Apera Instruments PH850 User manual

Ve r s i o n 2.0
PH850 Portable pH Meter
User Manual

Ve r s i o n 2.0
Contents
1 Introduction .......................................................................................................................................... 1
1.1 Measurement Parameters ............................................................................................................... 1
1.2 Basic Features ................................................................................................................................ 1
1.3 pH Measurement Features ............................................................................................................. 1
2 Specifications ...................................................................................................................................... 2
2.1 Main Specifications ......................................................................................................................... 2
2.2 Other Specifications: ....................................................................................................................... 2
3 Instrument Description ........................................................................................................................ 2
3.1 LCD Display： ................................................................................................................................. 2
3.2 Keypad Functions ........................................................................................................................... 3
3.3 Meter Socket ................................................................................................................................... 4
3.4 Reading Stability Display Mode ...................................................................................................... 4
3.5 Automatic Lock Display Mode ......................................................................................................... 5
3.6 Automatic Power-off ........................................................................................................................ 5
3.7 Manual Temperature Compensation (MTC) .................................................................................... 5
4 pH Measurement ................................................................................................................................. 5
4.1 pH Electrode Information ................................................................................................................ 5
4.2 pH Calibration Consideration .......................................................................................................... 5
4.3 pH Meter Calibration (with an example of 3-point calibration) ........................................................ 7
4.4 Sample Test ..................................................................................................................................... 8
4.5 pH Electrode Maintenance .............................................................................................................. 9
5 mV Value Measurement: ................................................................................................................... 10
5.1 ORP Measurement ........................................................................................................................ 10
5.2 Notes ............................................................................................................................................. 10
6 Parameter Setting ............................................................................................................................. 11
7 What’s in the Kit ................................................................................................................................ 13
8 Recommended pH Electrodes for Different Applications .................................................................. 14
9 Warranty ............................................................................................................................................ 15
10 Appendix I: Parameter Setting & Factory Default Setting ................................................................. 16
11 Appendix II: Abbreviation Glossary ................................................................................................... 17

1
1 Introduction
Thank you for purchasing PH850 portable pH meter.
This product is a great combination of advanced electronics technology, sensor technology, and
software design, made for general water solution applications such as water treatment, environmental
monitoring, pools and spas, hydroponics, aquaculture, education, beverage making, cooling tower, etc.,
especially ideal for field use. In order to use and maintain the meter properly, please read the manual
carefully before use.
1.1 Measurement Parameters
Measurement
parameters
PH850
pH/mV
!"
Conductivity/TDS
"
Temperature
!"
1.2 Basic Features
● The microprocessor-based portable meter features automatic
calibration, automatic temperature compensation, function setup,
self-diagnostics, automatic power-off and low voltage display.
● The meter’s digital filter improves measurement speed and accuracy. There is a stable reading
indication on the display.
● The package includes a portable case, a meter, electrodes, standard solutions and all accessories,
which is convenient to use in field.
● The meter is dust proof and waterproof, meeting the IP57 rating.
1.3 pH Measurement Features
● 1-3 points automatic calibration, the meter provides calibration guide and automatic checking
function.
● The meter can recognize pH standard buffer solutions automatically. USA series and NIST series
buffer solutions can be selected.
● The meter provides three types of reading stability criteria.

2
2 Specifications
2.1 Main Specifications
Specifications
pH
Range
(0.00~14.00) pH
Resolution
0.1/0.01 pH
Accuracy
±0.01 pH ±1 digit
Temperature compensation
(0~100)˚C (manual or automatic)
mV
Range
±1,000 mV
Resolution
1 mV
Accuracy
±0.2% F.S ±1 digit
Temperature
Range
0~100˚C
Resolution
0.1˚C
Accuracy
±0.5˚C ±1 digit
2.2 Other Specifications:
Power
AAA batteries × 3 (1.5V×3)
IP rating
IP57
Dimension & Weight
Meter: (86×196×33) mm / 335 g
Portable case:(330×270×82)mm/1.3kg
PH850, EC850
3 Instrument Description
3.1 LCD Display
：
Diagram-2
LCD
HOLD
⑬

