be made.
34 DECADE user manual, edition 9 Fig. 8. The clean signal from the integrator output (A) is smoothened by integrator software using a running average filtering (C). This results in a similar chromatogram as obtained from the recorder output using a rise time filter of 1 s (B). Offset A maximum offset of +50% and - 50% in 10% steps can be achieved, active on both the integrator and the recorder output. On the recorder output the offset is given as the percentage of the recorder range setting.
CHAPTER 4 Data acquisition 35 Table V. Effect of recorder range on the offset of the 10 V integrator output. pA Range nA µA 10% 20% Offset 30% 40% 50% 10 20 50 100 200 500 1000 2000 5000 0.1 0.2 0.5 1.0 2.0 5.0 10.0 20.0 50.0 0.01 0.02 0.05 0.10 0.20 0.50 1.00 2.00 5.
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CHAPTER 5 AUTO mode and time files C H A P T E R 37 5 AUTO mode and time files Introduction The AUTO mode of the DECADE enables a time-based, automated and full parametric control of electrochemical detection (ECD). This is particularly useful when during a run or between runs settings have to be changed such as the sensitivity, auto zero or control of external equipment (i.e. trigger to start integration software etc.).
38 DECADE user manual, edition 9 switched back to ‘load’ to enable continuous refilling of the injection loop. At time 1:26 the sensitivity is increased by a factor of 100 from 50 nA/V to 0.5 nA/V, together with an auto zero command. After passage of the small peak, the range is switched back to 50 nA/V. At t=3:05 the end of the chromatographic run is programmed in the ‘AUTO SET’ screen, using the ‘CycleTime’ parameter.
CHAPTER 5 AUTO mode and time files 39 drift monitor remains active. When the drifting baseline is within the pre-set limit the drift monitor is deactivated, and the run continues. The drift monitor is useful when, for example, after each run a cleaning pulse is programmed to reduce fouling of the working electrode. A cleaning pulse consists of e.g. a 10 seconds potential step at -1V. Fig. 11. Programming the drift monitor in the ‘AUTO SET’ screen.
40 DECADE user manual, edition 9 3. 4. In this example the integrator is connected to the REC output at the rear panel of the DECADE. Prepare the LC-EC system for analysis. Programming the AUTO mode: 5. 6. 7. From the DECADE ‘Main’ screen, choose DC, and in the ‘Range select’ choose NEXT. In the ‘DC SET’ screen, set the temperature at the desired value (or choose ‘off’) and choose AUTO. You are now in the ‘AUTO SET’ screen in the AUTO mode.
CHAPTER 5 AUTO mode and time files 41 Data acquisition’, page 29, for specific details on differences between both modes. In our example the nA range is chosen, and confirmed with ‘ACCEPT’. The message ‘New time is saved’ is displayed. Choosing ‘SCROLL’ allows you to scroll through your time file. With ‘DEL’ an existing line in your time file can be deleted (after confirmation). 8. Step 7 is repeated for each line in the time file.
42 DECADE user manual, edition 9 Important note when using the drift monitor: If an injection or an external event is programmed at t = 0:00, these events are executed immediately while the drift monitor is putting the system on hold. This can be prevented by programming these events at t = 0:01. Furthermore, the duration of each run will always be at least one minute longer. In this minute the drift in the baseline is monitored. Interrupting a time file: 12.
CHAPTER 5 AUTO mode and time files 2. 3. 43 required between ‘COMMON’ and ‘START’ to start a time file. Consult your autosampler manual for details on connecting the external contact to a relay. Connect relay 1 to ‘RESET’ and common as shown in Fig. 13A. From DECADE software version 3.00 and higher: a RESET is not required between runs, this input has been inactivated (Fig. 13B). Connect your integrator to the REC output at the rear panel of the DECADE. Fig. 13.
44 DECADE user manual, edition 9 ‘RESET’ of the DECADE is required. This is necessary to be ready for the next run. In our example the following line has to be programmed: This activates the ‘relay1’ output (‘0100’) for 1 second, just before ending the time file. This relay has been connected to the ‘RESET’ input (Fig. 13A). Note that the ‘RESET’ function overrules ‘CycleTime’. Immediately after this function, the execution of the time file is interrupted, whether the cycle time is met or not.
