Model 1811EL Low-Level Sodium Monitor INSTRUCTION MANUAL test values C mv slope E 0 sample values ppm ppb error stable enter/ done sample test program cal. begin cal two pt. cal. complete error add std. 1 add std. 2 PURE WATER MONITORS 1800 series release latches to access A Thermo Electron business Formerly Orion Research, Inc.
AQUAfast, Auto-ID, Cahn, EZFlash, Ionalyzer, ionplus, KNIpHE, ORION, perphect, PerpHecT, PerpHecTion, phisa, phix, phuture, Pure Water, Sage, Sensing the Future, SensorLink, Sure-Flow, TEA Analyzer, Titrator PLUS, TURBO2 and Wine Master are registered trademarks of Thermo Orion. 1-888-pHAX-ION, A +, All in One, Aplus, AQUAsnap, AssuredAccuracy, AUTO-BAR, AUTO-CAL, AUTO DISPENSER, AUTO-LOG, AUTO-READ, AUTO-STIR, Auto-Test, BOD AutoEZ, Cable-Free, CERTI-CAL, CISA, DataCOLLECT, DataPLUS, digital LogR, DirectCal, DuraProbe, Environmental Product Authority, Extra Easy/Extra Value, FAST QC, GAP, GLPcal, GLPcheck, GLPdoc, ISEasy, KAP, LabConnect, LogR, Low Maintenance Triode, Minimum Stir Requirement, MSR, NISS, No Cal, One-Touch, One-Touch Calibration, One-Touch Measurement, Optimum Results, Pentrode, phuture MMS, phuture Pentrode, phuture Quatrode, phuture Triode, Quatrode, QuiKcheK, rf link, ROSS, ROSS Resolution, SAOB, Smart CheK, Stacked, Stat Face, The Enhanced Lab, ThermaSense, Triode, TRIUMpH, Unbreakable ph, Universal Access are trademarks of Thermo Orion. Guaranteed Success and The Technical Edge are service marks of Thermo Orion. PerpHecT meters are protected by U.S. patent 4,321,544. ROSS and PerpHecT ROSS are protected by U.S. patent 4,495,050. ORION Series A meters and 900A printer are protected by U.S. patents 5,108,578, 5,198,093, D334,208 and D346,753. ORION 81, 82, 91, and 92 series glass electrodes are protected by U.S. patents 4,661,236 and 4,687,500. Sure-Flow electrodes are protected by European Patent 278,979 and Canadian Patent 1,286,720. ionplus electrodes and Optimum Results solutions have patents pending. Copyright 2002, Thermo Orion. All rights reserved. The specifications, descriptions, drawings, ordering information and part numbers within this document are subject to change without notice. This publication supersedes all previous publications on this subject.
CONTENTS General Information 1 Introduction 1 Principles of Operation 1 Principles of Calibration 2 Sample Requirements 3 Description of Model 1811EL Monitor 4 Instrument Preparation 7 Unpacking Instrument 7 Mounting, Plumbing and Wiring of Monitor 8 Electrical Wiring of Series 1800 Monitor 9 Installation of Reagent & Diffusion Tubing 10 Conditioning & Installation of New Sodium Electrode 11 Installation of New Reference Electrode 11 Installation of ATC probe 12 Flow Regulation 12 Instrument Operation 13 Description of Basic Unit Controls 13 Start-up & Normal Instrument Operation 14 Initial Instrument Set-Up 14 Use of Test Mode 15 Error Mode 15 Shutdown & Start-Up Procedure 16 Flow Off 16 Installation & Operation of Modules 17 Signal Conditioner Module 17 Removing Installed Module 17 Replacing Installed Module 17 Setting Module Output 17 Electrical Connections 18 Description of Signal Conditioner 18 Programming Measuring Range 19 Optional Alarm Module 19 Setting Alarm Output 20 Electrical Connections 21 Description of Alarm Module Controls 21 Alarm During Calibration 22 Alarm After Power Failure 22 Setting Alarms 1 and 2 22 Calibration 23 Rinsing of Flowcell 23 Double Known addition Calibration 24 Calibration at Non-Standard Concentrations 26 Span Check Procedure 26 Off-Line Calibration Procedure 27 Blank Correction Procedure 28 Instrument Maintenance 29 Maintenance Schedule 29 Weekly Maintenance 29 Monthly Maintenance 29 Bi-Monthly Maintenance 31 Yearly Preventative Maintenance 31 Troubleshooting 33 Repair and Service 37 Notice of Compliance 37 Declaration of Conformity 38 Warranty 39 Ordering Information 41 Appendix 43 Resetting Computer 43 Specifications 47 IMPORTANT NOTICE/DANGER: Current Model 1800 Series Instruments have had duck bill valves removed from flow cell manifold to prolong tubing life. As a result, power must be shut off at base of monitor before removal of reagent bottle assembly. Otherwise, the air pump will spatter caustic reagent outward as bottle is removed.
