Apera Instruments WS200 User manual

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WS200 Fluoride/pH/Conductivity
7-in-1 Portable Meter Kit
Instruction Manual
APERA INSTRUMENTS, LLC
www.aperainst.com

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Table of Contents
1Overview.........................................................................................................................- 3 -
1.1 Basic Functions .................................................................................................................... - 3 -
1.2 Features of Fluoride Measurement....................................................................................... - 3 -
1.3 Features of pH Measurement ............................................................................................... - 3 -
1.4 Features of Conductivity Measurement ................................................................................ - 3 -
2Technical Parameters：...................................................................................................- 4 -
2.1 Fluoride............................................................................................................................... - 4 -
2.2 pH ....................................................................................................................................... - 4 -
2.3 mV ...................................................................................................................................... - 4 -
2.4 Conductivity: ....................................................................................................................... - 5 -
2.5 Other technical parameters:................................................................................................. - 5 -
3Instrument Description....................................................................................................- 5 -
3.1 LCD Display.......................................................................................................................... - 5 -
3.2 Operation keys..................................................................................................................... - 6 -
3.3 Data Storage, Recall Data, and Clear Data ............................................................................. - 7 -
4Fluoride Ion Concentration Measurement........................................................................- 7 -
4.1 Preparation.......................................................................................................................... - 7 -
4.2 Calibration........................................................................................................................... - 8 -
4.3 Sample Measurement.......................................................................................................... - 8 -
4.4 Parameter Settings............................................................................................................... - 9 -
4.5 Notes................................................................................................................................... - 9 -
5pH Measurement...........................................................................................................- 10 -
5.1 Preparing the Meter........................................................................................................... - 10 -
5.2 Meter Calibration............................................................................................................... - 10 -
5.3 Sample Test........................................................................................................................ - 12 -
5.4 Parameter Settings............................................................................................................. - 12 -
5.5 Notes................................................................................................................................. - 15 -
5.6 The Self-diagnose Information.......................................................................................... - 16 -
6ORP Measurement.........................................................................................................- 17 -
6.1 Sample Test........................................................................................................................ - 17 -
7Conductivity Measurement:...........................................................................................- 17 -
7.1 Preparation Work............................................................................................................... - 17 -
7.2 Meter’s Calibration ............................................................................................................ - 17 -
7.3 Sample Test:...................................................................................................................... - 18 -
7.4 Notes................................................................................................................................. - 18 -
7.5 Parameter Setting: ............................................................................................................. - 20 -
7.6 Notes................................................................................................................................. - 22 -
8Complete Kit..................................................................................................................- 23 -
9Warranty .......................................................................................................................- 23 -
10 Appendix 1. Fluoride Concentration Conversion Table.................................................- 24 -

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1 Overview
Thank you for purchasing the Apera Instruments WS200 pH/Condivity/Fluoride 7-in-1 Portable
Meter (Hereon after referred as the meter). Before using the product, please read this manual carefully to help
you properly use and maintain the instrument For technical support, please contact us at [email protected]m
or [phone].
The WS200 meter is widely used for drinking water, surface water and other water treatment applications,
ideal for both in-field and laboratory testing.
1.1 Basic Functions
◼Automatic calibration and temperature compensation (ATC), data storage, self-diagnostics,
automatic shutdown, low-battery reminder
◼Adopting digital filtering and intelligence to improve the instrument's responsiveness and accuracy
of measurement data.
◼Meets IP57 Waterproof and dustproof rating, ideal for use under harsh environment.
1.2 Features of Fluoride Measurement
◼Patented structure of the 3-in-1 ion electrode contains fluoride ion-selective electrode, reference
electrode, and temperature electrode. This design generates quick stability, fast response, and is easy to
use.
◼No need for stirring or added reagents, directly measuring the ion concentration of fluoride in a quick
and simple manner, directly measure the fluoride concentration with three different units: mg/L,
ppm and pF.
1.3 Features of pH Measurement
◼1-3 points of automatic calibration, with calibration icons and self diagnosis function.
◼Automatic recognition of up to 12 different pH standard buffer solutions, there are three series of
standard buffer solutions to choose from: U.S.A, NIST, and China.
1.4 Features of Conductivity Measurement
◼1-3 points of automatic calibration, with calibration icons and self diagnosis function.