CHAPTER 5 AUTO mode and time files 45 9. If ‘STOP’ is chosen from the keyboard, the execution of the time file is interrupted. To start again, an external ‘RESET’ and ‘START’ (or ‘RUN’ from keyboard) command is required. Software version 3.00 and higher: the STOP command toggles between STOP and START to control the execution of a time file. STOP also deactivates the outputs Aux 1 and 2, and Relays 1 and 2 (status: 0000). 10.
46 DECADE user manual, edition 9 Hold/busy The hold/busy is a double function. Input: when a time file is executed in the slave mode, the timer can be stopped externally by connecting ‘HOLD’ and ‘COMMON’ as described above (Fig. 14). The timer continues after disconnection. Output: the ‘BUSY’ output is active (low) when during operation in the master or slave mode the DECADE is put on ‘hold’ by the drift monitor.
CHAPTER 5 AUTO mode and time files 47 contacts at the same time. For example, the command ‘0101’ activates AUX1 and relay 1 at the same time. Table VII. Outputs and commands, combinations are possible. output AUX1 AUX2 relay 1 relay 2 command 0001 0010 0100 1000 TTL contacts The DECADE uses TTL input contacts for START, RESET, AUTO ZERO, TO POS. A and TO POS. B. These contacts require a minimum TTL-low pulse duration of 100 ms to be activated.
48 DECADE user manual, edition 9 There are at least two ways to activate a contact by TTL-low. This can be done by making a contact closure of the input with common (see Fig. 13, ‘START’ command) or by using an external TTL contact which is made low (see Fig. 13, ‘RESET’ command). In the latter case it is important that the status of the external contact is known, and that the apparatus is connected to the same ground (by the mains power supply) as the DECADE. Table VIII.
CHAPTER 5 AUTO mode and time files 49 Table IX. I/O contacts, lower 12 pins connector. Default status is high (5 V). No. Name 1 Hold/Busy Access Activ(at)e slave, status: low master 2 Start slave 3 Reset 4 Auto zero 5 Overload always status: low 6 7 not conn. Inject marker always status: low 8 to pos. A 9 to pos. B 10 11 12 level triggered slave level triggered always level triggered Function Output: active if drift monitor ‘holds’ the run (master + slave).
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CHAPTER 6 Pulsed amperometric detection C H A P T E R 51 6 Pulsed amperometric detection Introduction Several advanced features are implemented in the DECADE. One of these features is the so-called pulse mode. In pulsed amperometric detection (PAD) the working electrode (WE) is regenerated at a frequency of 0.5 - 3 Hz by the application of a series of potential changes.
52 DECADE user manual, edition 9 The pulse mode is quite different from the DC mode: • The output signal is sampled during a fraction of the total pulse cycle. This requires electronic manipulation of the signal. Therefore, only the recorder output should be used for detection. • During the sampling time (ts) the signal generated at the WE is collected and this value is sent to the detector output. Further smoothening of the signal by means of rise time filters is not possible.
CHAPTER 6 Pulsed amperometric detection 53 chromatography. The CO2-free sodium hydroxide is available from several suppliers as a 50% solution (19.2 mol/l). NaOH pellets are not recommended because of their high CO2 content. • The accuracy of certain pH-electrodes is poor at high pH. For applications at high pH it is sometimes better to calculate the pH from the OHconcentration. • Organic modifiers (acetonitrile) strongly attenuate the signal of most carbohydrates in PAD.
54 DECADE user manual, edition 9 Optimisation of wave forms LaCourse and Johnson [2-4] have published several papers on optimisation of wave forms in PAD. Several considerations are important for the choice of the pulse duration. Optimisation is depending on the working electrode material, the sample constituents and the required detection frequency. The impression may arise that the number of variables, 3 potential steps and 4 time settings, may lead to a time-consuming optimisation procedure.