flowmeter restrictor temperature probe reference probe sensing probe calibration level pressure reducing valve flow valve calibration diverter valve measuring level bypass filter inlet valve bypass valve drain reagent addition system Figure 1: block Diagram of Sample Flow 6 5 Legend 1. inlet valve 2. bypass filter 3. pressure regulator 4. flowmeter 5. flow restrictor tubing 6. electrolyte reservoir 7. reference electrode 8. sensing electrode 9. temperature probe 11 flow cell manifold 14. reagent diffusion bottle 18. air pump 19. drain 36. flow valve 37. bypass valve 4 7 8 9 36 3 2 11 37 19 3 Figure 2: Flow Diagram Normal Operation 18 14
GENERAL INFORMATION Introduction This manual covers operation, maintenance and troubleshooting for Model 1811EL which incorporates added software features of off-line calibration and blank correction. The Thermo Orion Model 1811EL Low-Level Sodium Monitor is a microprocessor-based analyzer designed to measure continuously trace ion levels in relatively pure water. Model 1811EL Monitor measures sodium in the.01 ppb to 1000 ppb range, and has been specifically designed to operate with steam condensate, feedwater, make-up and demineralization output samples. A unique system for ph adjustment eliminates the need for expensive reagents and frequent maintenance. Instrument calibration is quick, simple, highly reliable and accurate using a simple pipet. A temperature sensor, mounted in the measuring cell, is used for automatic temperature compensation. The installed signal conditioner offers the choice between linear and logarithmic concentration output. Principles of Operation Figure 1 is a block diagram of sample flow through the monitor. Figure 2 illustrates the sample flow during normal operation. As shown in Figure 2 the sample enters the Series 1800 Monitor and passes through inlet valve, 1, bypass filter, 2, pressure regulator, 3, flow meter, 4, and restrictor tubing, 5. The sample then passes through the flow cell manifold, 11, into a reagent diffusion bottle, 14, where ph adjustment takes place. The ph adjusted sample then flows back into the flow cell manifold, 11, where air is introduced from the air line, 18, to ensure proper mixing and fast response. The sample then flows back through the flow cell manifold, 11, into an atmospheric drain, 19. The sensing electrode responds logarithmically to changes in the sodium ion concentration. This response is described by the Nernst equation: Where: E = E 0 + 2.3 (RT/nF) log (C/C iso ) E = measured electrode potential, mv E 0 = potential, when C equals C( iso ), mv R = ideal gas constant T = temperature of sample, degrees K n = valence of ionic species (+1 for sodium ion) F = Faraday s constant C = effective sodium ion concentration (activity) C iso = concentration (activity) of sodium ion where potential E is temperature independent (isopotential point) The above equation indicates that the measured potential varies with both temperature and the concentration of the ion of the interest. In order to eliminate error caused by fluctuations in sample temperature, the Series 1800 Monitor s microprocessor constantly updates temperature corrections from data supplied by the ATC probe. 1
From the Nernst equation, the theoretical response of a sodium ion-selective electrode to a ten-fold change in concentration at 25 ºC is 59.16 mv. This is referred to as the electrode slope(s). Most electrodes, however, do not exhibit a theoretical slope. Therefore, the instrument is calibrated to determine its actual value. Two standards are used to provide information necessary for the microprocessor to compute the actual slope and E 0 for use during sample analysis. In order to eliminate interference from hydrogen ions which can become significant when measuring low levels of sodium, the Model 1811EL Monitor adjusts sample ph to above 11. This ph adjustment is accomplished by the patented passive diffusion process wherein the sample passes through a tubing coil present in the reagent bottle containing aqueous amine solution which diffuses through the tube wall and redissolves, raising sample ph to about 11. Flow of sample into reservoir of flow cell is set by a combination of pressure regulator and flow restrictor tube. The pressure regulator is adjusted to give a nominal flow of 40 ml/min. The diverter valve on the flow cell is pulled out during normal operation, which maintains a sample reservoir volume of approximately 20 ml. Therefore, this system s fast response time is a result of both sample volume and flow rate. The air for mixing the sample is recirculated to eliminate potential sodium contamination from airborne salt. Principles of Calibration Double-Known Addition (DKA) Numbers refer to Figure 3. Calibration procedures for an analytical instrument are important and must be performed carefully. The patented calibration procedure used in the Model 1811EL is a variation on Double Known Addition (DKA). This method has distinct advantages when compared with conventional methods of calibration. It is fast, easy, accurate and uses a readily available pipet for calibration. The sample reservoir, as shown in Figure 1, has two sample volumes; a normal operation volume (about 20 ml) and a calibration volume (about 100mL). The lower volume results in fast system response while on-line, and the higher volume ensures accuracy in calibration. The sample diverter valve, 12, is pushed in to fill the sample reservoir to 100 ml volume prior to calibration. At this point the actual concentration in the sample is unknown but the instrument measures the potential (E s ) and stores this value in the microprocessor. A known amount of Standard Solution 1 is added to the sample reservoir which increases the concentration (C s ) with a corresponding known amount (dc 1 ). The new potential (E 1 ) is measured and stored automatically, when stability is reached. Standard 2, preferably 10 times more concentrated than Standard 1, is added which again increases the concentration (dc 2 ) in the sample reservoir. Again the new potential (E 2 ) is measured and stored when stable. Now, we have the following three unknowns: E s =E 0 + S log (C s /C iso ) E 1 =E 0 + S log [(C s + dc 1 )/C iso ] E 2 =E 0 + S log [(C s + dc 1 + dc 2 )/C iso ] E s, E 1, E 2 have been determined during the calibration procedure. The microprocessor solves these three equations giving the values of S and E 0. This data is stored for use during on-line monitoring to convert the measured potential in the sample into concentration values either in ppm or ppb. 2