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◼Automatically recognize up to 8 kinds of conductivity standard solutions. User can choose from
two series of standard solutions: Europe & USA and CHINA.
◼Automatically adjusts conductivity measuring range, the meter will do perform automatic
temperature compensation test for purified water and high purified water less than 10μS/cm, which
greatly improves the measuring accuracy. It is especially suitable for use in electrical power,
microelectronics, and medicine industries.
2 Technical Parameters：
2.1 Fluoride
Measuring range
0.02 ppm to 1900 ppm
Display units
mg/L, ppm, pF
Accuracy
±0.02 ppm or ±5% of reading (which ever is greater)
Temperature
Compensation Range
(0-80 ) ℃ ( Automatic)
2.2 pH
Measuring range
(-2.00 - 19.99 )pH
Resolution
0.1/0.01 pH
Accuracy
± 0.01 pH ± 1 digit
Temperature Compensation Range
(0 - 100 )℃(Automatic)
2.3 mV
Measuring range
-1999mV ~ 0 ~ 1999mV
Resolution
1mV
Accuracy
±0.1% FS

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2.4 Conductivity:
Measuring Range
Conductivity：（ 0.00~19.99）μS/cm （20.0~199.9）μS/cm
（200~1999）μS/cm （2.00~19.99）mS/cm
（20.0~199.9）mS/cm
TDS: （0 ~ 100）g/L Salinity：（0 ~ 100）ppt
Resistivity：（ 0 ~ 100）MΩ·cm
Resolution
0.01/0.1/1μS/cm 0.01/0.1 mS/cm
Accuracy
±1.0% F.S
ATC Range
（0 - 50）℃（Auto）
Electrode Constant
0.1 / 1 / 10 cm-1
Base Temperature
25℃、20℃ and 18℃
2.5 Other technical parameters:
Data Storage
800 Sets
Storage Content
Numberings, measurements, units of measurement and a
temperature values
Power Supply
AA Battery (1.5VX2)
Size and Weight
Instrument:(65X120X31) mm/180g ; Suitcases:(360X270X76)
mm/1.5Kg
Quality and Safety
Certification
ISO 9001:2015, CE, RoHS
IPClass
IP57 Dustproof and waterproof
3 Instrument Description
3.1 LCD Display

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①—— Parameter mode
②—— Measuring value
③—— Measured value storage and display of numbers, symbols indicate:
M+—Store Measured value
RM - Recall measurement values Icon ;
④—— Measurement unit
⑤—— Temperature measurement and unit
⑥—— Smiley face; icon indicates stable readings
⑦—— Instrument calibration indicator
⑧—— Low battery reminder
3.2 Operation keys
The meter has 5 operation keys in total.
3.2.1 — Switch on / off key
3.2.2 — Calibration key
（a）When in the measurement mode, press this key to enter calibration mode.
（b）When in the parameter setting mode, press this key to change the number or the ON/OFF
state.
3.2.3 — Function key
(a) When in pH measurement mode, short press to change measurment parameters, long press
this key to enter parameter setting mode P1, P2, P3 ……
(b) When in Conductivity measurement mode, press this key to enter parameter settings mode
P1, P2, P3 ……
(c) When in Fluoride measurement mode, press this key to enter parameter setting mode P1, P2,
P3 ……
3.2.4 — Backlight and enter key
(a) When in the measurement mode, short press (< 1.5s ) to turn the backlight display on or off;
(a) When in the calibration mode or the parameter setting mode, press this key to confirm, and to
make the meter enter measuring state;
(c) When in pH measurement mode, press this key to change resolution simultaneously:
0.01→0.1 pH
(d) When in Conductivity measurement mode, press this key to change parameter simultaneously:
TDS→SAL→RES→COND.
(e) When in Ion measurement mode, press this key to change parameter mode simultaneously:
mg/L → ppm → pX
3.2.5 — The combination key of memory storage and recall memory.
（a）When in the measurement mode, short press this button (< 1.5s) to save the measuring data.
Long press this button(＞2s) to display the stored measuring data.
(b) When in the parameter setting mode, press this button to change the unit % → mol → g/cm3

