Instruction Manual

C 114Multiparameter

Turbidity &Free and Total Chlorine

This Instrument is in Compliance with the CE Directives

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MAN

C114R

112/03

PRINTED INC

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Dear Customer,Thank you for choosing a Hanna Product.Please read this instruction manual carefullybefore using the instrument.This manual will provide you with the necessaryinformation for the correct use of the instrument,as well as a precise idea of its versatility. If youneed more technical information, do not hesi-tate to e-mail us at tech@hannainst.com.This instrument is in compliance with direc-tives EN 50081-1 and EN 50082-1.

TABLE OF CONTENTS

Preliminary Examination ............................. 3

General Description .................................... 4

Principle of Operation .................................. 6

Functional Description ................................. 9

Specifications ............................................ 12

Operational Guide ..................................... 13

Calibration ................................................. 19

Diagnostic mode ....................................... 27

Logging with C 114 .................................... 28

User-selectable Shutdown ......................... 30

Battery Replacement ................................ 31

Diagnostic Codes ...................................... 32

Accessories .............................................. 33

Warranty ................................................... 34

CE Declaration of Conformity .................... 35

CE DECLARATION OF CONFORMITY

Recommendations for UsersBefore using this product, make sure that it is entirely suitable for the environment inwhich it is used.

Operation of this instrument in residential areas could cause unacceptable interfer-ence to radio and TV equipment, requiring the operator to take all necessary steps tocorrect the interference.

Any variation introduced by the user to the supplied equipment, may degrade the instrument's EMCperformance.

To avoid electrical shocks, do not use this instrument when voltage at the measurement surfaceexceeds 24VAC or 60VDC.

To avoid damage or burns, do not perform any measurement in microwave ovens.

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PRELIMINARY EXAMINATION

Remove the instrument from the packing ma-terial and examine it to make sure that nodamage has occurred during shipping. If thereis any damage, notify your Dealer.

C114 is supplied complete with:• 1.5V AA Size Batteries (4 ea.)• Glass Cuvet• Cap

In addition to the above items, an optionalstarter kit HI 731327 is available, suppliedwith:

• Measurement cuvets (2 pcs)• Primary calibration standards:

HI 93102-0 AMCO-AEPA-1 0 NTU* cali-bration solution, 30 mLHI 93102-20 AMCO-AEPA-1 20 NTU* cali-bration solution, 30 mL

• HI 93703-50 Cleaning solution, 230 mL• HI 731318 Tissue for wiping the cuvets

(4 pcs)• HI 710031 Rugged carrying case

Note: Save all packing material until you aresure that the instrument functions cor-rectly. Any defective item must be re-turned in its original packaging withthe supplied accessories.

* 1 NTU (Nephelometric Turbidity Unit) = 1 FTU(Formazine Turbidity Unit)

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WARRANTY

All Hanna Instruments meters are warrantedfor two years against defects in workmanshipand materials when used for their intendedpurpose and maintained according to instruc-tions. This warranty is limited to repair orreplacement free of charge. Damages due toaccidents, misuse, tampering or lack of pre-scribed maintenance are not covered.If service is required, contact the dealer fromwhom you purchased the instrument. If underwarranty, report the model number, date ofpurchase, serial number and the nature of thefailure. First obtain a Returned Goods Authori-zation number from the Customer Service de-partment, then return the instrument with theAuthorization # included along with shipmentcosts prepaid. If the repair is not covered by thewarranty, you will be notified of the charges.When shipping any instrument, make sure it isproperly packaged for complete protection.To validate your warranty, fill out and return theenclosed warranty card within 14 days from thedate of purchase.All rights are reserved. Reproduction in wholeor in part is prohibited without the writtenconsent of the copyright owner.

GENERAL DESCRIPTION

The Hanna C114 is a portable microproces-sor driven, multiparameter instrument. Themeter measures Free & Total Chlorine andTurbidity.

In the colorimetric mode, the user can selecteither factory preprogrammed calibration set-tings or calibrate the meter using customizedcalibration values based on the concentrationor relative absorbance of the sample. Calibra-tion data is also stored in a non-volatileEEPROM.