Sample Requirements When the calibration is complete, diverter valve, 12, is pulled out to lower flow cell liquid level (~100 ml), to the sample measurement level (~20 ml), and flow valve, 36, is reopened. Allow about ten minutes for concentrated calibration solution to be flushed from system, then the Series 1800 Monitor can begin sample measurement. Typically, the calibration procedure takes less than 30 minutes to complete. In addition to Double-Known Addition (DKA), Model 1811EL also allows the user the ability to perform either an off-line calibration or a blank correction. Off-line Calibration The off-line calibration feature of Model 1811EL allows the user to adjust the monitor to values determined by alternate methods used in their laboratory, such as atomic absorption, ion chromatography and inductively coupled plasma. It is essentially a one-point calibration. To perform off-line calibration, a sample is taken from the bypass of the instrument; the sample value is stored in memory; the sample is analyzed by an alternate method of choice; the previously stored reading is adjusted to the lab method result; and the instrument is then returned to the analysis mode. The term off-line calibration refers only to the fact that a sample from 1811EL bypass is taken off-line for laboratory analysis; in fact, no downtime is experienced during the procedure and the instrument remains on-line throughout. Sample inlet connection 1/4 NPTF. If particulate matter is present in sample, prefiltration is necessary. Moderate amounts of particulates will be removed by the 60 micron stainless steel filter located after inlet valve. Flow rate 40 ml/min. nominal Pressure 8-100 psig. Consult Thermo Orion for details on sample handling if pressure is outside range. Temperature Temperature must be between 5-40 C. Sodium level Sodium levels are read directly in ppb or ppm, when calibrated with Thermo Orion Standards 1 and 2 (Thermo Orion Cat. No. 181140). Sample acidity Sample acidity should not be more than 50 ppm CaCO 3 equivalent. For higher sample acidity, contact the Thermo Orion Technical Service Department. CAUTION: Flow to the monitor must be turned off during regeneration of the demineralization systems and left off until most of the regeneration chemicals have been flushed out. Failure to turn off the flow may lead to a heavily contaminated flow cell. Do not allow regeneration chemicals to enter the flow cell. Blank-Correction Blank correction feature corrects deviation from a straight line Nerstian response at very low levels of sodium. The purpose of the blank correction feature is to allow adjustment of the reading to compensate for possible background effects due to either the reagent or other ions in the sample. 3
Description of Model 1811EL Monitor Numbers in the description refer to Figure 3. Sample inlet valve (1) Accepts the sample stream via 1/4 inch NPTF connector. The customer must supply the sample with a pressure between 8 and 100 psig, and a sample flow rate of 40 ml/min. nominal. Bypass filter assembly (2) 60 micron stainless steel filter traps particulate matter in sample stream. Pressure regulator (3) Adjusts flow on incoming sample stream. Flow meter (4) Measures sample flow rate. 40 ml/min. nominal flow is required. Flow restrictor tubing (5) Maintains steady sample flow rate in conjunction with pressure regulator. Electrolyte reservoir (6) Provides constant flow of electrolyte solution through reference electrode for maximum stability. Reference electrode (7) Provides a constant reference potential and completes the measurement circuit. Sodium electrode (8) Senses sodium ions in sample stream and produces an electrical potential dependent on sample concentration. Diverter valve (12) Allows sample reservoir to fill to about 100 ml during calibration procedure. While sampling, reservoir is at about 20 ml. Reagent bottle adaptor (13) connects reagent diffusion bottle to sample stream and flow cell assembly. Reagent diffusion bottle (14) contains water soluble amine which raises the sample ph to about 11. LED display (15) Provides digital readouts of concentration, temperature, millivolts and error codes. Keypad (16) Consists of five mode keys, four prompt indicator lights, two scroll keys and one key for entering data. Mode and error indicators are also incorporated on keypad. On/off switch (17) Controls all power to the electronics. Flow valve (36) Used to turn off flow to flow cell during calibration. Bypass valve (37) Used to throttle flow in bypass system. Air pump (38) Used to mix standard with sample during calibration. ATC probe (9) Measures sample temperature and inputs data to microprocessor for automatic temperature compensation (ATC). Calibration port (10) Allows introduction of standards to sample reservoir during calibration. Flow cell (11) Contains reference electrode, sample electrode, ATC probe and sample measurement reservoir. Air is bubbled through liquid to keep electrodes clean as well as to mix the sample. Both calibration and normal measurements are made in the flow cell. 4
38 6 4 7 8 9 10 36 test values C mv slope E 0 sample values ppm ppb error stable enter/ done sample test program begin two cal. cal pt. cal. complete 15 16 5 error add std. 1 add std. 2 8 11 12 2 37 13 PURE WATER MONITORS 1800 series 14 1 release latches to access 17 Figure 3: Major Components of Low-Level Sodium Monitor 5
Description of Model 1811EL (cont.) 18 22 21 7 8 9 10 11 23 13 12 7 reference electrode 8 sodium electrode 9 temperature probe 10 calibration port 11 flow cell assembly 12 diverter valve 13 bottle adapter 14 diffusion bottle 18 air line 20 reagent safety drain 21 sample drain 22 siphon tube 23 thumbscrew 20 14 Figure 4: Details of Flow Cell Assembly 6
INSTRUMENT PREPARATION Unpacking Instrument Report any obvious damage of shipping container to carrier and hold for inspection. The carrier (not Thermo Orion) is responsible for any damage incurred during shipment. 1. Open outer box. Remove foam corner support pieces. 2. Open inner box and remove cardboard retaining shell. Remove accessory boxes (4 pcs.) and instruction manual. 3. Unbolt the monitor from mounting board. 4. Carefully place the monitor at a convenient location. Do not pull or lift instrument by its fluidic components. Figure 5: Unpacking Model 1811EL 7