3
(1) — Parameter mode icons
(2) — Measurement reading
(3) — Prompts of special display mode
(4) — Units of measurement
(5) — Te m p e r a t u r e u n i t s ( ° C a n d ° F )
(6) — Units of pH and conductivity calibration value
(7) — pH and conductivity calibration value, and prompts of special display mode
(8) — Te m p e r a t u r e v a l u e , a n d p r o m p t s o f s p e c i al d i s p l ay m o d e
(9) — Te m p e r a t u r e c o m p e n s a t i o n i c o n s
ATC — automatic temperature compensation, MTC — manual temperature compensation
(10) — Calibration guide icon
(11) — Stability icon of readings
(12) — Low battery icon, when this icon appears, please replace the battery
(13) — Automatic reading hold icon
3.2 Keypad Functions
3.2.1. Keypad operations
Short press ----- <1.5 seconds; Long press ----- >1.5 seconds.
Turn on the meter: Press to turn on the meter.
Turn off the meter: In the measurement mode, press and hold for 2 seconds to turn off the meter.
Note: In the calibration mode or the parameter setup mode, pressing is invalid. Please press
key to return to the measurement mode, then press to turn off the meter.
Diagram-3
Keypad

4
Chart -1 Keypad operations and descriptions
Keypad
Operations
Descriptions
Short press"
# In the power-off mode, press this key to turn on the meter
Long press
# In the measurement mode, press and hold this key for 2 seconds to
turn off the meter.
Short/long press
Select measurement parameters:
# PH850 pH meter: →
# In the measurement mode: long press to enter manual temperature
compensation mode, then long press or momentary press this key
to change the temperature value (only one direction)."
# In the parameter setup mode, press this key to change the serial
number of the main menu and the submenu (only one direction)
# In the submenu mode, press this key to change parameters and
setup (only one direction)
Short press"
# In the measurement mode, press this key to enter the calibration
mode
# In the calibration mode or the parameter setup and auto lock-up
(HOLD) mode, press this key to return to the measurement mode
Short press
# In the measurement mode, press this key to enter the parameter
setup main menu"
# In the calibration mode, press this key to make calibration
# In the parameter setup mode, press this key to select programs"
3.3 Meter Socket
Chart-2 Sockets for Meters
3.4 Reading Stability Display Mode
When the measuring value is stable, smiley icon stays on LCD,
see Diagram – 4. If the smiley icon does not appear or flash, please do
not get the reading value or make calibration until the measuring value is
stable. Per parameter P1.3, there are 3 criteria for stability standard:
(Normal), (High), and (Low). The factory default is set “Normal”.
Models
Photos
Description
PH850 pH meter
"
●BNC socket (right) — connect
pH electrode or ORP electrode,
●RCA socket (middle) — connect
temperature probe
Diagram- 4

