Reagent-Based Chlorine System

Instruction Manual PN 51-SCS921A/rev.A November 2003 Model SCS 921A

Reagent-Based Chlorine System ESSENTIAL INSTRUCTIONS WARNING ELECTRICAL SHOCK HAZARD READ THIS PAGE BEFORE Making cable connections to and servicing PROCEEDING! this instrument require access to shock hazard level voltages which can cause death or Rosemount Analytical designs, manufactures, and tests its serious injury. products to meet many national and international standards. Because these instruments are sophisticated techni- Be sure to disconnect all hazardous voltage cal products, you must properly install, use, and maintain before opening the enclosure. them to ensure they continue to operate within their normal specifications. The following instructions must be adhered Relay contacts made to separate power to and integrated into your safety program when installing, sources must be disconnected before servic- using, and maintaining Rosemount Analytical products. ing. Failure to follow the proper instructions may cause any one of the following situations to occur: Loss of life; personal Electrical installation must be in accordance injury; property damage; damage to this instrument; and with the National Electrical Code warranty invalidation. (ANSI/NFPA-70) and/or any other applicable • Read all instructions prior to installing, operating, and national or local codes. servicing the product. If this Instruction Manual is not the Unused cable conduit entries must be correct manual, telephone 1-800-654-7768 and the securely sealed by non-flammable closures requested manual will be provided. Save this Instruction Manual for future reference. to provide enclosure integrity in compliance with personal safety and environmental pro- • If you do not understand any of the instructions, contact tection requirements. your Rosemount representative for clarification. The unused conduit openings need to be • Follow all warnings, cautions, and instructions marked on sealed with NEMA 4X or IP65 conduit plugs and supplied with the product. to maintain the ingress protection rating • Inform and educate your personnel in the proper installa- (IP65). tion, operation, and maintenance of the product. For safety and proper performance this • Install your equipment as specified in the Installation instrument must be connected to a properly Instructions of the appropriate Instruction Manual and grounded three-wire power source. per applicable local and national codes. Connect all products to the proper electrical and pressure sources. Proper relay use and configuration is the responsibility of the user. • To ensure proper performance, use qualified personnel to install, operate, update, program, and maintain the prod- No external connection to the instrument of uct. more than 69VDC or 43V peak allowed with • When replacement parts are required, ensure that quali- the exception of power and relay terminals. fied people use replacement parts specified by Any violation will impair the safety protection Rosemount. Unauthorized parts and procedures can provided affect the product’s performance and place the safe oper- Do not operate this instrument without front ation of your process at risk. Look alike substitutions may cover secured. Refer installation, operation result in fire, electrical hazards, or improper operation. and servicing to qualified personnel. • Ensure that all equipment doors are closed and protective covers are in place, except when maintenance is being performed by qualified persons, to prevent electri- WARNING cal shock and personal injury. This product is not intended for use in the light indus- trial, residential or commercial environment, per the instrument’s certification to EN50081-2.

Emerson Process Management Rosemount Analytical Inc. 2400 Barranca Parkway Irvine, CA 92606 USA Tel: (949) 757-8500 Fax: (949) 474-7250 http://www.raihome.com

DANGER CAUTION

HAZARDOUS AREA INSTALLATION SENSOR/PROCESS APPLICATION COMPATIBILITY Installations near flammable liquids or in haz- Wetted materials may not be compati- ardous area locations must be carefully eval- ble with process composition and uated by qualified on site safety personnel. operating conditions. Application This device is not Intrinsically Safe or compatibility is entirely the responsi- Explosion Proof. bility of the user. To secure and maintain an intrinsically safe installation, the certified safety barrier, transmitter, and sensor combination must be used. The installation system must com- ply with the governing approval agency (FM, CSA or BASEEFA/CENELEC) hazardous area classification requirements. Consult your analyzer/transmitter instruction manual for details. Proper installation, operation and servicing of this device in a Hazardous Area Instal- lation is entirely the responsibility of the user.