Mounting And Plumbing Instructions 1. Select a site for the instrument that allows it to be permanently bolted (in an upright position) with ample height for atmospheric drain operation and ready access to to both electronic controls and flow cell calibration port. A clearance of 15 inches (about 40 cm) must be allowed above the calibration port for vertical (not angled) insertion of a pipet during calibration. The analyzer location must permit connection to a plumbed in sample line, a drain, an AC power supply and any connections for output devices. 2. The analyzer should be mounted as close to the sampling point as possible, this ensures the fastest possible response to a changing sample condition. 3. Prepare mounting holes. Carefully lift the analyzer and bolt into place. Do not lift the instrument by holding on to any of the plumbing or fluid handling components. 4. Connect a waste line to a drain of sufficient capacity, 0.5 inch (1.27cm) OD is recommended). 4. All electrical wiring feeding through the chassis of the cabinet must pass through appropriate electrical fittings in order to maintain the design integrity of the splash proof cabinet housing the analyzer electronics. As different types of fittings may be required at various installations, this feed through is to be supplied by the user. WARNING: A grounded metal conduit is required for FCC compliance. 5. Replace the protective plastic front panel when complete. WARNING: Failure to replace the protective plastic front panel will result in a potential shock hazard. NOTE: 1800 Series monitors made prior to 1997 used different wiring connections. Please contact Thermo Orion Service Department for the correct schematic for these older models. 5. Connect sample line to the 0.25 inch (0.635 cm) NPTF stainless steel inlet. It is recommended that a shut of valve be installed at the sampling point. Electrical Connection Instructions 1. Remove the protective plastic, front panel inside the cabinet by unscrewing the 4 holding screws. Remove the protective plastic plug at the bottom of the cabinet and feed the AC power line through the hole. 2. Set voltage (from underside of analyzer) to either 115V or 230V (factory default setting is 115V). 3. Connect AC power according to wiring diagram. Figure 6. 8
Electrical Wiring of Series 1800 Monitor NOTE: 1800 Series monitors made prior to 1997 used different wiring connections. Contact thermo Orion Service Department for correct schematic for these older models. Input wiring connections are different than previous models. 1. IMPORTANT: Review safety precautions described in MOUNTING, PLUMBING and WIRING of 1800 SERIES MONITOR as described in manual. 2. Connect sample line to the 0.25 inch (0.635 cm) NPTF stainless steel inlet. It is recommended that a shut of valve be installed at the sampling point. 3. Switch voltage selector to either 115 or 230 VAC depending on input power. 4. Connect power according to diagram. See Figure 6. Additional Requirements For C.E. Compliance: Failure of the cord insulation in a cord anchorage which has metal parts shall not cause ACCESSIBLE conductive parts to become HAZARDOUSLY LIVE. A compression bushing shall not be used as a cord anchorage unless it has provisions for clamping all types and sizes of main supply cords which meets the requirements of 6.10.1 and are suitable for connection to the terminals provided or the bushing has been designed to terminate a screened supply cord. The cord anchorage shall be designed so that cord replacement does not cause a hazard and it shall be clear how the relief from strain is provided. Cutaway Drawing Showing Bottom Interior of 1800 Series Electronics Enclosure (Blue) Common Line in (Brown) Hot Line in Cord Anchorage The cord anchorage shall relieve the conductors of the cord from strain and twisting, where they are connected within the equipment. It must also protect the insulation of the conductors from abrasions. The protective earth conductor, if any, shall be the last to take the strain if the cord slips in its anchorage. AC Power Inlet Ground Green/Yellow Line In Cord anchorage shall meet the following requirements: The cord shall not be clamped by a screw which bears directly on the cord. Power ON/OFF (Switched from Underside of Instrument) Knots in the cord shall not be used. It shall not be possible to push the cord into the equipment to an extent which could cause a hazard. Voltage Selector (115V/230V) (Switched from Underside of Instrument) Figure 6: Electrical Wiring of Series 1800 Monitor 9
Installation of Reagent and Diffusion Tubing WARNING: Monoethylamine is hazardous. Use protective glasses and gloves. Refer to bottle label for precautions. 1. Remove thumbnut. 23, of bottle adaptor, 13, and slide adaptor/reagent bottle assembly from instrument. 2. Unscrew cap, 24, and lift adaptor from bottle. Fit ends of diffusion tubing, 27, over bottle adaptor nipples, 25. 3. In hood (or outdoors) carefully remove cap on reagent bottle. 4. Verify there is an O-ring, 26, between the bottle adaptor and bottle. Slide diffusion tubing loops into reagent bottle and screw adaptor into full reagent bottle. NOTE: Adaptor may be rotated in bottle to allow for correct positioning, so that bottle label faces to the front. 5. Check that all three O-rings, 28, are in place on flow cell assembly face, 11. Mount bottle adaptor/reagent assembly to flow cell by sliding onto screw stud and tightening nut, 23. 24 11 28 23 13 25 26 14 27 Figure 7: Reagent Bottle Assembly 10
Conditioning & Installation of New Sodium Electrode New Cat. No. 100048 sodium electrode must be used. Note that 100048 can only be used in conjunction with new 100058 reference electrode. WARNING: Safety glasses must be worn during entire conditioning procedure. Gloves must be worn when using etch solution. WARNING: Only sodium sensing electrode is etched. Do not etch reference electrode. 1. Unpack sodium electrode (Cat. No. 100048) and carefully remove protective cap. Save cap for future storage of electrode. 2. Immerse sodium electrode in bottle of etch solution (Cat. No. 181113) for one minute. 3. Remove and rinse with deionized water. Wipe bulb with clean lab tissue paper. Rinse again. 4. Insert sodium electrode into sensing hole of flow cell cap. See Figure 4. Sensing electrode is placed in the hole to the right of the divider seen in flow cell and the hole closest to the electronics cabinet. 5. Connect electrode to cable marked Sens. Elect. 