5
“High” is set for stability for longer time, “Low” is set for stability for shorter
time. User can select suitable stability criteria according to different testing
requirement.
3.5 Automatic Lock Display Mode
Select On from parameter P4.6 to turn on automatic lock-up display function.
When the reading value stabilizes more than 10 seconds, the meter locks the
measuring value automatically and displays HOLD icon, see Diagram – 5.
In the HOLD mode, press to release lock-up.
3.6 Automatic Power-off
The meter will be power-off if there is no operation for 20 minutes. The time of auto power-off can be set in
parameter setting P3.2
3.7 Manual Temperature Compensation (MTC)
When the temperature probe does not connect to the meter, long press key, temperature value flashes,
then long press key or short press key to change the temperature value in one way, and press
to confirm the temperature value to achieve Manual Temperature Compensation (MTC).
4 pH Measurement
4.1 pH Electrode Information
The meter connects to 201T-F plastic three-in-one combination pH electrode with built-in temperature
sensor, with automatic temperature compensation function. Electrode housing is made of polycarbonate
engineering plastics, which is corrosion and impact resistant. The BNC socket of electrode connects pH
socket. RCA socket connects temperature socket. When dipping pH electrode in the solution, please stir
the solution briefly to eliminate any air bubbles and allow it to stay in the solution until the reading is
stable
Note: The 201T-F Combination Glass pH/temp. Electrode is only suitable for general water solutions’ pH
measurement. For special applications such as low ion concentration or complex solutions, please refer to
Section 10 to find the most suitable pH electrode model.
4.2 pH Calibration Consideration
4.2.1. Standard buffer solution
The meter uses two series of standard buffer solution: USA series and NIST series, 3 solutions for each
series which are corresponding to calibration indication icons. Please see Chart - 3 for the two series of
standard buffer solution.
Diagram - 5

6
Chart - 3 pH standard buffer solution series
Calibration guide icons
pH standard buffer solution series
USA series (USA)
NIST series (NIS)
Three-point
calibration
1.68 pH and 4.00 pH
1.68 pH and 4.01 pH
7.00 pH
6.86pH
10.01 pH and 12.45 pH
9.18 pH and 12.45 pH
4.2.2. Three-point calibration
The instrument can perform 1-3 points calibration. The first point calibration must use 7.00 pH (or 6.86 pH)
standard solution, then select other standard solution to perform the second and the third point calibration.
See chart – 4.
Chart - 4 Three-point calibration mode
USA standard
NIST standard
Icons!
Suited range!
One-point
calibration
!"##$%&$
'"('$%&$
Accuracy
≤ ±0.1pH
Two-point
calibration
!"##$%&)*"##$+,$-"'(%&$
'"('$%&)*"#-$+,$-"'(%&$
Range<7.00pH
!"##$%&)-#"#-$+,$."*/%&$
'"('$%&)0"-($+,$-."*/%&$
Range>7.00pH
Three-point
calibration
!"##%&)*"##$+,-"'(%&$
)-#"#-$+,-."*/%&$
'"('%&)*"#-+,$-"'(%&$
)0"-($+,$-."*/%&$
Large Range
4.2.3. Calibration frequency
Calibration frequency depends on the sample, the electrode performance, and the required accuracy. For
high accuracy measurements (≤ ±0.03pH), the meter should be calibrated immediately before taking a
measurement. For general accuracy (≥±0.1pH), the meter can be calibrated and used for approximately
one week before the next calibration.
The meter must be recalibrated in the following situations:
(a) New probe or probe that has not been used for a long time
(b) After measuring acid (pH<2) or alkaline solutions (pH>12)
(c) After measuring a solution that contains fluoride or a concentrated organic solution
(d) If the solution’s temperature differs greatly from the calibration solution temperature.