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→ g/L or turn the meter ON/OFF.
3.3 Data Storage, Recall Data, and Clear Data
3.3.1 Data Storage
While in the measurement mode, when the measurement data is stable and the smiley face icon appears, short
press key (＜1.5s), LCD will display “ M+” icon and a storage serial, and meanwhile storing all of
the measurement information. It can store up to 300 groups.
3.3.2 Display measurement information
(a) While in the measurement mode, long press (＞2s), meter will display the last stored information,
and the storage number and “RM” icon will appear in the lower right corner of the LCD, and the complete
measurement information. Again short press or meter will in turn display all the saved data.
Hold or to quickly check the data.
(b) In the data displaying mode (there are RM and storage number in the upper right corner of the LCD),
press key to return to measurement mode.
Clear the stored data: In the data displaying mode, press key for 5 seconds, LCD will appear CLr for
2 seconds. It means that all the storage has been eliminated, and returns to measurement mode.
4 Fluoride Ion Concentration Measurement
4.1 Preparation
4.1.1 Press key to power on, connect F501-S fluoride ion electrode (pay attention to inserting
direction), the meter automatically switches to fluoride ion concentration measurement mode.
4.1.2 Hold to change fluoride ion concentration unit from mg/l, ppm to pX , release the button after
selection.
4.1.3 If it is a new electrode or if it is your first time use, activate the electrode by soaking it in 19.00
mg/L calibration solution for 1 hour. For regular usage, soak 10 to 20 minutes to activate it. When the
reading is fully stabilized ( stays on screen), the electrode activation is finished. Then you can
start calibration and measurement. (Please note that the reading during activation is random).

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4.2 Calibration
4.2.1 Press , LCD displays 0.19 mg/L, and LCD top right corner CAL and the bottom left L will be
blinking, indicating that the meter has entered the 1st point calibration mode and the calibration
solution is 0.19 mg/l; Rinse the fluoride-ion electrode in distilled or deionized water and shake off the
excess water; dip the electrode into 0.19 mg/L calibration solution, stir gently and let it stand still.
4.2.2 When the reading is stable and icon stays on screen , press key again to finish 1st point
calibration. End and 19.0 mg/L will be displayed after a few seconds. CAL and H will be flickering
on the screen, indicating the meter has entered the 2nd point calibration mode and the calibration
solution is 19.00 mg/L.
4.2.3 Take out the electrode and shake off excess solution, then dip it into 19.00 mg/L calibration solution,
stir gently and let it stand still. When the reading is stable and stays on screen, press key
again to finish 2nd point calibration. After a few seconds End shows up, indicating the end of
calibration; LCD’left corner shows two-point calibration icons L and H; The instrument automatically
enters measurement mode.
4.3 Sample Measurement
4.3.1 Rinse the fluoride-ion electrode in distilled or deionized water and shake off excess water or blot dry
with filter paper. Soak the electrode into your sample solution, stir gently and let it stand still; get the
measurement when the reading is stable and stays on screen.
4.3.2 Hold to show Fluoride concentrations in different units, release after selection.
4.3.3 Short press key, the meter enters the mV mode and displays the mV value of the fluoride
ion concentration.
4.3.4 After test, rinse off the electrode with distilled water, shake off excess water, and store dry with the
cap on.

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4.4 Parameter Settings
Table (4-3)
Symbol
Parameter sets the project
Code
Parameters
P1
Temperature unit selection
˚C / ˚F
P2
Backlight display time setting
0-1-3-6 min
P3
Auto power off time setting
0-10-20 min
P4
Restore to factory default
settings
OFF-ON
4.4.1 Temperature units ° C/ºF selection (P1)
Long Press to enter P1，remaining operations see section 5.4.5
4.4.2 Backlight display time setting (P2)
In P1, long press to enter P2，remaining operations see section 5.4.6
4.4.3 Auto-off time setting (P3)
In P2, press to enter P3，remaining operations see section 5.4.7
4.4.4 Restore factory default (P4)
In P3, press to enter P4，remaining operations see section 5.4.8
4.5 Notes
4.5.1 The meter does not automatically recognize calibration solutions. Please make sure to use correct
calibration solution according to the displayed reminders "0.19 mg/L" or "19.00 mg/L".
4.5.2 The calibration solution can be easily polluted, especially for low concentration solution (0.19 mg/l).
Please pay attention to avoid contamination otherwise a large measurement error will occur. Replace
the solution after 4~5 times of use.
4.5.3 When storing the electrode, just rinse it out and shake off excess water, then store dry with the electrode
cap on.
4.5.4 When testing solutions in the order from low-concentration to high-concentration, the electrode does
not need to be rinsed. Just shake off excess water or blot dry with filter paper. If it’s from high-