6. Wait at least one hour before calibrating analyzer. Installation of New Reference Electrode To further improve the performance of the Model 1811EL, the reference electrode filling solution has been upgraded to 0.1M CsBr (Cat. No. 150072). The new catalog number for the reference electrode with one 2-oz. bottle 150072 fill solution is 100058. This electrode is unique and cannot be interchanged with other reference electrodes when used on Model 1811EL. Note that 100048 sodium and 100058 reference electrodes must be used together. 1. Unpack reference electrode, 7, (Cat. No. 100058) and tubing from shipping box. Remove protective caps from bottom and sidearm of electrode. Save caps for future storage of electrode. Inspect internal chamber of electrode (item 7 in Figure 8). Verify it is at least half filled with the internal fill solution. If not, replace the electrode. 2. While passing 1/8-inch tubing, 31, into electrode through sidearm, slide 1/4-inch tubing, 32, over sidearm. The outside tubing should extend 3/8-1/2-inch over sidearm. 3. Remove cap and fluid seal from electrolyte fill solution bottle, 33. Hold bottle in upright position. Check that rubber gasket, 34, is properly aligned, then connect cap end of tubing assembly to bottle. The 1/8-inch tubing should extend into the bottle, and into the sidearm of the electrode. 4. Hold reservoir above electrode with bottle cap end down. Electrode should be horizontal with sidearm pointing up. Gently shake electrode to allow any trapped air bubbles to rise into bottle as electrode fills with solution. 5. Dry off ceramic frit on base of electrode with tissue paper. Squeeze bottle for a few seconds. A small amount of filling solution should bead up on frit surface, indicating good electrolyte flow. If no moisture is visible, electrode is clogged and should be replaced. 11
Installation of ATC Probe 35 The automatic temperature compensation (ATC) probe is already connected to the electronics housing. Insert into remaining hole of flow cell cap. 33 34 31 32 30 7 Figure 8: Reference Electrode Assembly 6. Invert electrolyte bottle and snap into clip, 35. Use push pin supplied to puncture three air vents on bottom of bottle. Flow Regulation When the Model 1811EL Monitor is first commissioned, it is advisable to flush out fluidics system overnight prior to initial calibration and use. The electronics need not be turned on at this time. Refer to Figure 3. 1. Open sample inlet valve, 1. 2. Pull out the black knob of pressure regulator, 3, then adjust knob so that ball of flow meter reads 40 ml/min. Push in knob to secure the setting if desired. 3. Push in diverter valve, 12. This allows flow cell to fill to calibration volume. The system will continuously fill and siphon. 4. Open bypass valve, 37. Check for appropriate sample flow. Readjust pressure regulator if required. 5. Wait at least one hour before calibrating analyzer. CAUTION: Failure to vent electrolyte bottle will lead to noisy and drifty meter readings. 7. Connect electrode to cable labeled ref. Electrode. Insert electrode into reference hole in flow cell cap. See Figure 4. Reference electrode should be placed in hole located closest to the calibration port in Figure 4. 12
INSTRUMENT OPERATION Description of Basic Unit Controls On/off switch Controls power to all electronics and air pump. It is located on electronic chassis bottom and includes an integral circuit breaker. LCD display Displays four-and-one-half digit plus polarity sign used to read concentration, slope, E 0, millivolts, temperature, error messages, and diagnostic information. Mode indicating LED (Located to left of LCD display.) Indicates range (ppb or ppm), error codes, and electrode stable in sample mode. Displays temperature (ºC), millivolts, electrode slope, and E 0 on LCD in test mode. Error If error LED is lit (soft error), then pressing key causes LCD to display an error code. Note, in the case of hard error, LCD would cease to display normal output but would display error code only. Refer to Error Code Table. Program key Used to program expected dc1, dc2 calibration concentration increments and flow cell volume. Also used in conjunction with Cal key for off-line calibration and blank correction procedures. Prompt indicating LED Prompts the user during calibration. Four LED s located in keypad region are used. These are: fill/flow off; add STD1; add STD 2; drain/flow on. and keys Increases or decreases displayed values that can be operator-changed such as alarm level, analog output range, off-line calibration, and blank correction values. test values C mv slope E 0 sample values ppm ppb error stable enter/ done Caution Removal of front panel will expose hazardous voltage. Attention En retirant le panneau avant vous vous exposez a une tension electrique dangereuse. Enter/done key Enters value displayed on LCD into permanent memory for later use. Key also indicates to microcomputer that a required calibration step has been completed. Sample key Puts Series 1800 Monitor into sample mode and (re) activates any optional modules. This is also its default mode, e.g., instrument automatically enters sample mode when first turned on and after calibration. sample test program cal. error begin cal. add std. 1 two pt. cal. complete add std. 2 Figure 9: Front Panel Keypad Cal key Starts Series 1800 Monitor into calibrate mode. Operator is then prompted through the steps necessary for calibration. Test key Places Series 1800 Monitor into test mode where LCD displays temperature, millivolts, E 0 and slope. Each successive push of key, steps instrument through this sequence, and an LED on the left of display indicates value displayed. 13
Start-Up & Normal Instrument Operation 1. Install the Model 1811EL Monitor according to instructions in Instrument Preparation. Power supply should be wired for proper voltage and instrument suitably grounded. 2. Turn on flow at sample inlet and flush for at least one hour. 3. Power up Model 1811EL by toggle switch on bottom of electronics case. See Figure 3. 4. Observe air bubbling through liquid in flow cell. LCD will display following information sequence: a. + 1.8.8.8.8; b. 18EL while LEDs sequentially light; NOTE: Mode indicating LEDs and test LED on modules are not tested during start-up sequence. c. Revision number of software program (e.g., -1.1-) 5. After completion of steps 1-4, the Monitor is now in normal operational mode sample. Initial Instrument Set-Up Before first sample measurements on Model 1811EL can be performed, calibration concentration increments and flow cell volume must be programmed into memory. Table 1 Revised Program Key Table Code Meaning P0 Off-line calibration value P1 Blank correction value P2 Concentration increase for STD 1 addition (20 ppb) P3 Concentration increase for STD 2 addition (200 ppb) P4 Flow cell volume (95 ml ± 5) NOTE: PROGRAM KEY TABLE has been revised on Model 1811EL to simplify customer interface if use of off-line calibration and/or blank correction feature is desired. New Program Key Table is found on inside of instrument door and below. P2 and P3 values shown are based on use of Standard 1 and Standard 2 as found in Cat. No. 181140. 