CHAPTER 6 Pulsed amperometric detection 55 of the pulse. Once every cycle, the ts signal is sent to the output. This can be visualised by magnification of a peak in the chromatogram (Fig. 19). Fig. 19. A magnified view of a chromatogram obtained with PAD. The integrator frequency is 5 times higher than the detector output frequency resulting in a typical stepwise signal.
56 DECADE user manual, edition 9 Fig. 20. A detailed part of a chromatogram acquired at different integrator frequencies. The integrator frequency is (A) 5x, (B) 2.5x, (C) 1.2x, (D) 0.6x and (E) 0.3x the frequency of the pulse. In case of PAD the duration of the pulse should also be taken in account. When the frequency of the pulse is 2 Hz, it makes no sense to acquire data on an integrator with a significantly higher frequency.
CHAPTER 6 Pulsed amperometric detection 57 different from the noble metals. The capacitance of the electrode material is very high, such that the charging current is not stabilised before start of the next potential step. This pattern makes detection impossible. Fig. 21. Change in cell current during PAD. The cell current of the noble metals gold (Au) and platinum (Pt) is stabilised faster than the cell current of glassy carbon (GC), due to a much lower capacitance of the noble metals.
58 DECADE user manual, edition 9 Table XI. Potential settings for PAD of glycols, alcohols, aldehydes at a platinum working electrode. t (ms) E (mV) s 1 2 3 20 300 +200 100 +1300 100 -100 Table XII. LC-EC conditions for PAD of carbohydrates. detector column flow rate mobile phase sample temperature flow cell REF I-cell DECADE, Antec Leyden CarboPac PA1, 4x250mm 1.0 ml/min 200 mM NaOH disaccharides 100 nmol/l, 20 µl injection 30 oC VT-03 flow cell with 3.
CHAPTER 7 Optimisation of working potential C H A P T E R 59 7 Optimisation of working potential Introduction A current - voltage (I/E) relationship, or voltammogram, characterises an analyte. It gives information on the optimum working potential, which can be used to improve detection sensitivity and selectivity. There are several ways to obtain a voltammogram. A hydrodynamic voltammogram is obtained in the DC mode by running several chromatograms at different working potentials.
60 DECADE user manual, edition 9 electrons are transferred at the WE resulting in an electrical current that is amplified by the controller. Hydrodynamic and scanning voltammogram A hydrodynamic voltammogram is constructed when the pure analyte is not available and separation over an analytical column is required.
CHAPTER 7 Optimisation of working potential 61 Fig. 24. Scanning voltammetry of 1.0 µmol/l nor epinephrine (A) at a glassy carbon working electrode, at a scan speed of 10 mV/s. Scan (B) is the blank solvent. As peak heights are used, the signal in Fig. 23, line A is only due to the analyte. The signal in Fig. 24, line A is the sum of the analyte signal and the background signal. Subtracting both lines in Fig. 24 results in a similar I/E relationship as in Fig. 23, line A.
62 DECADE user manual, edition 9 Optimisation using a voltammogram Sometimes, when interfering peaks appear in the chromatogram, it is possible to optimise the method with regard to selectivity. If the interfering compound has a higher oxidation potential, a working potential is chosen that gives the best selectivity, i.e. the largest difference in peak height. In the example of Fig. 25 the selectivity for compound X is improved considerably by decreasing the potential to E2 or E1.
CHAPTER 7 Optimisation of working potential 63 Fig. 26. At a higher pH the I/E curve of nor epinephrine is shifted to the left. Reaction kinetics predict that electrochemical detection is mass flow dependent. When the LC flow is stopped in LC-EC, the analyte will be oxidised completely and the signal decreases rapidly. This means that the flow rate not only affects temporal peak width and analysis time but also peak height. Also the background signal is sensitive towards fluctuations in the flow rate.
64 DECADE user manual, edition 9 Construction of a hydrodynamic voltammogram Before a hydrodynamic voltammogram can be obtained, the chromatographic conditions should be optimised. Then the following steps are taken: 1. A solution of the analyte at a concentration between 1 - 100 µmol/l, is prepared in mobile phase. 2. The electrochemical detector is stabilised in the DC mode at a high potential.