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concentration to low-concentration, you need to rinse the electrode with distilled or deionized water,
otherwise it will affect the accuracy significantly.
4.5.5 Typically the meter needs to be calibrated before use every time. But when requirement of accuracy
is low, calibration is not necessary. Or try the electrode in the calibration solution, if the error is very
small, calibration is not necessary.
4.5.6 According to the theory of Isothermal measurements of ion-selective electrode, the smaller the
difference of temperature between test solution and the calibration solution, the higher the
measurement accuracy is. Typically, temperature difference between test solution and calibration
solution should ≤±15℃; for high accuracy measurement, the temperatures should be the same.
4.5.7 When the meter is functioning abnormally, please set P4 as “ON”to reset the meter to factory default
mode, and then perform calibration and measurements again.
5 pH Measurement
5.1 Preparing the Meter
Connect the 201T-S pH Electrode to the meter (pay attention to the inserting direction); loosen the cap of the
storage bottle of electrode; screw off the storage bottle; Press to turn on meter. The meter automatically
switches to pH measurement mode.
5.2 Meter Calibration
5.2.2. Use distilled water to rinse off electrode and then dry it with clean tissue, then soak it into the pH7.00
buffer solution, stir the electrode gently and let it stand still,
5.2.1. Press to enter calibration mode, LCD displays C1, indicating the first point of calibration; Wait
for a stable reading and to appear and stay, then press again, the LCD will show a
blinking 7.00 pH, indicating the 1st point of calibration is completed; a stable pH value and a
blinking C2 will be displayed, indicating the first point calibration has been finished and the
meterenters the second point of calibration.
5.2.3. Rinse the pH electrode in distilled water and dry it, then soak it into the pH4.00 buffer solution, stir
the electrode gently and let it stand still, waiting for a stable reading and a smiley face icon to appear

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and stay, then again press , the LCD will show a blinking 4.00 pH, a stable pH value and a
blinking C3 will be displayed, indicating the second-point calibration has been finished and the
meter enters the third-point calibration.
5.2.4. Rinse the pH electrode in distilled water and dry it, then soak it into
the pH 10.01 buffer solution, stir the electrode gently and let it stand
still,, waiting for a stable reading and a smiley face icon to appear
and stay, then again press , the LCD will show a blinking
10.01 pH. A stable reading and L M H calibration icons will be displayed, see picture (4-1),
indicating the three-point calibration has been finished and the meter automatically returns to
measurement mode.
5.2.5. Notes
(a) This meter can perform one-point, two-point or three-point automatic calibrations. After the first
point calibration (see item 5.2.2.), press to confirm one-point calibration and return to
measurement mode. The indication icon M standing for one-point calibration will appear on the
lower left corner of LCD. When the requirement of accuracy is ≤±0.1pH, users can perform a one-
point calibration with the pH7.00 buffer solution.
(b) After the second-point calibration, (see item 5.2.3.), press to confirm two-point calibration
and return to measurement mode. The indication icon L and M for twp-point calibration will appear
on the lower left corner of LCD. User can choose pH4.00 and pH7.00 to calibrate if the measurement
is within the acidity range and choose pH7.00 and pH10.01 to calibrate if within the alkalinity range.
(c) Users should perform a three-point calibration to reach a more accurate measurement if the
measuring range is wide, or if the electrode has been used for long or has aging phenomenon. If it’s
a new electrode, a three-point calibration is necessary to adjust the meter’s slope to match the pH
electrode.

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5.3 Sample Test
Soak the pH electrode into the sample solution after rinsing and drying, hold the electrode still. Take
the readings when the smiley face icon shows up and stays on screen (indicates a stable reading).
pH isothermal measurement principle
According to the theory of Isothermal measurements, the smaller the difference of the temperatures
between test solution and the calibration solution, the higher the measument accuracy is. Typically,
temperature difference between test solution and calibration solution should ≤±15℃; for high
accuracy measurement, the temperatures should be the same.
5.4 Parameter Settings
5.4.1. pH measuring parameter setting (Chart (5-1))
Chart (5-1)
Prompt
Mark
Parameter Setting Items
Code
Parameters
P1
pH buffer solution series selection
SOL
USA(U.S.A series)
NIS (NIST series)
CH (China series)
P2
Purified water pH temperature
compensation setting
PU1
OFF-On
P3
Ammonia added purified water pH
temperature compensation setting
PU2
OFF-On
P4
Temperature unit setting
℃ ℉
P5
Back light display time setting
BL
0-1-3-6min
P6
Auto power off setting
AC
0-10-20min
P7
Restore to Factory Default
OFF-On
5.4.2. pH buffer solution series selection (P1)
(a) Press key, meter enters P1 mode: see picture (4-2).
(b) Press or key to choose buffer solution series:
( Europe & U.S.A series) —1.68, 4.00, 7.00,10.01 and 12.45 pH