1. Press program key five times until LCD displays P4 (flow cell volume variable) for two seconds, then the current value for flow cell volume will be displayed. Default value is 95 ml. Actual value printed on flowcell. 2. Change this value by using keys marked and. When display reads correct value, press enter/done key. Volume has been stored in instrument memory. Note that programmed volume value should correspond to that stamped on side of flow cell. This P4 value will need to be updated if the flow cell is replaced. 3. Press program key until LCD displays P2 (20 ppb unless different standards are used). Then the current value for the first concentration increment will be displayed. Default value is 20 ppb. 4. Change this value by using keys marked and. Press enter/done key to store appropriate value in memory. Note P2 cannot exceed the P3 value. 5. Press program key until the LCD displays P3 (200 ppb unless different standards are used) for two seconds. Then the current value for the second concentration increment will be displayed. Default value is 200 ppb. 6. Change this value by using and. Press enter/done key to store appropriate value in memory and unit will automatically return to sample mode. If no values have been changed, press sample key to exit program mode. 7. Battery backup of memory will maintain programmed variables for at least one month if battery is fully charged. NOTE: When choosing P2 and P3, calculate using a flow cell volume of 95 ml. The microprocessor automatically corrects the programmed values of P2 and P3 for the actual flow cell volume (P4). 14
Use of Test Mode When test key is pressed, the LCD displays temperature, millivolts, slope and E 0. Every time the test key is pressed the monitor steps through this sequence. An LED to the left of display indicates value displayed. If test mode is entered from sample mode, then sample and test LED are lit. If test mode is entered from calibration mode, then calibrate and test LED are lit. Note that while LCD displays test information, the instrument still continues normal sampling or calibration sequence. Therefore, when sample and test modes are pressed, signal conditioning and optional alarm modules are active. When calibrate and test modes are pressed, calibration prompt LEDs will light as usual. To exit test mode press sample or calibrate key as desired. LCD will now display instantaneous computed concentration. If sample key is pressed while in the calibration mode, the current calibration will abort with no data saved. Error Mode The Model 1811EL Monitor diagnoses two types of errors which are termed hard and soft. In the event of hard error, the analyzer cannot compute any meaningful concentration values, error LED will be lit and LCD will display an error code. The signal conditioner module will indicate zero scale and alarms will be deactivated. Hard error must be corrected prior to resumption of normal operation (E40 and E50) by performing a complete calibration. If error LED is active but instrument continues to display concentration, this is termed soft error. Soft error can affect accuracy and/or precision of displayed concentration but not interfere with instrument s ability to compute sample concentration. To determine cause of soft error, press error key and LCD will display error code. Table 2 Error Codes Error Code Meaning E00 E01 E02 E03 E04 E05 E10 E20 E30 E40 E50 No errors Default values are used. The monitor has not been calibrated since start-up or the reset button was pushed. Sample is outside the temperature range of 5-45 C Combination of E01 and E02 Faulty ATC probe, or related circuitry Combination of E01 and E04 After calibration the new slope is outside expected range Calibration due. Last calibration performed 30 days ago. A reminder to perform another calibration. Calibration due and slope error. This indicates that the last calibration was performed at least 30 days ago and the electrode slope was out of specification at that time. Calibration overdue. It has been at least 6 weeks since the last calibration. The instrument beyond this point could be out of specification. This is a hard error. The only way to exit this error is to perform a complete DKA or off-line calibration. (Blank will not affect this error code.) Calibration is overdue and slope error. This indicates that it has been at least 6 weeks since the last calibration and the electrode slope was out of specification at that time. The instrument beyond this point could be out of specification. This is a hard error. The only way to exit this error is to perform a complete DKA or off-line calibration. (Blank correction will not affect this error code.) 15
Start-up The most common error codes are combinations of the above codes, but other errors may be displayed: E12 E14 E21 E22 E10 and E02 E10 and E04 E20 and E01 E20 and E02 Shutdown and Start-up Procedure The following steps should be taken if a loss of sample flow is expected for more than one day. These procedures will prevent possible build-up of caustic reagent vapors in the analyzer. Shutdown DANGER: Shut off power switch at base of monitor before beginning procedure; otherwise, the air pump will spatter caustic reagent outward as bottle is removed. 1. Shut off sample flow prior to the analyzer inlet. 2. Turn off power. 3. Drain flow cell. WARNING: Wear rubber gloves and safety goggles to avoid possible injury from reagent residues in the system. 4. Remove reagent bottle and store in a well ventilated area such as a laboratory fume hood. 1. Replace the diffusion tubing if sample flow has been off for more than a few days. Tubing becomes brittle with long term exposure to reagent. Use a fume hood and wear rubber gloves and safety goggles for this procedure. If age of reagent is not known, replace it and note in maintenance records. Re-install bottle on analyzer. 2. Etch sodium electrode for one minute with rinse solution (Cat. No. 181113) per instruction manual procedure, rinse with deionized water, and carefully re-install on analyzer. 3. Restore sample flow to analyzer. If necessary, adjust pressure and flow rate through analyzer to normal ranges. 4. Remove protective end cap from reference electrode. Re-install electrode on analyzer being careful not to disconnect reservoir tubing from sidearm. 5. When meter reading stabilizes (about one hour), recalibrate according to Calibration section. Flow Off If the analyzer is expected not to have flow for time periods of less than twenty-four (24) hours, leave the instrument on and neglect its output. If the time is expected to be greater than twentyfour (24) hours, follow Shutdown procedures. 5. Carefully pull sodium and reference electrodes out of the top of the flow cell and let them hang by their connectors. Locate protective end cap from reference electrode kit and place on base of reference electrode. This will prevent the reference electrode from drying out. 16