CHAPTER 7 Optimisation of working potential 65 Fig. 29. The scanning voltammograms of 2,4-dimethylphenol (DMP), phenol (P), 2-chlorophenol (2-CP) and 4-nitrophenol (NP). The following procedure is used to obtain the voltammograms in Fig. 24 and Fig. 29: 1. The column is removed from the LC system. The voltammogram is recorded in the flow injection analysis (FIA) mode. 2. The pure compound is dissolved in (preferably) the HPLC buffer at a concentration of ca. 10-100 µmol/l.
66 DECADE user manual, edition 9 Fig. 30. Chromatogram of the analyte plug obtained in the DC mode. Scanning takes place on top of the broad peak between 0.5 and 2.5 min after injection in FIA mode. 5. The sampling frequency of the integrator is set at 1 Hz. This is the same frequency as the voltage steps during the scan. If a higher sampling frequency is chosen a typical stepwise pattern may appear. 6. In the ‘SCAN SET’ screen an upper and a lower potential is chosen. The cycle is set at half.
CHAPTER 8 Specifications DECADE C H A P T E R 67 8 Specifications DECADE General specifications Power Operating modes Potential range Recorder output Current ranges integrator Integrator output Offset Drift monitor Event marker Auto zero RS232C Injector sensor Oven Environmental 110-120/220-240 VAC, 50/60 Hz DC, Pulse and Scan between +2.00 and - 2.00 V in 10 mV increments between +0.1 and - 0.1 or between +1.0 and -1.0 V 1 nA, 10 nA and 1 µA/V between +10.0 and -10.
68 DECADE user manual, edition 9 AUTO mode DC mode (5 files) and pulse mode (4 files), master/slave mode, cycle time, number of cycles, drift monitor Time-based control of 20 time points as to sensitivity, filter settings, output contacts (2 open collector, 2 relays), auto zero, offset, inject/load position of electrically actuated injector (option) and E-cell (DC only).
CHAPTER 9 Error messages C H A P T E R 69 9 Error messages Error Error 1 Error 2 Error 3 Error 4 Error 5 Error 6 Error 7 RECOVLD OVLD Message Current overload, maximum current + maximum compensation has been exceeded. Advise: use less sensitive range in ‘Range select’ screen. A ROM failure has been detected. Please contact supplier. A RAM failure has been detected. Please contact supplier. The system cannot detect the cell controller board. Please contact supplier.
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CHAPTER 10 Rear panel C H A P T E R 71 1 0 Rear panel TTL inputs The inputs on the lower I/O connector strip, ‘start’, ‘reset’ and ‘auto zero’ require a TTL-low pulse (minimal 100 ms) to be activated. One TTL-low pulse produces one activation, if more activations are required the next pulse must be given after 100 ms TTL-high. If the input is kept low, only one activation will result. See page 48 for detailed information on the I/O contacts.
72 DECADE user manual, edition 9 integration software or any other Windows program. The time file editor provides a well-organised spreadsheet for convenient writing of time files. Each time file provides a stepwise, time based, full parametric control with a time resolution of 1 second. Programmable parameters comprise cell potential, range, auto zero, offset, rise time, electrical injector and control of DECADE output contacts for control of external equipment.
CHAPTER 11 Troubleshooting guide C H A P T E R 73 1 1 Troubleshooting guide No detector response Possible cause No power Remedy Check line voltage setting, plug in power cord Power switch off Turn this switch ‘on’ (at the rear panel) Faulty fuse Replace fuse Divergent mains voltage Check line voltage, see page 13 Cell disconnected, or switched off Check connection Recorder/integrator disconnected Check connection Fouled WE Clean WE (see flow cell manual) High cell current Possible cause Contaminated b
74 DECADE user manual, edition 9 Possible cause Cell potential too low Contaminated buffer (high Icell) Remedy Optimise potential Replace buffer, do not recycle the buffer Baseline oscillations Possible cause Malfunctioning pump (regular pattern) Overtightened cell bolts Air bubbles in cell or REF Temperature oscillations Contaminated buffer (high Icell) Fouled WE Fe++ in buffer Remedy Check pump (seals, valves) Adjust cell bolts, check pump pressure Maintenance REF (see flow cell manual) Set oven temp
CHAPTER 12 Pulse damper C H A P T E R 75 1 2 Pulse damper The current version of the SSI pulse damper is SSI part no. 12-0625. This damper is ready for use, as supplied. The older version of the SSI damper (part no. 12-0125) is supplied with shipping screw in the full out (counterclockwise) position to provide additional space for the fluid to expand during the temperature extremes of transit.