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(NIST series) — 1.68, 4.01, 6.86, 9.18 and 12.45 pH
( (China series) — 1.68, 4.00, 6.86, 9.18 and 12.46 pH
(c) Press key to enter next parameter setting or press key to confirm and return to
measurement mode.
5.4.3. Purified water pH temperature compensation setting (P2)
(a) Short press key in the mode P1, the meter enters mode P2,
see picture (4-3).
(b) Press or to choose ON or OFF.
(c) Press key to enter next parameter setting or press key to confirm and return to
measurement mode.
(d) The default setting is “ OFF ”.
Note: A PU-1 icon will appear in the upper right corner of the LCD if purified water temperature
compensation function is set by the user.
5.4.4. Ammonia added purified water pH temperature compensation
setting (P3)
(a) Short press key in mode P2 to enter mode P3, see picture (4-
4).
(b) Press or key to choose ON or OFF
(c) Press key to enter next parameter setting or press key to confirm and return to
measurement mode.
(d) The default setting is “ OFF ”.
Note: A PU-2 icon will appear in the upper right corner of the LCD if purified water temperature
compensation function is set by the user.

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5.4.5. Temperature unit ℃/℉ setting (P4)
(a) Short press key in mode P3 to enter mode P4, see picture (4-
5).
(b) Press or key to choose temperature unit: ℃ or ℉.
(c) Press key to enter next parameter setting or press key to confirm and return to
measurement mode.
5.4.6. Backlight display time setting (P5)
(a) Short press key in mode P4 to enter mode P5, see picture (4-
6).
(b) Press or key to choose the time of back light auto
power off: 0 min, 1 min, 3 min or 6 min. The back light display
function will be closed if choosing a 0min.
(c) Press key to enter next parameter setting or press key to confirm and return to
measurement mode.
(d) The default setting for P5 is 1min.
5.4.7. Auto power off time setting (P6)
(a) Short press key in mode P5 to enter mode P6, see picture (4-
7).
(b) Press or key to choose the time: 0min, 10min or
20min. The auto power off function will be closed if choosing
0min.
(c) Press key to enter next parameter setting or press key to confirm and return to
measurement mode.
(d) The default setting for P6 is 10min.

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5.4.8. Restore to producer setting (P7)
(a) Short press key in mode P6 to enter mode P7, see picture (4-8).
(b) Press or key to choose “ON”, means that all the pH
measuring parameters have been restored to the factory default setting.
5.5 Notes
5.5.1. The frequency that you need to calibrate your meter depends on the tested samples, performace of
electrodes, and the requirement of the accuracy. For high-accuracy meaustements (≤ ±0.02pH), the meter
should be calibrated before test every time; For ordinary-accuracy measurements (≥±0.1pH), once calibrated,
the meter can be used for about a week or longer. In the following cases, the meter must be re-calibrated before
testing:
a) The electrode hasn’t been used for a long time or a new electrode is connected.
b) After measuring strong acid (pH<2) or strong base (pH>12) solutions.
c) After measuring fluoride-containing solution and strong organic solution
d) There is a significant difference between the temperature of the test sample and the temperature of the
buffer solution that is used in the last calibration.
5.5.2. The soaking solution contained in the supplied protective bottle is used to maintain activation in the
glass bulb and junction. Loosen the capsule, remove the electrode and rinse in distilled water before taking a
measurement. Insert the electrode and tighten the capsule after measurements to prevent the solution from
leaking. If the soaking solution is turbid or moldy, replace the KCL solution (Product# AI1107).
5.5.3. For calibration accuracy, the pH of the standard buffer solution must be reliable. The buffer solution
should be refreshed often, especially after heavy use. We recommend 10-15 times of use before replacing the
pH buffers.
5.5.4. Always keep the meter clean and dry; especially around the socket connecting the meter and electrode,
otherwise it may lead to inaccurate measurements or a damaged probe/meter. To clean, dry them with medical
cotton and rubbing alcohol if the connectors appear dirty.
5.5.5. The sensitive glass bulb at the front of the combination electrode should not contact with hard surfaces.
Scratches or cracks on the electrode will cause inaccurate readings. Before and after each measurement, the
electrode should be rinsed with distilled water and dried. If a sample sticks to the electrode or it’s contaminated,
the electrode should be thoroughly cleaned using a soft brush with soap water and then rinsed with
distilledwater. After that, soak it in the KCL solution again for 6 hours.

