Rosemount SCS921A Total Chlorine Monitoring Owner's manual

Brand: Rosemount

Model: SCS921A Total Chlorine Monitoring

Type: Owner's manual

Model SCS 921A

Reagent-Based Chlorine System

Instruction Manual

PN 51-SCS921A/rev.A

November 2003

WARNING

ELECTRICAL SHOCK HAZARD

Making cable connections to and servicing

this instrument require access to shock haz-

ard level voltages which can cause death or

serious injury.

Be sure to disconnect all hazardous voltage

before opening the enclosure.

Relay contacts made to separate power

sources must be disconnected before servic-

ing.

Electrical installation must be in accordance

with the National Electrical Code

(ANSI/NFPA-70) and/or any other applicable

national or local codes.

Unused cable conduit entries must be

securely sealed by non-flammable closures

to provide enclosure integrity in compliance

with personal safety and environmental pro-

tection requirements.

The unused conduit openings need to be

sealed with NEMA 4X or IP65 conduit plugs

to maintain the ingress protection rating

(IP65).

For safety and proper performance this

instrument must be connected to a properly

grounded three-wire power source.

Proper relay use and configuration is the

responsibility of the user.

No external connection to the instrument of

more than 69VDC or 43V peak allowed with

the exception of power and relay terminals.

Any violation will impair the safety protection

provided

Do not operate this instrument without front

cover secured. Refer installation, operation

and servicing to qualified personnel.

ESSENTIAL INSTRUCTIONS

READ THIS PAGE BEFORE

PROCEEDING!

Rosemount Analytical designs, manufactures, and tests its

products to meet many national and international stan-

dards. Because these instruments are sophisticated techni-

cal products, you must properly install, use, and maintain

them to ensure they continue to operate within their normal

specifications. The following instructions must be adhered

to and integrated into your safety program when installing,

using, and maintaining Rosemount Analytical products.

Failure to follow the proper instructions may cause any one

of the following situations to occur: Loss of life; personal

injury; property damage; damage to this instrument; and

warranty invalidation.

• Read all instructions prior to installing, operating, and

servicing the product. If this Instruction Manual is not the

correct manual, telephone 1-800-654-7768 and the

requested manual will be provided. Save this Instruction

Manual for future reference.

• If you do not understand any of the instructions, contact

your Rosemount representative for clarification.

• Follow all warnings, cautions, and instructions marked on

and supplied with the product.

• Inform and educate your personnel in the proper installa-

tion, operation, and maintenance of the product.

• Install your equipment as specified in the Installation

Instructions of the appropriate Instruction Manual and

per applicable local and national codes. Connect all

products to the proper electrical and pressure sources.

• To ensure proper performance, use qualified personnel to

install, operate, update, program, and maintain the prod-

uct.

• When replacement parts are required, ensure that quali-

fied people use replacement parts specified by

Rosemount. Unauthorized parts and procedures can

affect the product’s performance and place the safe oper-

ation of your process at risk. Look alike substitutions may

result in fire, electrical hazards, or improper operation.

• Ensure that all equipment doors are closed and protec-

tive covers are in place, except when maintenance is

being performed by qualified persons, to prevent electri-

cal shock and personal injury.

WARNING

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

CAUTION

SENSOR/PROCESS

APPLICA

TION COMPATIBILITY

Wetted materials may not be compati-

ble with process composition and

operating conditions. Application

compatibility is entirely the responsi-

bility of the user.

DANGER

HAZARDOUS

AREA INSTALLATION

Installations near flammable liquids or in haz-

ardous area locations must be carefully eval-

uated by qualified on site safety personnel.

This device is not Intrinsically Safe or

Explosion Proof.

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

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 921ACase.................................................................. 5

3-1 Schematic of Sample Conditioning System and Analyzer.......................... 6

3-2 Sample Conditioning System...................................................................... 6

MODEL SCS 921A SECTION 1

DESCRIPTION AND SPECIFICATIONS

SECTION 1. DESCRIPTION AND SPECIFICATIONS

RECOMMENDED SENSOR AND ANALYZERS

SPECIFICATIONS -

SAMPLE CONDITIONING SYSTEM

PHYSICAL

Enclosure: Fiberglass reinforced polyester, designed

to NEMA 12 standards

Dimensions: H 20.6 in. W 13.3 in. D 6.9 in.

(H 52.3 cm W 33.7 cm D 17.5 cm)

Mounting: Wall

Ambient Temperature: 32° - 122°F (0 - 50°C)

Ambient Humidity: 0 - 90% (non-condensing)

Power: 115 Vac, 64 mA, 60 Hz or

230 Vac, 31 mA, 50 Hz

EMI/RFI: EN61326

LVD: EN61010-1

Weight/Shipping Weight: 13 lb/16/lb (6.0 kg/7.5 kg)

SAMPLE REQUIREMENTS

Inlet Connection: 1/4 in. tubing fitting

Drain Connections:

from flow cell: 1/4 in. tubing fitting

from flow controller: 3/4 in. barbed fitting

Inlet Pressure: <100 psig (791 kPa abs)

Flow: at least 100 mL/min

Temperature: 32° - 122°F (0 - 50°C)

Alkalinity: <125 mg/L as CaCO

SAMPLE CONDITIONING SYSTEM

Reagent: Potassium iodide, acetic acid, and sodium

acetate solution, 1 gallon (3.785 L).