About This Document

This manual contains instructions for installation and operation of the Model SCS921A Reagent-Based Chlorine System.

The following list provides notes concerning all revisions of this document.

Rev. Level Date Notes A 11/03 This is the initial release of the product manual. The manual has been reformatted to reflect the Emerson documentation style and updated to reflect any changes in the product offering. MODEL SCS 921A TABLE OF CONTENTS

MODEL SCS 921A REAGENT-BASED CHLORINE SYSTEM

TABLE OF CONTENTS Section Title Page 1.0 DESCRIPTION AND SPECIFICATIONS...... 1 Specifications...... 1 Ordering Information...... 2

2.0 INSTALLATION...... 4 Unpacking and Inspection ...... 4 Installation...... 4

3.0 PRINCIPLES OF OPERATION ...... 6

4.0 START-UP ...... 7 Install the Sensor ...... 7 Install the Sample and Drain Lines ...... 7 Connect the Sample Conditioning Cabinet to a Power Source ...... 7 Start Sample Flow...... 7 Zero the Sensor ...... 8 Prepare and Install the Reagent ...... 8 Begin Operation...... 8

5.0 CALIBRATION ...... 9

6.0 MAINTENANCE AND TROUBLESHOOTING...... 10 Inspection ...... 10 Sample Conditioning Reagent ...... 10 Peristaltic Pump...... 10 Sensor ...... 10 Reagent Flow Check Procedure...... 11 Cleaning the Sample Conditioning System ...... 11 Troubleshooting ...... 12

i MODEL SCS 921A TABLE OF CONTENTS

TABLE OF CONTENTS CONT'D.

LIST OF FIGURES Figure No. Title Page 2-1 Recommended Arrangement of Analyzer & Sample Conditioning Cabinet . 4 2-2 Dimensions of SCS 921A Case ...... 5 3-1 Schematic of Sample Conditioning System and Analyzer ...... 6 3-2 Sample Conditioning System...... 6

ii MODEL SCS 921A SECTION 1 DESCRIPTION AND SPECIFICATIONS

SECTION 1. DESCRIPTION AND SPECIFICATIONS

The SCS 921A is a sample conditioning and measuring system for the continuous determination of chlorine in water. Although the SCS921A is intended primarily for the determination of chlorine in chlorinated seawater, it can also be used to determine monochloramine, free chlorine, and certain bromine oxidants. It is not suitable for the determination of dichloramine and other inorganic and organic chloramines. The conditioning system continuously pumps buffered potassium iodide reagent into the sample. Oxidants in the sample convert iodide into an equivalent amount of iodine. A sensor measures the concentration of iodine and sends its signal to the analyzer. The analyzer displays the concentration in ppm (mg/L) as Cl2.

SPECIFICATIONS - SAMPLE CONDITIONING SYSTEM SAMPLE CONDITIONING SYSTEM Reagent: Potassium iodide, acetic acid, and sodium PHYSICAL acetate solution, 1 gallon (3.785 L). Enclosure: Fiberglass reinforced polyester, designed Reagent Usage: 1 gallon lasts approximately 14 days. to NEMA 12 standards Reagent Pump: Fixed speed peristaltic pump, 15 rpm, Dimensions: H 20.6 in. W 13.3 in. D 6.9 in. 10-11 mL/hr. (H 52.3 cm W 33.7 cm D 17.5 cm) Mounting: Wall Ambient Temperature: 32° - 122°F (0 - 50°C) SPECIFICATIONS - ANALYZER Ambient Humidity: 0 - 90% (non-condensing) See SCS921A system product data sheet. Power: 115 Vac, 64 mA, 60 Hz or 230 Vac, 31 mA, 50 Hz EMI/RFI: EN61326 PERFORMANCE SPECIFICATIONS USING LVD: EN61010-1 MODEL 499ACL-02 SENSOR AND MODEL Weight/Shipping Weight: 13 lb/16/lb (6.0 kg/7.5 kg) 1055-24 OR 54eA ANALYZER Operating Range: 0 to 20 ppm (mg/L) as Cl2. SAMPLE REQUIREMENTS Linear Range: 0 to 6 ppm (mg/L) as Cl2. Inlet Connection: 1/4 in. tubing fitting Linearity: For six samples at constant temperature, Drain Connections: more or less evenly distributed between 0 and from flow cell: 1/4 in. tubing fitting 6 ppm, the maximum deviation of a point from from flow controller: 3/4 in. barbed fitting the least squares fit to the data is less than 2% of range. Inlet Pressure: <100 psig (791 kPa abs) Response Time: Following a step change, the read- Flow: at least 100 mL/min ing reaches 95% of final value within 3 minutes. Temperature: 32° - 122°F (0 - 50°C) Temperature Correction: 10-35°C (50-95°F). Possible Alkalinity: <125 mg/L as CaCO3 loss of accuracy between 0 and 50°C (32 and 122°F)