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5.5.6. How to clean and renew your pH electrode
For general contaminants, soak the electrode in Apera’s cleaning solution (AI1166) or detergent water for 30
minutes. Then use a soft brush to remove the contaminants. Afterwards, soak the probe in Apera 3M KCL
soaking solution (AI1107) for at least 1 hour. Rinse it off, then re-calibrate the tester before using.
For other special contaminants, refer to Table-8
Table-8 Clean contaminated glass bulb and junction
Contamination
Cleaning Solutions
Inorganic metal oxide
Dilute acid less than 1mol/L
Organic lipid
Dilute detergent (weak alkaline)
Resin macromolecule
Dilute alcohol, acetone, ether
Proteinic haematocyte sediment
Acidic enzymatic solution (saccharated yeast tablets)
Paints
Dilute bleacher, peroxide
a) Every pH electrode gradually loses its sensitvty and will eventually fail. The lifespan period for the 201T-
S pH Electrode is about 1-2 years depending on how it’s used and maintained.
b) When an abnormal reading appears during calibration or measurement, please set P7 to “ON” to restore
the meter to Factory Default settings, then re-calibrate the meter before measurement.
c) Electrodes that have been used for a long period of time will become aged. Submerge the electrode in
0.1mol/L hydrochloric acid for 24 hours, then rinse the electrode in distilled water, then submerge it in
3M KCL soaking solution for 24 hours. The method to prepare 0.1mol/L hydrochloric acid: dilute 9mL
hydrochloric acid in distilled or deionized water to 1000mL.
5.6 The Self-diagnose Information
When using the meter, the following icons might appear. This is the meter’s self-diagnose information, which
helps users identify problems occurring with the meter or the electrode.

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5.6.1 A still display of -2.00 pH or 19.99 pH —this icon appears when the value has surpassed the measuring
range. There will also appear such signs when the electrode is not well connected with the meter or
when the electrode is not immerged into the solution. This is a normal phenomenon.
5.6.2 Err1 —Abnormal electrode zero potential (<-60mV or >60mV)
5.6.3 Err2 —Abnormal electrode slope (< 85% or >105%)
When “Err1” or “Err2” appears, the meter can not work properly, please take the following steps to check
and fix the problem:
a) Check if the electrode bulb has air bubble, if has, please shake the electrode with force for a few times to
eliminate the air bubble inside the sensor.
b) Check the quality of buffer solution, if it is expired or contaminated. If so, please replace with new ones.
c) Set the meter to factory default mode then recalibrate it.
d) If the meter still can not recover to the normal state after doing the above steps, please replace a new pH
electrode.
6 ORP Measurement
6.1 Sample Test
6.1.1. Press key to turn on, and short press to switch to mV mode;
6.1.2. Connect the ORP probe (301Pt-S, sold separately), soak it into sample solution, stir gently and let it
stand still. Get the readings when the smiley face ion appears and stay on the screen.
7 Conductivity Measurement:
7.1 Preparation Work
7.1.1. Press key to turn on the meter;
7.1.2. Connect the 2301-S conductivity electrode into the meter.
7.2 Meter’s Calibration
Press key, “ CAL” will be flashing on the LCD, indicates the meter enters the calibration mode; rinse
the conductivity electrode with distilled or deionized water and dry it with clean tissue, then insert it into the
1413μS/cm calibration solution, hold still after stirring, when appears and stays, press again, LCD
will display flashing “1413μS/cm ” and End icon after a few seconds. And the meter will return to