In the turbidity mode, periodic recalibration ofthe meter with primary standards accordingto regulatory requirements or personal experi-ence is suggested. Turbidity ranges are 0.00-9.99 NTU and 10.0-50.0 NTU.

C114 complies with G.L.P. Standards (GoodLaboratory Practice), that is:• When switched on, the LCD displays all

segments (display check).• Battery status is monitored during every

measurement cycle warning the user if thebatteries become weak.

• It utilizes a real time clock and recallscalibration data such as date, time andcalibration values.

To facilitate field tests, the meter provides alogging mode. In this mode, the user canstore up to twenty five time-tagged measure-ments in RAM and scroll the memory at anytime.

There are eight keys for the different opera-tional modes. The large Liquid Crystal Dis-play is dual-level: the upper level has fourdigits and can display the measured param-eter in hundredths. The lower level has three

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* 1 NTU = 1 FTU.

ACCESSORIES

HI 710031 Rugged carrying caseHI 731318 Tissue for wiping the cuvets

(4 pcs)HI 731327 Starter kit includes:

Rugged carrying case;HI 93102-0 AMCO-AEPA-10 NTU* calibration solution,30 mL;HI 93102-20 AMCO-AEPA-120 NTU* calibration solution,30 mL;HI 93703-50 Cleaning solution,230 mL;HI 731318 Tissues for wipingthe cuvet (4 pcs);Two measurement cuvets

HI 93102-0 AMCO-AEPA-1 0 NTU* cali-bration solution, 30 mL

HI 93102-20 AMCO-AEPA-1 20 NTU* cali-bration solution, 30 mL

HI 93701-01 Reagents for 100 Free Chlo-rine tests

HI 93701-03 Reagents for 300 Free Chlo-rine tests

HI 93703-50 Cleaning solution, 230 mLHI 93711-01 Reagents for 100 Total Chlo-

rine testsHI 93711-03 Reagents for 300 Total Chlo-

rine tests

characters and indicates current mode (e.g.F CL for free chlorine or TR for turbidity).Different LCD segments indicate low battery,logging mode, date, time, etc.

A pure Green LED has been utilized as alight source for both turbidimetric and colori-metric measurements. A silicon photocell isused to receive transmitted light from colori-metric channel while another photocell re-ceives scattered light from the turbidimetric(nephelometric) channel.

In order to measure chlorine parameters, allthe operator has to do is zero the blanksample and then add 1 packet of reagent.After placing the cuvet back in the meter andpressing READ, the measurements are showndirectly on the LCD.

The instrument operates with four AA batter-ies and may be operator-programmed to turnitself off automatically after 10, 20, 30, 40, 50or 60 minutes of inactivity.

C 114 and all accessories such as samplevials, reagent pillows, primary standards, canbe easily stored in the optional carrying case(HI 710031).

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DIAGNOSTIC CODES

LOBAT Weak batteries. Change all batter-ies as soon as possible.

-BA- Exhausted batteries. Change allbatteries immediately.

-LO- Low level of light is received duringthe zeroing procedure.Check for scratches on the cuvetand ensure that sample is not ex-cessively turbid. Repeat the read-ings. If the problem persists,recalibrate the meter using deion-ized water in the diagnostic mode“31” (see Calibration).

-CAP- Light intensity is high during lastmeasurement. Make sure the cuvetis capped and placed properly inthe holder, and that ambient lightdoes not reach the photodetector.Repeat the measurement. If theproblem persists, contact your dealeror the nearest Hanna Office.

Er 1 Hardware error. Repeat the mea-surement. If the error message ap-pears again, contact your dealer orthe nearest Hanna Office.

rnG Out of range. Check the measuringprocedure and verify theconcentration of the sample toensure that is not too high.

PRINCIPLE OF OPERATION

Turbidity Mode

C 114 has been designed to perform mea-surements according to the USEPA’s 180.1method and the Standard Method 2130B.The instrument functions by passing a beamof light through a vial containing the samplebeing measured.The light source is a Pure Green LED toensure that any interference caused by acolored samples is minimized.A sensor, positioned at 90° with respect tothe direction of light, detects the amount oflight scattered by the undissolved particlespresent in the sample. The microprocessorconverts such readings into NTU* values.