RECOMMENDED SENSOR AND ANALYZERS ANALYZERS SENSOR 1055-24 or 54eA 499ACL-02-54 1 MODEL SCS 921A SECTION 1 DESCRIPTION AND SPECIFICATIONS

ORDERING INFORMATION AND ACCESSORIES Model SCS921A Reagent-Based Chlorine System. The SCS921A is used for the continuous determination of chlorine in seawater. It can also be used to measure the sum of monochloramine and free chlorine in water. The SCS921A con- sists of a sample conditioning system, a sensor, and an analyzer. Reagents must be ordered separately. See ACCES- SORIES - Sample Conditioning System.

MODEL SCS921A REAGENT-BASED CHLORINE SYSTEM CODE POWER (required selection) 11 115 V 60 Hz 12 230 V 50 Hz

CODE ANALYZER (optional selection) 250 1055-01-10-24 analyzer, panel mount 251 1055-01-11-24 analyzer, pipe/wall mount 260 54eA-01 analyzer 261 54eA-01-09 analyzer with HART communications 262 54eA-01-20 controller with PID and TPC control 263 54eA-01-09-20 controller with PID and TPC control and HART communications

CODE SENSOR (optional selection) 30 499ACL-02-54 sensor with standard cable 31 499ACL-02-54-60 sensor with optimum EMI/RFI cable

2 MODEL SCS 921A SECTION 1 DESCRIPTION AND SPECIFICATIONS

ACCESSORIES - Sample Conditioning System PN DESCRIPTION WEIGHT* SHIP WEIGHT* 9380080 Peristaltic pump for reagent, 115 Vac, 60 Hz 2 lb (1.0 kg) 2 lb (1.0 kg) 9380086 Peristaltic pump for reagent, 230 Vac, 50 Hz 2 lb (1.0 kg) 2 lb (1.0 kg) 23868-00 Replacement tubing for peristaltic pump, 6 ft 1 lb (0.5 kg) 2 lb (1.0 kg) 9380087 Retainer disk for peristaltic pump tubing 1 lb (0.5 kg) 2 lb (1.0 kg) 9100132 Fuse, 1/8 A, Slo-blo, 3AG 250V, for 115 Vac version 1 lb (0.5 kg) 2 lb (1.0 kg) 9100191 Fuse, 1/16 A, Slo-blo, 3AG 250V, for 230 Vac version 1 lb (0.5 kg) 2 lb (1.0 kg) R459-4GAL Reagent, acetic acid/acetate buffer with potassium iodide, 4 x 1-gal bottles/case 38 lb (17.5 kg) 40 lb (18.5 kg)

ACCESSORIES - 1055-24 Analyzer

PN DESCRIPTION WEIGHT* SHIP WEIGHT* 9240048-00 Tag, stainless steel, specify marking 1 lb (0.5 kg) 1 lb (0.5 kg) 23820-00 Pipe mounting kit 2 lb (1.0 kg) 3 lb (1.5 kg) 23554-00 Gland fitting PG 13.5, 5 per package 1 lb (0.5 kg) 1 lb (0.5 kg)