Reagent Usage: 1 gallon lasts approximately 14 days.

Reagent Pump: Fixed speed peristaltic pump, 15 rpm,

10-11 mL/hr.

SPECIFICATIONS - ANALYZER

See SCS921A system product data sheet.

PERFORMANCE SPECIFICATIONS USING

MODEL 499ACL-02 SENSOR AND MODEL

1055-24 OR 54eA ANALYZER

Operating Range: 0 to 20 ppm (mg/L) as Cl

Linear Range: 0 to 6 ppm (mg/L) as Cl

Linearity: For six samples at constant temperature,

more or less evenly distributed between 0 and

6 ppm, the maximum deviation of a point from

the least squares fit to the data is less than 2% of

range.

Response Time: Following a step change, the read-

ing reaches 95% of final value within 3 minutes.

Temperature Correction: 10-35°C (50-95°F). Possible

loss of accuracy between 0 and 50°C (32 and 122°F)

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 Cl

ANALYZERS SENSOR

1055-24 or 54eA 499ACL-02-54

MODEL SCS 921A SECTION 1

DESCRIPTION AND SPECIFICATIONS

CODE SENSOR (optional selection)

30 499ACL-02-54 sensor with standard cable

31 499ACL-02-54-60 sensor with optimum EMI/RFI cable

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

MODEL

SCS921A REAGENT-BASED CHLORINE SYSTEM

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 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 - 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)

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)

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

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.

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 dechlori-

nated 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.

SECTION 2. INSTALLATION

MODEL SCS 921A SECTION 2

INSTALLATION

FIGURE 2-1. Recommended Arrangement of Analyzer and Sample Conditioning Cabinet.

The sensor is inside the cabinet.

CAUTION

The SCS921A is NOT suitable

for use in hazardous areas.

MODEL SCS 921A SECTION 2

INSTALLATION

FIGURE 2-2. Dimensions of SCS 921A Case

MILLIMETER

INCH

DWG. NO. REV.

400CL209 A

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 sam-

ple 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 mem-

brane-covered amperometric sensor in the

flow cell measures the concentration of iodine.

The analyzer (mounted outside the cabinet

holding the sample conditioning system)

receives the signal from the sensor and dis-

plays the concentration in ppm (mg/L) as Cl

The sample leaves the flow cell and drains to

waste.

Figure 3-2 shows the arrangement of components in the sample conditioning case.

SECTION 3. PRINCIPLES OF OPERATION

MODEL SCS 921A SECTION 3

PRINCIPLES OF OPERATION

FIGURE 3-1. Schematic of Sample Conditioning

System and Analyzer.

FIGURE 3-2. Sample Conditioning System

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

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.

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.

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).

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.

WARNING

Avoid contact with skin and eyes.

Wash thoroughly after using.

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 sen-

sor. 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 ana-

lyzer 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.

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.

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 retain-

er 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.

CAUTION

Pinching hazard. Keep fingers away from

pump rollers.

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 plas-

tic 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, tight-

en the metal screw below the flow controller. Replace the reagent tube and flow cell drain line.

MODEL SCS 921A SECTION 7

TROUBLESHOOTING

SYMPTOM ACTION

Sensor cannot be

zeroed.

1. Allow time for readings to stabilize, particularly after doing sensor maintenance. It may take the

sensor as long as 12 hours to stabilize.

2. Examine the membrane. Replace it if it appears to be damaged. Discard and replace the sen-

sor 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

respond to changes in

chlorine concentration or

readings are lower than

expected.

1. Verify that reagent is flowing. Remove the tube from the reagent bottle and see that air is drawn

into the tube as the pump rollers turn. Flow rate should be 10-11 mL/hr. To measure the flow rate,

see REAGENT FLOW CHECK PROCEDURE. If reagent flow is inadequate, move a fresh sec-

tion of tubing into the pump or replace the tubing. See PERISTALTIC PUMP. If the pump rotor

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

than expected.

1. Repeat calibration.

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 read-

ings 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.

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 por-

tion of the Goods/Services.

All replacements or repairs necessitated by inadequate maintenance, normal wear and usage, unsuitable power sources, unsuit-

able 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 per-

sonnel 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 peri-

od 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.

Credit Cards for U.S. Purchases Only.

The right people,

the right answers,

right now.

ON-LINE ORDERING NOW AVAILABLE ON OUR WEB SITE

http://www.raihome.com

Specifications subject to change without notice.

Emerson Process Management

Liquid Division

2400 Barranca Parkway

Irvine, CA 92606 USA

Tel: (949) 757-8500

Fax: (949) 474-7250

http://www.raihome.com

Rosemount SCS921A Total Chlorine Monitoring Owner's manual

Rosemount SCS921A Total Chlorine Monitoring Owner's manual

Rosemount SCS921A Total Chlorine Monitoring Owner's manual

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