NTU units are equal to FTU units. However,there are other known measurement units forturbidity, namely the Jackson Turbidity Unit(JTU) based on the old method of Jackson'scandle, and Silica Unit (mg/L of SiO2). Theconversion table between these measurementunits is shown below:

JTU NTU/FTU SiO2 (mg/L)

JTU 1 19 2.5

NTU/FTU 0.053 1 0.13

SiO2 (mg/L) 0.4 7.5 1

* 1 NTU = 1 FTU6 31

BATTERY REPLACEMENT

A “LOBAT” indicationappears on the lowerright hand side of thedisplay when the bat-teries are weak and require replacement. Atthis point the instrument is still able to per-form approximately 50 additional measure-ments.A “-BA-” indication willappear on the displaywhen the batteries aretoo weak to performaccurate measurements. This message ap-pears for a few seconds and then the meterwill completely switch itself off. At this pointthe batteries must be replaced.Batteries should onlybe replaced in a safearea using 1.5V AA al-kaline type.In order to replace thebatteries, simply re-move the two screwson the rear cover of theinstrument and replaceall four 1.5V AA batter-ies with new ones,while paying attentionto their polarity.

The meter will store new settings in its non-volatile memory and the display will flash“CAL” and “Stor” alternately for several sec-onds.

Colorimetric Mode

The color of every object we see is deter-mined by a process of absorption and emis-sion of the electromagnetic radiation (light) ofits molecules.Colorimetric analysis is based on the principlethat specific compounds react with others toform a color, the intensity of which isproportional to the concentration of thesubstance being measured.

Block diagram of an ion specific measurement

When a substance is exposed to a beam oflight intensity I

o, a portion of the radiation is

absorbed by the substance's molecules anda radiation of intensity I, lower than I

o, is

emitted.The quantity of radiation absorbed is given bythe Lambert-Beer Law:

log Io/I = ελ c d

Where log Io/I = Absorbance (A)

ελ = molar extinction coefficient of thesubstance at wavelength λ

c = molar concentration of thesubstance

d = optical distance light travelsthrough the sample

Since other factors are known, the concen-tration "c" can be calculated from the colorintensity of the substance determined by theemitted radiation I.An LED (Light Emitting Diode) emits radiationat a relatively narrow spectrum, supplying thesystem with the intensity I

o.

LED

EMITTED LIGHT

CUVET MICROPROCESSOR

LIGHTDETECTOR

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USER-SELECTABLE SHUTDOWN

With C 114, the users can customize theshutdown time to savepower.To change the shut-down time, enter the di-agnostic mode by momentarily pressing theALT and CAL keys together.Select mode 10 and press the key repeat-edly to set the desired shutdown time from10 to 60 minutes with 10 minute increments,or disable the shutdown mode by choosing

the OFF selection.After the selection iscompleted, exit the di-agnostic mode by pressing ALT+CAL together.

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To clear the buffer, pressthe ALT and CAL keys.Select mode 40. Press the key. The dis-play will show the “Cln” message, indicatingthat memory is being cleaned.

The lot number will be reset to 00 automatically.

REVIEWING THE CURRENT LOT NUMBERTo check the current(vacant) lot number,while in log mode,press ALT and to-gether.

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A substance absorbs a color complimentaryto the color it emits. For example, asubstance appears yellow because it absorbsblue light. As a result, the Hanna meters useLED’s with specific wavelengths to measuresamples.The optical distance (d) is measured by theinternal diameter of the cuvet containing thesample.The photoelectric cell collects the radiation Ithat is not absorbed by the sample andconverts it into an electric current.The microprocessor converts the value intothe desired measuring unit and displays it onthe LCD.The measurement process is done in twophases: setting the meter to zero and actualmeasurement.The cuvet is an optical element and hencehas an important role in the measurementprocess. Both the measurement and thecalibration cuvets must be optically identicalto provide the same measurement conditions.It is also important that the surface of thecuvet is clean and free from scratches ordents, in order to avoid measurementinterference due to unwanted reflection andabsorption of light.It is recommended that wherever possible thecuvet walls are not touched by the operator.Furthermore, in order to maintain the sameconditions during the zeroing and themeasuring phases, it is necessary to closethe cuvets to prevent any contamination.