ACCESSORIES - 54eA Analyzer

PN DESCRIPTION WEIGHT* SHIP WEIGHT* 2002577 Wall and two inch pipe mounting kit 2 lb (1.0 kg) 3 lb (1.5 kg) 23545-00 Panel mounting kit 2 lb (1.0 kg) 3 lb (1.5 kg) 23554-00 Cable glands, kit (Qty 5 of PG 13.5) 1 lb (0.5 kg) 1 lb (0.5 kg) 9240048-00 Stainless steel tag (specify marking) 1 lb (0.5 kg) 1 lb (0.5 kg)

ACCESSORIES - Sensor

PN DESCRIPTION WEIGHT* SHIP WEIGHT* 23501-02 Total Chlorine Membrane, includes one membrane assembly and one O-ring 1 lb (0.5 kg) 1 lb (0.5 kg) 23502-02 Total Chlorine Membrane Kit, includes 3 membrane assemblies and three O-rings 1 lb (0.5 kg) 1 lb (0.5 kg) R434-4OZ Total Chlorine Sensor Fill Solution, includes electrolyte and KI crystals to be 1 lb (0.5 kg) 2 lb (1.0 kg) mixed before use (discard excess after use)

*Weights are rounded up to the nearest whole pound or 0.5 kg.

3 MODEL SCS 921A SECTION 2 INSTALLATION SECTION 2. INSTALLATION

UNPACKING AND INSPECTION Inspect the shipping containers. If there is damage, contact the shipper immediately for instructions. Save the boxes. If there is no apparent damage, unpack the containers. Be sure all items shown on the packing list are pres- ent. If items are missing, notify Rosemount Analytical immediately.

INSTALLATION.

CAUTION The SCS921A is NOT suitable for use in hazardous areas.

See Figure 2-1. Install the grab sample point as close as possible to the sample line supplying the SCS 921A. Be sure that opening the grab sample valve does not appreciably alter the flow of sample to the instrument. If the SCS 921A is measuring dechlorinated water, provide a way of substituting a chlorinated water sample for the dechlorinated sample. Chlorinated water is needed to calibrate the sensor and to check its response. Be sure the sample conditioning cabinet is level and the sample drains to open atmosphere. Back pressure on both drains must be absent. See Figure 2-2 for the dimensions of the sample conditioning system cabinet. See the analyzer instruction manual for analyzer dimensions and mounting instructions.

FIGURE 2-1. Recommended Arrangement of Analyzer and Sample Conditioning Cabinet. The sensor is inside the cabinet.

4 MODEL SCS 921A SECTION 2 INSTALLATION

MILLIMETER INCH

DWG. NO. REV. 400CL209 A

FIGURE 2-2. Dimensions of SCS 921A Case

5 MODEL SCS 921A SECTION 3 PRINCIPLES OF OPERATION SECTION 3. PRINCIPLES OF OPERATION

See Figure 3-1. The sample enters a constant head flow controller, which provides a flow of about 100 mL/min to the sensor. Excess sample leaves the flow controller through the inner drain tube. To ensure correct flow, sample must continuously be flowing down the inner tube. From the outlet of the flow controller, the sample enters the mixing block where the reagent is injected. The reagent, which is a solution of potassium iodide in an acetic acid/acetate buffer, converts halogen oxidants in the sample into an equivalent amount of iodine. The treated sample next flows through a static mixer and into the flow cell. A membrane-covered amperometric sensor in the flow cell measures the concentration of iodine. The analyzer (mounted outside the cabinet holding the sample conditioning system) FIGURE 3-1. Schematic of Sample Conditioning receives the signal from the sensor and dis- System and Analyzer. plays the concentration in ppm (mg/L) as Cl2. The sample leaves the flow cell and drains to waste. Figure 3-2 shows the arrangement of components in the sample conditioning case.