INSTALLATION AND OPERATION OF MODULES Signal Conditioner (Cat. No. 180001) The Model 1811EL Monitor is shipped with signal conditioner module (Cat. No. 180001) factory installed. Read section Setting Module Output and if you need to change the factory settings, see Removing Installed Module. When factory settings are correct for your instrument then proceed to section Electrical Connections Signal Conditioner Module. Removing Installed Module 1. Ensure power to the Series 1800 Monitor is turned off at power source. 2. Unscrew module keypad from the black brackets using the two screws on the keypad. 3. Make certain the black plastic plungers are pulled back so that the grommets are in a closed position. 4. Slide out module far enough to access DIP switches Replacing Installed Module 1. Ensure power to the Series 1800 Monitor is turned off at power source. 2. Open door of electronic assembly. Use No. 2 Phillips screwdriver to remove screws on decorative panel. alter preset output values before sliding the module into the monitor, as follows (also refer to Table 3). 1. Current output, factory set at 4-20 ma. 0-20 ma is obtained when switching S1-2 into OFF position and S1-3 into ON position. 2. Voltage output, factory set at 0-5V DC. 0-10V DC is obtained when switching S1-1 into ON position. 3. Slide PC Board onto instrument guide rails. Rear of PC Board should touch backplane and plug should fit securely into its socket. Check that module bracket is against both rails. 4. Push plungers in. 5. Make certain flex cable is attached to keypad and to PC Board. If not, carefully slide header into socket. Screw module keypad back onto frame. Table 3 Signal Conditioner Output Modes S1-1 S1-2 S1-3 S1-4 0-5 V OFF X* X X 0-10 V ON X X X 4-20 ma X ON OFF X 0-20 ma X OFF ON X * X means no effect 3. Remove module keypad from shipping box. 4. Unscrew module keypad from the black brackets using the two screws on the keypad. 5. Make certain the plungers are pulled back so that the grommets are in a closed position. 1 2 3 4 6. Proceed to section Setting Module Output. Setting Module Output The signal conditioner has two voltage outputs (0-5 or 0-10 volts) and two current outputs (4-20 or 0-20 ma isolated). Switches are preset by manufacturer at 0-5 volts and 4-20 ma but can be reset by DIP switch (see Figure 10) on signal conditioner printed circuit board. When required, Figure 10: Dip Switches on Signal Conditioner PC Board 17
Electrical Connections 1. If module keypad is still attached, then unscrew module keypad from black brackets using the two screws on the keypad. 2. Feed wire through hole in chassis bottom labeled option. See Figure 6. 3. Run wire along wire trough to signal conditioner. 4. Connect wires to voltage (0-5V or 0-10V) or current (0-20 ma or 4-20 ma) output. See Table 4. 5. Double check the flex cable connections. 6. Screw the keypad on the black metal brackets. 7. Double check the flex cable connections. 8. Measure to ensure appropriate number of panels has been removed. 9. Align decorative panel against four stand-offs and reattach with Phillips screws. Decorative panel should not cover any optional module. Description of Signal Conditioner Set zero Sets lower level concentration output. In this mode LED above set zero is active. To set output to either linear or logarithmic, hold key down to toggle between these output forms. Set full scale Sets upper level concentration output. In this mode LED above set full scale is active. Test Generates zero or full scale output to set up an external recording device. Test key deactivates signal conditioner module and either set zero or full scale LED will be active. After pressing test key, there will be an output delay of up to three seconds. Press sample key to reactivate module. Mode indicating LED (located on left module keypad). Indicates linear or logarithmic signal output. When set zero key is held, the mode toggles between these output forms. WARNING: For safety reasons, the Series 1800 Monitor should not be operated without the decorative panel in place. Failure to replace the panel could expose the user to dangerous voltages. Table 4 Outputs of Signal Conditioner Panel Output Voltage (+) 1 (-) 2 Current (-) 7 (+) 8 Terminals 1 2 3 4 5 6 7 8 Figure 12: Signal Conditioner Module NC NC NC NC + + 0 to 5V DC or 0 to 10V DC Output 1K W Load Min. 0 ma to 20 ma or 4 ma to 20 ma Current Output 1K W Load Min. log output linear output test set zero set full scale Figure 13: Signal Conditioner Keypad Figure 11: Description Of Signal Conditioner 18
Programming Measuring Range 1. Press set zero key. LED above set zero will activate and LCD will display current programmed value. Preset default value is 0.1 ppb for log range and 0.1 ppb for linear range. 2. Alter value by using and keys. Lowest possible value is 0.01 ppb. 3. Press enter/done key when the correct value is displayed. 4. Set upper range by pressing set full scale then follow above procedure. Preset default value is 100 ppb. Note that it is not possible to set zero value higher than full scale, and a range of at least two decades should be used. 5. To send 0% and 100% of full scale signal to an external recording device, press test key on signal conditioner module. The first time causes 0% signal to be sent, the second time causes full scale signal. Remember there may be up to a three second delay when test key is pressed. 