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measurement mode automatically.
Calibration Note:
1) The meter’s conductivity mode has been calibrated before leaving factory, so generally users can use it
directly.
2) The conductivity can only can be calibrated under the mode of COND. Resistivity (RES), TDS, Sailinity
(SAL) are coverted from conductivity so they don’t need calibration as long as conductivity is calibrated.
7.3 Sample Test:
7.3.1 Connect the 2301T-S probe to the meter, soak it into sample solution, stir gently and let it stand still.
Get the readings when the smiley face ion appears and stay on the screen.
7.3.2 Press key to display the value of TDS, salinity or resistivity, which are converted from
conductivity.
7.4 Notes
7.4.1. This meter build-in below two kinds of calibration solution series, please set up in the parameters P1;
(a) ((U.S.A. series) —84μS/cm, 1413μS/cm, 12.88 mS/cm and 111.9 mS/cm
(b) (China series) —146.6μS/cm, 1408μS/cm, 12.85mS/cm and 111.3 mS/cm
7.4.2. This meter has a unique one-point calibration function, to choose one calibration solution whose
conductivity is close to the test samples. In general the most common calibration solution is 1413 μS/cm. Use
the equipped 2301-S conductivity electrode (K = 1 cm-1), and do calibration with 1413 μS/cm calibration
solution, the range can reach up to 100 mS/cm.
Chart (7-1)
Measuring range
0.05 to 20μS/cm
0.5μS/cm to 200mS/cm
Electrode constant
K=0.1cm-1(flow test)
K=1.0cm-1
Calibration solution
84μS/cm
84μS/cm
1413μS/cm
12.88 mS/cm
111.9 mS/cm
Calibration indication
icon

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7.4.3. The temperature compensation coefficient of the meter setting is 2.00%/℃ by default. However, the
conductivity temperature coefficient is different for different solutions. Users can refer chart (7-2), as well as
the data which they receive from experiments to set in the parameters setting of P4. At the same time, meter
will do automatic non-linear temperature compensation in the high purified water which less than 10 μ S / cm.
Note: When the coefficient of temperature compensation is set to be 0.00, that is, there is no
temperature compensation when testing, the measuring value is based on current temperature.
Chart (7-2)
Solution
Temperature compensation coefficient
NaCl salt solution
2.12%/℃
5%NaOH solution
1.72%/℃
Dilute ammonia solution
1.88%/℃
10% hydrochroric acid solution
1.32%/℃
5% sulfuric acid solution
0.96%/℃
7.4.5. The other parameters setting, please see the chart (7-3)
7.4.6. Attention: when the content of parameter setting is consistent with
content of factory default setting, conductivity measuring interface will display
as picture (6-1); when the content of parameter setting is different with content
of factory default setting, conductivity measuring interface will display as
picture (6-2); the code icon will appear on the upper right of LCD, when
parameters with code icon to be set more than two, LCD just displays one of
the codes; user should enter the parameter setting and carefully check the
contents of setting or restore the meter to factory default setting and set up the
parameters again.
Picture (6-1)
Picture (6-2)

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7.5 Parameter Setting:
7.5.1. Conductivity parameter setting (chart (7-3))
Chart (7-3)
Prompt Mark
Parameter Setting Items
Code
Parameter
P1
Standard solution series selection
7.6
USA (84μS/cm, 1413μS/cm, 12.88 mS/cm,
111.9 mS/cm)
CH (146.6μS/cm, 1408μS/cm,
12.85mS/cm, 111.3mS/cm)
P2
Electrode constant selection
0.1, 1, 10
P3
Benchmark temperature selection
25℃ 20℃ 18℃
P4
Temperature compensation
coefficient setting
0.00 to 9.99%
P5
Electrode constant setting
CC
P6
Temperature unit setting
℃ ℉
P7
Back light display time setting
BL
0-1-3-6min
P8
Auto power off time setting
AC
0-10-20min
P9
Restore to producer setting
OFF-On
7.5.2. Conductivity calibration solution series selection (P1)
(a) Press key, meter enters P1 mode, see picture (4-3);
(b) Press or key to choose the standard solution series
(c) Press key to enter the next parameter setting or press key return
to measurement mode.
7.5.3. Electrode constant selection (P2)
(a) Under P1 mode to short press key and enters P2 mode, see picture (4-4);
(b) Press or key to change the constant setting: 0.1→1.0→10.0.
(c) Press key to enter the next parameter setting or press key to return
to measurement mode.
(d) The producer setting of P2 is K=1.
Picture (6-3)
Picture (6-4)