FIGURE 3-2. Sample Conditioning System

6 MODEL SCS 921A SECTION 4 START-UP SECTION 4. START-UP

See Figure 3-1 and Figure 3-2.

INSTALL THE SENSOR 1. From inside the cabinet, thread the sensor cable through the gland on the upper-left side. Leave about one foot of cable inside the cabinet. Remove the protective cap from the end of the sensor. 2. Wrap the sensor threads with pipe tape. Remove the nut and adapter from the flow cell. Slip the nut over the sensor and thread the adapter onto the sensor. Hand tighten only. 3. Place the sensor in the flow cell. Hand-tighten the nut. 4. Wire the sensor to the analyzer. See the sensor and analyzer instruction manuals for details.

INSTALL THE SAMPLE AND DRAIN LINES 1. Connect the sample line to the 1/4 in. tubing connection at the base of the flow controller. 2. Attach a short drain line to the 1/4 in. tubing connection at the bottom of the cabinet and to the 3/4” barbed fitting at the bottom of the flow controller. The drains must empty into a receiver open to atmosphere. See Figure 2-1.

CONNECT THE SAMPLE CONDITIONING CABINET TO A POWER SOURCE

WARNING: RISK OF ELECTRICAL SHOCK AC connections and grounding must be in compliance with UL 508 or local electrical code. DO NOT apply power to the analyzer until all electrical connections are verified and secure.

1. Provide a switch or breaker to disconnect the unit from the main power supply. Install the switch or breaker near the unit and label it as the disconnecting device for the analyzer. 2. Be sure power switch in sample conditioning cabinet is off. 3. Connect the sample conditioning unit to the AC power source.

START SAMPLE FLOW 1. Adjust the sample flow so that a stream of liquid continuously runs down the inside tube of the flow controller. 2. Verify that sample is flowing through the sensor flow cell and draining to waste.

7 MODEL SCS 921A SECTION 4 START-UP

ZERO THE SENSOR 1. Place the reagent tube in a container of water or leave in air. 2. Turn the power switch on. The peristaltic pump will start. 3. Let the system run until the sensor current is stable. See the analyzer manual for instructions on how to dis- play the sensor current. It may take as little as two hours or as long as overnight for the reading to stabilize. 4. Zero the analyzer. See the analyzer manual for details.

PREPARE AND INSTALL THE REAGENT 1. Add the potassium iodide crystals (PN R-459A) to the gallon bottle of buffer solution (PN R-459S).

WARNING Avoid contact with skin and eyes. Wash thoroughly after using.

2. Cap the bottle and invert several times to mix. 3. Insert the reagent tube in the reagent bottle and screw the cap in place. Place the bottle in the cabinet. Secure the bottle with the strap. Close the cabinet door. NOTE The shelf life of the potassium iodide - buffer solution is about fifteen days. DO NOT PREPARE THE SOLUTION UNTIL READY TO USE. The reagent is unstable in sunlight. Keep the cabinet door closed.

BEGIN OPERATION 1. Once the flow of reagent starts, it takes about one minute for the sensor current to begin to increase. If the concentration of chlorine is more than about 0.5 ppm, the treated sample will be pale yellow. 2. Monitor the sensor current. Once the reading is stable, calibrate the unit. It may take an hour or longer for the reading to stabilize. See the analyzer manual for detailed instructions.

8 MODEL SCS 921A SECTION 5 CALIBRATION SECTION 5. CALIBRATION

Calibrate the system when the sensor membrane is replaced or when other maintenance is performed on the sensor. Check the calibration of the system every time the sample conditioning reagent is replaced. Calibrate by making the analyzer reading match the total chlorine level determined in a grab sample. See the analyzer instruction manual for details. See Figure 2-1 for suggested placement of the grab sample point. Be sure that opening the grab sample valve does not appreciably change the flow to the sample conditioning system.