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of the display to remind the user that every timea measurement is taken, the value is stored inthe next available lot number.

REVIEWING THE LOGGED BUFFER

To review the memorizedvalues, press together ALTand .

The meter will scroll all the data in the buffershowing the lot number, value, date and time.e.g. The first recorded reading in the buffer is

lot # 0, 0.35 mg/L of Free Chlorine, memo-rized on 23rd August at 3:34 pm;The second logged data relates to lot# 1, 1.35 mg/L of the customized param-eter, logged on 23rd August at 3:55 pm.

First lot Second lot

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CLEARING THE MEMORYAfter all the buffer (memory) is taken up, theLCD will blink “Full”.

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FUNCTIONAL DESCRIPTION

1) PrimaryLCD: The four-digit LCD shows all

segments for several secondswhen the meter is switchedon. It then displays fourdashes to indicate “ready tomeasure”. It is also the areawhere the date, time andvalue of last calibration areshown. In “Read” and “Zero”mode, “SIP” is shown toindicate “Sample In Progress”.The upper level also indicatesthe concentration or turbidityof the sample, as well as

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LOGGING WITH C 114

C 114 allows user to log 25 time/day-taggedmeasurements. User can easily turn the log-ging mode on and off, review the loggedmemory, review the current lot number andclean the buffer (memory). C 114 also re-minds user if its memory is full.

TURNING THE LOG MODE ON OR OFFEnter the diagnostic mode by pressing ALTand CAL together.Select mode 12 andpress the key.The display will show the current(vacant) lot together with “LOG” ifthe log mode is on. Otherwise it willshow “----” if the log mode is off.By pressing the key, the meter togglesbetween the Log on and off positions. If thelog on mode is selected, every time a mea-

surement is taken (READ pressed) the rel-evant values will be stored in the current(vacant) lot number.

To quit diagnostic mode, press the ALT andCAL keys together again.The LCD will thenshow “CAL” and “Stor”for a few seconds. Ifthe log on mode was selected “LOG” will appearon the bottom left hand side

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To quit diagnostic mode,press the ALT and CALkeys together again.

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different diagnostic modes,such as “-BA-” for low bat-tery.

2) SecondaryLCD: The three-digit LCD shows the

current mode of measurementthat is “F CL”, “t CL”, “tr”,and diagnostic or calibrationmodes, such as “d 11”,“2 Fn”, “5 c1”.

3) DATE: Indicates that the upper levelof LCD is showing the cur-rent date, the date of last cali-bration or the date of loggedmeasurement in memory.

4) TIME: Indicates that the upper levelof LCD is showing the cur-rent time, the time of last cali-bration or the time of loggedmeasurement in memory.

5) LOBAT: Blinking segment warns userof low battery voltage.

6) LOG: If intermittent, it indicates thatthe user is in the scroll modeviewing the logged measure-ments. If fixed, it indicatesthat the meter is in the logmode and every readingtaken will be stored inmemory.

7) ON/OFF key:Turns the meter on and off.

8) ZERO/ key: In ion specific (colorimet-ric) mode, it zeros thesample. In calibration and di-agnostic modes, it functionsas ENTER (not used in tur-bidity mode).

9) READ/ key: Takes the measurement of

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DIAGNOSTIC MODE

C 114 facilitates operations by providing adiagnostic mode. In this mode, user can setor verify different parameters necessary toensure optimum performance of the meter.To enter the diagnostic mode, turn the meteron and momentarily press ALT and CAL to-gether. The display will show four dashes to-gether with “d 00”:

Using the , and keys, select the re-quired diagnostic mode and press the key.The meter will execute one of the followinguser-diagnostic functions:

10 Customizes automatic shutdown11 Selects User or Factory functions12 Turns logging mode on or off21 Calibrates span in turbidimetric mode31 Calibrates span in colorimetric mode40 Clears the logged memory

The following diagnostic modes are reservedfor authorized service technicians:

00 Shows the Blank level in colorimetric mode01 Shows the Sample level in colorimetric mode02 Shows the Dark level in colorimetric mode05 Shows the Ground voltage06 Shows 5V on-board level07 Shows battery voltage level08 Shows 1.23V reference voltage level09 Shows -5V on-board level99 Shows software version number

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concentration/turbidity of thesample which is shown onthe LCD. In diagnostic or cali-bration mode, shifts the flash-ing digit to the right.