7
4.3 pH Meter Calibration (with an example of 3-point calibration)
4.3.1. First point calibration
(a) Press key to enter the calibration mode, “CAL 1”
flashes at the top right of LCD and “7.00 pH” flashes at the bottom right of
LCD, indicating using pH 7.00 buffer solution to make the 1st point calibration.
(b) Rinse pH electrode in distilled or deionized water, allow it to dry, and
submerge it in pH7.00 buffer solution. Stir the solution briefly and allow it to
stay in the buffer solution until a stable reading is reached. When stable icon
stays on LCD, press key to calibrate, then 1st point calibration is
finished, the meter enters in measurement mode of one-point calibration.
Calibration guide icon will display at the bottom left of LCD.
4.3.2. Second point calibration
Press key to enter the calibration mode, “CAL 2” flashes at the top right
of LCD indicating to make the 2nd point calibration. Rinse pH electrode in
distilled or deionized water, allow it to dry, and submerge it in pH4.00 buffer
solution. Stir the solution briefly and allow it to stay in the buffer solution until
a stable reading is reached. The meter’s display will show scanning and
locking process of calibration buffer solution at the bottom right of LCD. When
the meter locks 4.00 pH, stable icon stays on LCD, press key to
calibrate the meter. LCD will display electrode slope of acidity range, then 2nd
point calibration is finished, the meter enters measurement mode of two-point calibration. Calibration guide
icons will display at the bottom left of LCD.
4.3.3. Third point calibration
Press key to enter the calibration mode, “CAL 3” flashes at the top right of LCD indicating to make the
3rd point calibration. Rinse pH electrode in distilled or deionized water, allow it to dry, and submerge it in
pH10.01 buffer solution. Stir the solution briefly and allow it to stay in the buffer solution until a stable
reading is reached. The meter’s display will show scanning and locking process of calibration buffer solution
at the bottom right of LCD. When the meter locks 10.01pH, stable icon stays on LCD, press the
key to calibrate the meter. LCD will display electrode slope of alkalinity range, then 3rd point calibration is
finished, the meter enters in measurement mode of three-point calibration.
Calibration guide icons will display at the bottom left of LCD.
Notes:
(a) The meter can perform 1-3 points calibration. When the 1st point calibration is done, the meter will enter
measurement mode of one-point calibration. Two-point and three-point calibration are in the same manner.
(b) During the calibration process, if measuring value is not stable yet (when does not stay on and the
key is pressed, then Er 2 will display. (See chart – 5). To s o l v e t h e problem, s i m p l y wait for to
Diagram- 6

8
stay on the screen before pressing
(c) To exit calibration mode and go back to measurement mode, press key.
4.4 Sample Test
4.4.1. Rinse pH electrode in distilled or deionized water, allow it to dry, and submerge it in tested solution.
Stir the solution briefly and allow it to stay in the tested solution until icon stays on LCD and a stable
reading is reached, which is the pH value of test solution.
!
!
!
!
!
!
Diagram – 7 Calibration and measurement process of pH meter
4.4.2. Self-diagnosis information
During the process of calibration and measurement, the meter has self-diagnosis functions, indicating the
relative information as below, please refer to chart – 5.
Chart – 5 Self-diagnosis information of pH measurement mode
Display
Icons
Meaning
Check and Fix
Wrong pH buffer solution or the
recognition of calibration solution out of
range
1. Check whether pH buffer solution is correct.
2. Check whether the meter connects the
electrode well.
3. Check whether the electrode is damaged.
Pressing key too soon
Press key after icon appears and stays
During calibration, the measuring value
is not stable for ≥3min.
1. Check whether there are bubbles in glass bulb.
2. Replace with new pH electrode.
pH electrode performance error
zero potential <-60mV or >60mV,
slope <75%
1. Check whether there are bubbles in glass bulb.
2. Check whether pH buffer solution is correct.
3. Replace with new pH electrode.
Press to turn on
the meter
!
Press key to
enter the calibration
mode.
Submerge the electrode
in pH7.00 solution, press
key when
icon
appears.
1-point calibration is
done, the meter
enters measurement
mode
2-point calibration is
done, the meter
enters measurement
mode
!
Submerge the electrode
in pH4.00 solution, press
key when
icon appears.
Submerge the electrode
in pH10.01solution,press
key when
icon appears.
3-point calibration is
done, the meter
enters measurement
mode
"
Sample
Test
1
st point calibration
3rd point calibration
Press key to
enter the calibration
mode.
Press key to
enter the calibration
mode.
2nd point
calibration