9 MODEL SCS 921A SECTION 6 MAINTENANCE AND TROUBLESHOOTING SECTION 6. MAINTENANCE AND TROUBLESHOOTING

INSPECTION. Periodically inspect tubing for cracks and leaks. Replace tubing if it appears to be damaged. Tubing downstream from the reagent injection point turns yellow after a few days in service.

SAMPLE CONDITIONING REAGENT. The sample conditioning reagent lasts about fifteen days. Do not mix the potassium iodide crystals in the small bottle (PN R-459A) with the acetate buffer in the large bottle (PN R-459S) until ready to use. The reagent should be colorless after mixing and should remain colorless for its life.

PERISTALTIC PUMP. 1. The tubing inside the pump becomes worn with usage. Pull a new section of tubing into the pump every two months. There is six feet of extra tubing on the suction (left hand) side of the pump. a. Remove the clear plastic cover.

CAUTION Pinching hazard. Keep fingers away from pump rollers.

b. Slide the plastic retainer on the suction side of the tubing away from the pump about four inches (10 cm). c. While the pump is running, pull the four inches (10 cm) of tubing through the pump head until the retainer is snug against the pump head. d. Slide the retainer on the discharge side of the tubing toward the pump until it is about 3/4 inch (20 mm) from the bottom of the pump head. e. Replace the cover. 2. To replace pump tubing: a. Turn off the power. b. Remove the clear plastic cover. c. Remove the two screws holding the pump cover in place and lift off the cover. d. Pull the old tubing from between the pump shroud and rollers. e. Detach the old tubing from the reagent tube and from the fitting at the mixing tee. f. Slip off the retainer discs. g. Prepare one end of the new tubing to feed through the holes in the retainer discs. Stretch the tubing and hold it against a flat surface with the thumb and forefinger. Cut the stretched tubing using a straight-edged razor blade held almost parallel to the tubing. h. Pass the tapered end of the tubing through the discs. i. Pull the discs along the tubing until they are about one foot (30 cm) from the tapered end. Pull the retainer disc furthest from the end an additional five inches (13 cm) from the end. Cut the tapered end flat. j. Insert the length of tubing between the retainer discs between the shroud and rollers. Be sure the long end of the tubing is on the suction (left hand) side of the pump. Slide the retainer disc on the suction side until it is snug with the bottom of the pump. Slide the retainer disc on the discharge side until it is about 3/4 inch (20 mm) from the bottom of the pump head. k. Replace the pump cover and fasten it with the two screws. l. Thread the ends of the tubing through the two holes in the clear plastic cover and snap the cover in place. m. Attach the long end of the tubing to the reagent tube and attach the short end to the fitting at the mixing tee.

10 MODEL SCS 921A SECTION 6 MAINTENANCE AND TROUBLESHOOTING

REAGENT FLOW CHECK PROCEDURE 1. Turn the pump off. 2. Remove the tubing from the reagent bottle. 3. Mark off two inches (51 mm) from the bottom of the tubing. 4. Let the tubing hang in air with the end even with the bottom of the reagent bottle. 5. Start the pump and verify that it takes between 40 and 50 sec for the meniscus to reach the 2-in. (51-mm) mark.

CLEANING THE SENSOR Suspended solids in the sample slowly accumulate on the membrane. Wash the membrane every month with a stream of water from a wash bottle.