6. To alternate from log to linear mode: Press and hold the set zero key. The output mode will toggle between log and linear, indicated by the LED. Release the set zero key when in desired mode. Table 5 Default Values Model 1811EL P0 Off-line CAL Value 000 P1 Blank Correction Value 000 P2 (dc1) STD 1 20.00 ppb P3 (dc2) STD 2 200 ppb P4 (Volume) 95.0 Set Zero (log) 0.10 ppb Set Zero (linear) 0.10 ppb Set Full Scale (log) 100 ppb Set Full Scale (linear) 100 ppb Set Alarm 1 100 ppb Set Alarm 2 1.00 ppm Slope 59.2 mv -25.0 mv E 0 Optional Alarm Module (Cat. No. 180011) The 1800 Series alarm circuit is unique. If instrument logic detects sodium concentration is increasing at such a rate that high alarm value will be reached within an hour, a warning signal is activated. This signal is a one second alarm every four seconds, which increases in frequency as concentration approaches alarm level. Also, if absolute sodium concentration is 90% of high alarm value, an intermittent warning signal is activated to alert operator that high concentration limit is being approached. If this feature is not desired, the low alarm can be used to set external alarm. Alarms are rated at 10A, 250V. Installation The optional module is mounted in the instrument in the following manner: 1. Ensure power to the Model 1811EL Monitor is turned off at power source. 2. Open door of electronic assembly. Use No. 2 Phillips screwdriver to remove four screws on decorative panel. 3. Remove optional module keypad assembly from shipping box. 4. Unscrew module keypad from the black brackets using the two screws on the keypad. 5. Make certain the plungers on the black metal frame are pulled back so that the grommets are in a closed position. 6. Slide PC board onto guide rails, and push back into socket. 7. Push plastic plungers in. Table 6 Terminals 7 and 8 Alarms Disabled Mode NO NC Jumper E7 to E8 (factory set) E6 to E8 19
Setting Alarm Output For both alarms 1 and 2, NO and NC conditions are available simultaneously. For alarms disabled condition, either NO (factory set) or NC is available. To change factory setting, remove module ( as described in last section), and perform the following steps: 2. Place PC Board (See Figure 15) onto instrument guide rails. Rear of PC Board should touch backplane and plugs should fit securely into its socket. Check that module bracket is against both rails. Press the two plastic plungers down to lock module in place. 1. Solder the appropriate jumper, to change between the NO and NC mode for an alarms disabled remote indication (terminals 7 and 8). (See Figure 14). Guide Rail Socket Guide Rail E6 E7 E8 7 8 Figure 15: Alarm Module Figure 14: Jumper Connections On Alarm Module PC Board 3. Make certain flex cable is attached to keypad and to PC Board. If not, carefully slide header into socket. 20
Electrical Connections for Alarm Module 1. Feed wire through hole in chassis bottom. 2. Run wire along wire trough to alarm module. 3. Connect output wires as required. See Table 7. 4. Double check the flex cable connections. 5. Screw the keypad on the black metal brackets. 6. Double check the flex cable connections. 7. Measure to ensure appropriate number of panels have been removedfrom protective cover. 8. Align protective cover decorative panel against four stand-offs and re-attach with Phillips screws. Protective cover should not obscure any optional module. WARNING: For safety reasons, the Series 1800 Monitor should not operate without the protective cover in place. Failure to replace the cover could expose the user to dangerous voltages. Table 7 Outputs of Alarm Module Terminals Outputs Alarm 1 Comm 1 NC 2 NO 3 Alarm 2 Comm 4 NC 5 NO 6 Disable Comm 7 NO/NC 8 Terminals Description of Alarm Module Controls Set alarm 1 Sets alarm 1 parameter. When set alarm 1 is pressed, LED on key is active. See Table 5 for default values. Set alarm 2 Sets alarm 2 parameter. When set alarm 2 is pressed, LED key is active. See Table 5 for default values. Test Activates and deactivates alarm 1 and 2 and deactivates relays. Test LED will be lit along with corresponding mode key. To reactivate module, press sample key on front panel keypad. Mode indicating LED (located to left of keypad.) Indicates if either alarm goes off. If alarms are not active, deactivated LED blinks; for example, during calibration. For both alarms, the LED indicating activation is on whenever concentration is above set point. Since each alarm output has only normally open and normally closed position, any external alarm can be set to go off when concentration is either above or below the set point. NOTE: The corresponding LED for either alarms turns on when the concentration exceeds the set point. Simultaneously, the relay closes and the NO position closes. alarm one alarm two deactivated alarm module test alarm set alarm one alarm two Figure 17: Alarm Module Keypad 1 2 3 4 5 6 7 8 NC NO ALARM 1 Alarm contacts 10A 250VAC max NC NO ALARM 2 Alarm contacts 10A 250VAC max NC E6 E8 E7 NO Disable output contacts Choose either NC or NO contacts 10A 250VAC max Figure 16: Wiring Diagram of Alarm Module 21
Alarm During Calibration During calibration the alarm module is automatically deactivated. After the completion of calibration the Series 1800 Monitor automatically enters the sample mode, however, the alarm module remains deactivated. To reactivate, press sample key. The alarm module is deactivated to avoid the high concentration alarm that would result from the standards used to calibrate. Alarm After Power Failure After a power failure, the alarm module remains deactivated until sample key on the front panel keypad (see Figure 9) is pressed. The alarm settings are not affected by power provided for remote indication. Setting Alarms 1 and 2 Alarm limits work on 5 decade ranges only. For example if an alarm is set to 1.0 ppb, the alarm will go off at 1.0 ppb and will continue to remain on until the 100 ppm value is reached. Anything above the 5 decade range will turn the alarm off. 1. Press set alarm 1 key. LED above set alarm 1 will activate and LCD will display present alarm value. 2. Change displayed value by use of and keys. 3. Press enter/done key when correct value is displayed. Alarm 1 value is now set. 4. Press set alarm 2 key. LED above set alarm 2 will activate and LCD will display present alarm 2 value. 5. Change displayed value by use of and keys. 6. Press enter/done key when correct value is displayed. Alarm 2 value is now set. 7. If an external alarm circuit is to be tested, press test key. The first press of the test key deactivates both alarms, second press activates alarm 1, and third press activates alarm 2. Press sample key to exit test mode. 22