76 DECADE user manual, edition 9 C H A P T E R 1 3 Dummy cell A successful dummy cell test confirms that the controller, including the cell cable, functions properly. If the result of the noise measurement with the dummy cell is within specs, the controller is excluded in a trouble shooting procedure. The dummy consists of a resistor (R) of 300 MOhm and a capacitor (C) of 0.47 µF in parallel.
CHAPTER 14 Index C H A P T E R 77 1 4 Index Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
78 DECADE user manual, edition 9 +24 V, I/O contact, 46 Actor, control, 20 ADD, function, 20 AUTO mode example, 37; 40 range programming, 35 AUTO, function, 20 autozero accessibility, 42 signal processing, 28 Autozero I/O contact, 44; 47 AUX1, I/O contact, 46 AUX2, I/O contact, 46 Azero, control, 20 A-ZERO, function, 20 busy output, 44 buttons DECADE keyboard, 17 capacitance WE, 55 carbohydrates chromatogram, 49 pulse settings, 55 Cell on (off), I/O contact, 44; 46 CELL=ON/OFF, function, 20 cleaning pulse
CHAPTER 14 Index DEL, function, 21 dipswitch settings, 67 drain, 13 drift monitor, 36 busy output, 44 events at t=0.00, 40 example, 38; 39 'wait...' message, 39 Drift, control, 21 dummy cell test, 74 E1, control, 22 E2, control, 22 E3, control, 22 Ec, control, 22 Ecell, status, 22 electric valve dipswitch settings, 67 inject marker trigger, 43 electrochemical reaction, 57 Eox., control, 22 Eox., status, 22 Ered., control, 22 Ered., status, 22 error messages, 67 Faraday shield, 13 File, control, 22 Filt.
80 DECADE user manual, edition 9 I/E relationship, 57 I/O contacts 0000-string TimeFile, 44 accessibility, 47 rear panel, 69 specifications, 46 I-cell display, 28 Icell, status, 23 INJ=I/L function/status, 23 inject marker trigger, 43 Inject marker example, 37 I/O contact, 47 inject/load I/O contact, 47 trigger, 43 injection valve dipswitch settings, 67 installation, 12 Tefzel/Vespel rotor, 12 installation DECADE, 11 flowcell, 14 pulse damper, 73 INT, 27 integrator connection of trigger, 37; 43 pulse mode
CHAPTER 14 Index master accessible functions, 40; 43 example, 37 maximum current, 29 maximum zero compensation, 30 messages, 67 NEXT, function, 23 noise, 14; 50; 52; 62; 65; 71 air bubbles, 14 Offs., control, 23 Offs., status, 23 offset, 29 affected by recorder range, 32 signal processing, 28 Outp.
82 DECADE user manual, edition 9 recorder ranges, 29 Range control, 24 REC, 27 recorder output, 27; 29 frequency, 52 pulse mode, 52 resolution, 29 stepwise ‘bit’ profile, 30; 35 vs.
CHAPTER 14 Index upgrade info, 20; 24; 25; 40; 41; 43; 46; 50 spare parts, 4 specifications DECADE, 65 Start I/O contact, 47 START function, 25 STATUS, function, 25 STOP, function, 25 t1, control, 25 t2, control, 25 t3, control, 25 Tefzel rotor, 50 Time, control, 26 TimeFile, 35 example, 36 interruption of, 40; 42 RS232 option, 70 step-by-step example, 38; 40 trigger started, 41 to pos.
84 DECADE user manual, edition 9 zero compensation resolution, 30 Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.
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