10) CAL key: If pressed during calibration,the calibration procedure willbe aborted and the last cali-bration data will be reinstated.If pressed together with theALT key for less then 3 sec-onds, the diagnostic mode willbe entered. If pressed to-gether with the ALT key again,the meter will quit diagnosticmode. If pressed for more then3 seconds, an intermittent“CAL” prompt will appear onthe upper LCD level and thecalibration procedure is en-tered.

11) GLP/Abs key: In ion specific mode, it willtoggle concentration/absor-bance readings on the upperLCD. In turbidity mode, date,time and the two calibrationvalues of the current modewill be shown. If pressed intime/date setup mode, themeter will quit current modewithout making any changesto current time/date.

12) key Scrolls upwards through theparameters to be measured.In calibration/diagnosticmode, increments the blink-ing digit by one. If pressedtogether with ALT while themeter is in logging mode, theupper LCD will show the data

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Subsequently, the up-per display will show“----”, indicating that themeter is calibrated andready to measure theconcentration of an unknown sample.By pressing the CAL key duringcalibration, user can leave the cali-bration mode at any time withoutchanging the previously stored calibration data.

C 114Range Turbidity 0.00 to 50.0 NTU*

Free Cl 0.00 to 2.50 mg/LTotal Cl 0.00 to 3.50 mg/L

ResolutionTurbidity 0.01 and 0.1 NTU*

Free Cl 0.01 mg/LTotal Cl 0.01 mg/L

AccuracyTurbidity ±0.02 NTU* or ±2% (whichever greater)

Free Cl ±0.03 mg/L; ±3%Total Cl ±0.03 mg/L; ±3%

Light Source Pure Green LED

Light Source Life Life of the instrument

Light Detector Two Silicon Photocells

Power Source 4 x 1.5V AA alkaline batteries

Battery Life 60 hours or 1000 measurements

Automatic SelectableShutdown 10, 20, 30, 40, 50 or 60 min.

Operating 0 to 50°C (32 to 122°F)Conditions 95% RH max (non-condensing)

Dimensions 220 x 82 x 66 mm(8.7 x 3.2 x 2.6")

Weight 510 g (18 oz.)

SPECIFICATIONS

* 1 NTU = 1 FTU

(date/time/value) in thememory.

13) ALT key: Alternative functions.

14) key: Scrolls downwards through theparameters to be measured.In calibration/diagnosticmode, decreases the blink-ing digit by one. If pressedtogether with ALT while themeter is in logging mode, theupper LCD will show the cur-rent lot number.

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After entering the cali-bration mode, the dis-play will show the firstpoint of the previouscalibration with themost significant digit blinking.

Using the , and keys, choose theconcentration of the first calibration standard.Insert the known standard into the cuvet holderand make sure that the notch is positionedsecurely into the groove. Press the key.The display will indicate sample in progress.

After the first calibra-tion point is memo-rized, the LCD will in-dicate the second pointof the previous calibration with the most sig-nificant digit blinking.

Using the , , keys, choose the knownconcentration of the second calibration stan-dard.Insert the standard into the cuvet holder andmake sure that the notch is positioned se-curely into the groove. Press the key. Thedisplay will blink “SIP” again.

After the second calibration point is memo-rized, the unit will store the calibration data,time and date in the EEPROM while intermit-tently indicating “CAL” and “Stor” for severalseconds.

OPERATIONAL GUIDE

SET CURRENT TIME/DATE

To set or change the current time, turn on themeter. After initialization routine, the LCD willshow:

Press and hold the ALT and GLP keys to-gether. Display will show the current date inMM.DD format (e.g. August 28 is shown as08.28).