CLEANING THE SAMPLE CONDITIONING SYSTEM The sample conditioning system can disassembled for cleaning 1. Turn off power to the reagent pump. 2. Stop the sample flow and allow the flow cell and flow controller to drain. 3. Remove the sensor from the flow cell and store it with the membrane immersed in a beaker of water. 4. Disconnect the reagent tubing at the mixing block. 5. Disconnect the flow cell drain tube at the elbow leaving the flow cell. 6. A screw on the outside of the enclosure just below the constant head flow controller holds the mixing tee to the flow controller. Remove the screw. 7. Pull the mixing block and flow cell from the plastic fitting connecting it to the flow controller. 8. Unscrew the plastic screw at the end of the mixing block. 9. Use a stiff wire to push the static mixer out of the mixing block. To avoid jamming the mixer in the screw threads, push it out through the other end. 10. Unscrew the flow cell from the mixing block. 11. Use a strong stream of water to flush out solids. If necessary, a small brush or pipe cleaner can also be used to remove solids. 12. Reassemble the sample conditioning system. Push the static mixer into the mixing block and replace the plastic screw. Screw the flow cell back into the mixing block. Push the mixing block and flow cell onto the plastic fitting from the flow controller. While holding the mixing block tight against the inside wall of the enclosure, tighten the metal screw below the flow controller. Replace the reagent tube and flow cell drain line.

11 MODEL SCS 921A SECTION 7 TROUBLESHOOTING

TROUBLESHOOTING

SYMPTOM ACTION Sensor cannot be 1. Allow time for readings to stabilize, particularly after doing sensor maintenance. It may take the zeroed. sensor as long as 12 hours to stabilize. 2. Examine the membrane. Replace it if it appears to be damaged. Discard and replace the sensor electrolyte. 3. Check sensor for open and short circuits. See the sensor manual for details. 4. Verify that the sensor is correctly wired to the analyzer. Analyzer does not 1. Verify that reagent is flowing. Remove the tube from the reagent bottle and see that air is drawn respond to changes in into the tube as the pump rollers turn. Flow rate should be 10-11 mL/hr. To measure the flow rate, chlorine concentration or see REAGENT FLOW CHECK PROCEDURE. If reagent flow is inadequate, move a fresh sec- readings are lower than tion of tubing into the pump or replace the tubing. See PERISTALTIC PUMP. If the pump rotor expected. is not turning, check the fuse. Replace the pump if necessary. 2. Verify that the water level in the flow controller is even with the top of the inside drain tube and that a stream of liquid is continuously running down the tube. 3. Check the flow rate of the sample leaving the flow cell. It should be between about 80 and 120 mL/min. If the flow is much below 80 mL/min, readings will be low. Normally, loss of flow is caused by obstructions building up the in the reagent mixing block. If solids are being trapped in the static mixer, it can be removed. Removing the static mixer reduces mixing efficiency and leads to a moderate increase in noise. See CLEANING THE SAMPLE CONDITIONING SYS- TEM for instructions. 4. Examine the membrane. It may be coated. If it is, rinse the membrane with water or replace it. See the sensor manual for details. 5. Verify that the sensor is correctly wired to the analyzer. 6. Repeat calibration. Readings are higher 1. Repeat calibration. than expected. 2. Check that reagent is clear and colorless. If it is pale yellow, results will be high. To prevent the reagent from turning yellow, protect it from sunlight by keeping the cabinet door closed.

Readings are erratic. 1. A new sensor usually takes time to stabilize. Readings should be stable after several hours although it may take as long as 12 hours. 2. Verify that all wiring connections are tight. 3. Check the sensor membrane. If it is loose or damaged, replace it. 4. Mixing may be incomplete. Verify that the static mixer is in place.

Readings drift. 1. Verify that the water level in the flow controller is even with the top of the inside drain tube and that a stream of liquid is continuously running down the tube. 2. Check the flow rate of the sample leaving the flow cell. It should be between about 80 and 120 mL/min. If the flow is much below 80 mL/min, readings will be low. Normally, loss of flow is caused by obstructions building up the in the reagent mixing block. If solids are being trapped in the static mixer, it can be removed. Removing the static mixer reduces mixing efficiency and leads to a moderate increase in noise. See CLEANING THE SAMPLE CONDITIONING SYS- TEM for instructions. 3. Verify that reagent is flowing. Remove tube from the reagent bottle and see that air is being drawn into the tube as the pump rollers turn.To measure flow rate, see REAGENT FLOW CHECK PROCEDURE. 4. Drift can be caused by sudden changes in sample temperature. Following a step change readings will drift for about 10 minutes while the sensor reaches sample temperature. 5. Mixing may be incomplete. Verify that the static mixer is in place.

