Apera Instruments WS100 User manual

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WS100 Fluoride/pH Portable Meter Kit
Instruction Manual
APERA INSTRUMENTS (Europe) GmbH
www.aperainst.de

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Inhalt:
1Overview..............................................................................................................................- 3 -
1.1 Basic Functions.............................................................................................................- 3 -
1.2 Features of Fluoride Measurement................................................................................- 3 -
1.3 Features of pH measurement ........................................................................................- 3 -
2Technical Parameters：.......................................................................................................- 3 -
2.1 Fluoride .........................................................................................................................- 3 -
2.2 pH .................................................................................................................................- 4 -
2.3 mV.................................................................................................................................- 4 -
2.4 Other technical parameters: ..........................................................................................- 4 -
3Instrument Description .........................................................................................................- 4 -
3.1 LCD Display：...............................................................................................................- 4 -
3.2 Operation keys ..............................................................................................................- 5 -
3.3 Data Storage, Recall Data, and Clear Data: ..................................................................- 5 -
4Fluoride concentration measurement ...................................................................................- 6 -
4.1 Preparation....................................................................................................................- 6 -
4.2 Calibration .....................................................................................................................- 6 -
4.3 Sample Measurement ...................................................................................................- 6 -
4.4 Parameter Settings........................................................................................................- 7 -
4.5 Notes.............................................................................................................................- 7 -
5pH Measurement..................................................................................................................- 8 -
5.1 Preparing the Meter.......................................................................................................- 8 -
5.2 Meter Calibration ...........................................................................................................- 8 -
5.3 Sample Measurement ...................................................................................................- 9 -
5.4 Parameter Settings........................................................................................................- 9 -
5.5 Notes........................................................................................................................... - 11 -
5.6 Self-diagnose Information............................................................................................- 13 -
6ORP Measurement.............................................................................................................- 13 -
6.1 Sample Test.................................................................................................................- 13 -
7Complete Kit ......................................................................................................................- 13 -
8Warranty ............................................................................................................................- 14 -
9Appendix 1. Fluoride Concentration Conversion Table .......................................................- 14 -

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1 Overview
Thank you for purchasing the Apera Instruments WS100 Fluoride/pH Portable Meter Kit (Hereon
after referred as the meter). This fluoride/pH combo meter is widely used for drinking water, surface
water and other water treatment applications, ideal for both in-field and laboratory testing.
Before using the product, please read this manual carefully before use to help you properly use and
maintain the instrument.
For technical support, please contact us at [e-mail] or [phone]
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, measured value display when stable " " Icon.
•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: 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 CH.
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)

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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) °C (Automatic)
2.3 mV
Measuring range
-1999mV ~ 0 ~ 1999mV
Resolution
1mV
Accuracy
±0.1% FS
2.4 Other technical parameters:
Data Storage
300 Groups
Storage Content
Numberings, measurements, units of measurement and a
temperature value
Power Supply
AA Battery (1.5VX2)
Size and Weight
Instrument: (65X120X31) mm/180g
Case: (360X270X76) mm/1.5Kg
Quality and Safety
Certification
ISO9001:2015, CE
IP Class
IP57 Dustproof and waterproof
3 Instrument Description
3.1 LCD Display：
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

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3.2 Operation keys
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 ON/OFF state.
3.2.3 Function key
(a) In pH measurement mode, short press to change measurement parameters, long press
this key to enter parameter setting mode P1, P2, P3 ……
(c) In Fluoride measurement mode, press this key to enter parameter setting mode P1, P2,
P3 ……
3.2.4 Backlight and enter key
(a) In measurement mode, short press (< 1.5s) to turn the backlight display on or off;
(b) In calibration mode or the parameter setting mode, press this key to confirm, and enter
measurement
(c) In pH measurement mode, press this key to change resolution simultaneously:
(d) 0.01→0.1 pH
(e) In ion measurement mode, press this key to change parameter unit: mg/L → ppm → pX
3.2.5 The combination key of memory storage and recall memory.
(a) 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) In the parameter setting mode, press this button to change the unit % → mol → g/cm3 → 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 measuring 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 measuring information. It can store up to 300 groups.
3.3.2 Display measuring 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 measuring information. Again short press or meter
will in turn display all the measuring data, Hold or to quickly check the
measuring 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 the measuring mode.

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(c) Clear the stored measuring information: In the data displaying mode, press the key
for 5 seconds, LCD will appear CLr for 2 seconds. It means that all the storage has been
eliminated and returns to measuring mode.
4 Fluoride concentration measurement
4.1 Preparation
4.1.1 Press key to start connect F501-S fluoride ion electrode; (pay attention to inserting
direction), the meter automatically switches to the fluoride concentration measurement mode.
4.1.2 Hold to change fluoride 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).
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 flashing, indicating that the meter has entered the 1th 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, then 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 stabile and stays on screen,
then 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
bolt 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.

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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.
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 /°F 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 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 measuring 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-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 calibrated before use. 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

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the difference of temperature between test solution and the calibration solution, the higher the
measuring accuracy is. Typically, temperature difference between test solution and calibration
solution should ≤±15°C; 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 restore 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
5.2.1 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,
5.2.2 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 meter enters 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 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 measuring 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 measuring 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.

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(b) After the second-point calibration, (see item 5.2.3.), press to confirm two-point calibration
and return to measuring mode. The indication icon L and M for two-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.
5.3 Sample Measurement
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 measuring accuracy is. Typically,
temperature difference between test solution and calibration solution should ≤±15°C; for high
accuracy measurement, the temperatures should be the same.
5.4 Parameter Settings
5.4.1 pH measuring parameter setting (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:
U.S.A series —1.68, 4.00, 7.00,10.01 and 12.45 pH
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

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(c) Press key to enter next parameter setting or press key to confirm and return
to measuring 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 measuring 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 to enter next parameter setting or press
key to confirm and return to measuring 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.
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: °C or °F
(c) Press key to enter next parameter setting or press
key to confirm and return to measuring 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 measuring mode.
(d) The producer setting for P5 is 1min.