Release the keys. The month digits will blink.Make the necessary adjustments with the and keys. To skip to the day digits, pressthe key.

After the adjustments, press the key. Theunit will store the newly set month-day datain its EEPROM and will show the currenttime by a 24 hour clock HH.MM format, e.g.2:28 pm is:

Similarly, make the necessary adjustmentsas described above and press . The newlyset up “month - day - hour - minute” data willbe stored in memory.

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Using the and keys,set the lower part ofthe LCD to “d 11” andthen press the key.The key is used as a toggle function inthis mode and allows the user to select be-tween USER (USR) or FACTORY (FCT) pro-grammed functions.

Select the USER mode and press ALT andCAL keys together to leave the diagnosticmode. The display of the meter will indicatefour dashes together with a number 0 or 1 onthe lower part of the LCD.

Press and hold the ALT and CAL keys to-gether for at least three seconds. The upperdisplay will start flashing “CAL” for approxi-mately three seconds.

To confirm entry into the calibrationmode, press the CAL key againwhile “CAL” is still blinking.If the CAL key is notpressed, the upper rowof the display will show“----”, indicating that thecalibration mode wasnot entered. In which case, hold down theALT and CAL keys together for 3 seconds torestart the procedure.

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CURRENT TIME/DATE RECALL

To recall current TIME/DATE press and holdthe ALT and READ keys together. The cur-rent time and an intermittent “TIME” will bedisplayed.

Release the keys.

Press and hold the ALT and READ keysagain and the meter will show the currentdate together with an intermittent “DATE”.

TURBIDITY MEASUREMENTS

Fill the vial with the sample. Thesurface of the vial should be cleanand scratch free.

Turn the meter on. After the initialization rou-tine, the LCD will show:

Use the and keys to set the lower level ofthe LCD to turbidity (tr).

Insert the sample into the cuvetholder and ensure that thenotch on the cap is positionedsecurely into the groove.

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Using , , keys setthe lower part to “d 31”.

Insert the previously prepared deionized wa-ter standard into the cuvet holder and makesure that the notch on the cap is positionedsecurely into the groove. Press the key.

The display will blink “-Lc-” for several seconds, in-dicating that adjustmentof the LED for thecolorimetric measurements is in progress.After this, a sequence of numbers between-511 to 512 will appear on the upper LCDindicating the different levels of LED lightintensity. In approximately one minute, theadjustment will be made and the calibrationdata will be stored in the non-volatile memory.Display will show fourdashes again indicatingthe end of the zero cali-bration procedure.Press the ALT and CALkeys again to leave thediagnostic mode.Two-point customizedcalibrationTo enter the colorimetric calibration mode, pressmomentarily both the ALT and CAL keys. TheLCD will show four dashes and “d00”.

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Press READ. The meter will intermittentlydisplay “SIP” on the upper level of the LCD.

After a few seconds the display will show theturbidity value, e.g. 5.34 NTU:

COLORIMETRIC MEASUREMENTSTurn the meter on. After the initialization rou-tine, the LCD will display:

Use the and keys tochoose the desired param-eter:F CL Free Chlorine t CL Total Chlorine

Measuring ChlorineFill the vial with the sample (blank). Thesurface of the vial should be clean and scratchfree.Insert the blank sample into the cu-vet holder and ensure that the notchon the cap is positioned securelyinto the groove. Press ZERO.

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After the second calibration point is memo-rized, the unit will store the calibration datatogether with time and date in the EEPROMwhile intermittently indicating “CAL” and “Stor”for several seconds.

Subsequently, the up-per display will show“----”, indicating that themeter is calibrated andready to measure turbidity of an unknownsample.By pressing CAL during calibration,user can quit the calibration modeat any time without changing thepreviously stored calibration data.

COLORIMETRIC CALIBRATIONZero calibrationTo calibrate the span of the meter, fill thecuvet with a clean deionized water sample.Inspect and thoroughly clean the surface ofthe vial.

Turn the meter on and press both ALT andCAL momentarily.

The display will showfour dashes and “d 00”.The second “0” will blinkto allow the user tomake a selection.