12 WARRANTY Seller warrants that the firmware will execute the programming instructions provided by Seller, and that the Goods manufactured or Services provided by Seller will be free from defects in materials or workmanship under normal use and care until the expira- tion of the applicable warranty period. Goods are warranted for twelve (12) months from the date of initial installation or eighteen (18) months from the date of shipment by Seller, whichever period expires first. Consumables, such as glass electrodes, membranes, liquid junctions, electrolyte, o-rings, catalytic beads, etc., and Services are warranted for a period of 90 days from the date of shipment or provision. Products purchased by Seller from a third party for resale to Buyer ("Resale Products") shall carry only the warranty extended by the original manufacturer. Buyer agrees that Seller has no liability for Resale Products beyond making a reasonable commercial effort to arrange for procurement and shipping of the Resale Products. If Buyer discovers any warranty defects and notifies Seller thereof in writing during the applicable warranty period, Seller shall, at its option, promptly correct any errors that are found by Seller in the firmware or Services, or repair or replace F.O.B. point of man- ufacture that portion of the Goods or firmware found by Seller to be defective, or refund the purchase price of the defective portion of the Goods/Services. All replacements or repairs necessitated by inadequate maintenance, normal wear and usage, unsuitable power sources, unsuitable environmental conditions, accident, misuse, improper installation, modification, repair, storage or handling, or any other cause not the fault of Seller are not covered by this limited warranty, and shall be at Buyer's expense. Seller shall not be obli- gated to pay any costs or charges incurred by Buyer or any other party except as may be agreed upon in writing in advance by an authorized Seller representative. All costs of dismantling, reinstallation and freight and the time and expenses of Seller's personnel for site travel and diagnosis under this warranty clause shall be borne by Buyer unless accepted in writing by Seller. Goods repaired and parts replaced during the warranty period shall be in warranty for the remainder of the original warranty period or ninety (90) days, whichever is longer. This limited warranty is the only warranty made by Seller and can be amended only in a writing signed by an authorized representative of Seller. Except as otherwise expressly provided in the Agreement, THERE ARE NO REPRESENTATIONS OR WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, AS TO MERCHANTABILITY, FIT- NESS FOR PARTICULAR PURPOSE, OR ANY OTHER MATTER WITH RESPECT TO ANY OF THE GOODS OR SERVICES.

RETURN OF MATERIAL

Material returned for repair, whether in or out of warranty, should be shipped prepaid to:

Emerson Process Management Liquid Division 2400 Barranca Parkway Irvine, CA 92606

The shipping container should be marked: Return for Repair Model ______

The returned material should be accompanied by a letter of transmittal which should include the following information (make a copy of the "Return of Materials Request" found on the last page of the Manual and provide the following thereon):

1. Location type of service, and length of time of service of the device. 2. Description of the faulty operation of the device and the circumstances of the failure. 3. Name and telephone number of the person to contact if there are questions about the returned material. 4. Statement as to whether warranty or non-warranty service is requested. 5. Complete shipping instructions for return of the material.

Adherence to these procedures will expedite handling of the returned material and will prevent unnecessary additional charges for inspection and testing to determine the problem with the device.

If the material is returned for out-of-warranty repairs, a purchase order for repairs should be enclosed. The right people, the right answers, ON-LINE ORDERING NOW AVAILABLE ON OUR WEB SITE right now. http://www.raihome.com

Specifications subject to change without notice.

Credit Cards for U.S. Purchases Only.

Emerson Process Management Liquid Division 2400 Barranca Parkway Irvine, CA 92606 USA Tel: (949) 757-8500 Fax: (949) 474-7250 http://www.raihome.com