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For the Free or Total Chlorine add the con-tent of its respective packet:

Replace the cap and shake the cuvet. Forbest results wait 2½ mins. for Total Chlorine.Insert the reacted sample into the cuvet holderand ensure that the notch on the cap is posi-tioned securely into the groove. Press READ.

The meter will show “SIP” for a few secondsand then the concentration:

Measurements in user-customized modeNote: The meter must be calibrated for this

purpose. Follow the two-point custom-ized calibration on page 26 beforeproceeding.

Turn the meter on and by momentarily press-ing both ALT and CAL.

1 x1 x1 x1 x1 x

The meter will show “SIP” for a few secondsand then a zero indication:

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If the CAL key is notpressed, the upper dis-play will show “----”, in-dicating that calibrationmode was not entered. In which case, holddown the ALT and CAL keys together for 3seconds to restart the procedure.After entering the cali-bration mode, the dis-play will show the firstpoint of the previouscalibration. The most significant digit will alsobe blinking.Using the , , keys, set the turbidity offirst calibration standard (from 0.00 to 50.0 NTU).Insert the standard vial into the cuvet holderand ensure that the notch is positioned se-curely into the groove. Press the key. The

display will indicateSample In Progress(SIP).After the first calibra-tion point is memorized, the LCD will indicatethe second point of the previous calibrationwith the most significant digit blinking.

Using the , , keys, set the turbidity of thesecond calibration standard (from 0.00 to 50.0NTU). Insert the standard into the cuvet holderand make sure that the notch is positionedsecurely into the groove. Press the key.The display will indicate “SIP” again.

The LCD will show fourdashes on the upperand “d 00” on the lowerpart of the LCD with thesecond “0” flashing:Using the , and keys change the lowerrow of the display toshow “d 11”:Press the key. This key is also used as atoggle between USER (USR) and FACTORY(FCT) programmed functions. Select the USERmode (if necessary by pressing the keymore than once):

Press ALT and CAL until four dashes aredisplayed on the upper display and “# fn” areshown in the lower part of the LCD.

Using the and keys select the numberfrom 0 to 1 where the appropriate calibrationdata have been stored.Add the appropriate reagent into the blanksample cuvet. Shake and allow a few sec-onds for color to develop.

Insert the reacted sample into the cuvet holderand make sure that the notch on the cap is

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The display will blink“-Lt-” for several sec-onds, indicating thatthe LED is being ad-justed for the turbidimetric channel.Afterwards, a sequence of numbers between-511 to 512 will appear on the upper part ofthe LCD indicating different levels of LED lightintensity.In approximately one minute, the adjustmentwill be made and the calibration data storedin the non-volatile memory.The display will showfour dashes again indi-cating the end of thespan calibration proce-dure.Press the ALT and CAL keys togetheragain to leave thediagnostic mode.

Two-point customized calibrationTo enter the turbiditycalibration mode, themeter should be in“turbidity” mode.

Use the and keys to set the lower level ofthe LCD to “tr”.

To enter the calibration mode, press and holdthe ALT and CAL keys together for at leastthree seconds. The upper display will startflashing “CAL” for approximately three sec-onds.

To confirm entry into the calibra-tion mode, press the CAL keyagain while “CAL” is blinking.

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positioned securely into the groove. PressREAD.

The meter will first show “SIP” for a fewseconds and afterwards the sample concen-tration:

CALIBRATION

TURBIDITY CALIBRATIONThe meter should be properly calibrated witha standard prepared as described in USEPAmethod 180.1.

Span calibrationTo calibrate the span of the meter, fill thecuvet with the primary turbidity formazinestandard of 50 NTU.

Inspect and clean thoroughly the sur-face of the vial.

Shake the standard vigorously for a fewseconds and wait a few minutes for thebubbles to disappear.Turn the meter on and press both ALT andCAL momentarily.

The LCD will show fourdashes on the upper and“d 00” on the lower part ofthe LCD with the second“0” blinking.

Using the , and keyschange the lower row of thedisplay to show “d 21”.Insert the previously pre-pared 50 NTU standard into the cuvet holderand make sure that the notch on the cap ispositioned securely into the groove. Press

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