9
4.4.3. pH temperature principle
Please note that the closer the temperature of the sample solution to the calibration solution, the more
accurate the readings.
4.4.4. Factory default setting
For factory default setting, please refer to parameter setting P1.4 (Item 7.3). All calibration data is deleted
and the meter restores to the theory value (zero electric potential of pH is 7.00, the slope is 100%). Some
functions restore to the original value (refer to appendix -1). When calibration or measurement fails, please
restore the meter to factory default setting and then perform re-calibration or measurement. Please note
once set the factory default, all the data deleted will be irretrievable.
4.5 pH Electrode Maintenance
4.5.1. Daily maintenance
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 or deionized 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 solution. The soaking/storage
solution is 3M KCL (SKU: AI1107). Using other brand’s storage solution might cause potential damage to
the electrode.
The electrode should not be stored in distilled or deionized water, protein solution or acid fluoride solution.
In addition, do not soak the electrode in organic silicon lipids. For best accuracy, always keep the meter
clean and dry, especially the meter’s electrode socket. Clean with medical cotton and alcohol if necessary.
4.5.2. Calibration buffer solution
For calibration accuracy, the pH of the standard buffer solution must be reliable. The buffer solution should
be refreshed often, especially after heavy use.
4.5.3. Protect glass bulb
The sensitive glass bulb at the front of the combination electrode should not come in contact with hard
surfaces. Scratches or cracks on the electrode will cause inaccurate readings. Before and after each
measurement, the electrode should be washed with distilled or deionized water and dried. Do not clean the
glass bulb with a tissue for it will affect the stability of the electrode potential and increase the response
time. The electrode should be thoroughly cleaned if a sample sticks to the electrode. Use a solvent if the
solution does not appear clean after washing.
4.5.4. Renew glass bulb
Electrodes that have been used over a long period of time will become aged. Submerge the electrode in
0.1mol/L hydrofluoric acid for 24 hours, then wash the electrode in distilled or deionized water, then
submerge it in soaking solution for 24 hours. The method to prepare 0.1mol/L hydrofluoric acid dilute 9mL
hydrochloric acid in distilled or deionized water to 1000mL. For serious passivation, submerge the bulb in

10
4% HF (hydrofluoric acid) for 3-5 seconds, and wash it in distilled or deionized water, then submerge it in
the soaking solution for 24 hours to renew it.
4.5.5. Clean contaminated glass bulb and junction (please refer to Chart-6)
Chart – 6 Clean contaminated glass bulb and junction
Contamination
Cleaning Solutions
General tough contaminants
Apera Electrode Cleaning Solution (SKU: AI1166)
Organic lipid
Dilute detergent (weak alkaline)
Resin macromolecule
Dilute alcohol, acetone, ether
Proteinic sediment
Apera Electrode Cleaning Solution (SKU: AI1166)
Paints
Dilute bleacher, peroxide
Note: The electrode housing is polycarbonate. When use cleaning solutions, take cautions on
carbon tetrachloride, trichlorethylene, tetrahydrofuran, acetone, etc., which will dissolve the
housing and invalidate the electrode.
5 mV Value Measurement:
5.1 ORP Measurement
Press key, and switch the meter to mV measurement mode. Connect 301Pt-C ORP electrode (SKU:
AI1303, sold separately) and dip it in sample solution, stir the solution briefly and allow it to stay in the
solution until icon stays and then record the reading, which is ORP value. ORP is in short for Oxidation
Reduction Potential. The unit is mV.
5.2 Notes
5.2.1. ORP measurement does not require calibration. When the user is not sure about ORP electrode
quality or measuring value, use ORP standard solution to test mV value and see whether ORP electrode
or meter works properly.
5.2.2. Clean and Activate ORP Electrode
After the electrode has been used over long period of time, the platinum surface will get polluted, which
causes inaccurate measurement and slow response. Please refer to the following methods to clean and
activate ORP electrode:
(a) For inorganic pollutant, submerge the electrode in 0.1mol/L dilute hydrochloric acid for 30 minutes, then
wash it in distilled or deionized water, then submerge it in the soaking solution for 6 hours.
(b) For organic or lipid pollutant, clean the platinum surface with detergent, then wash it in distilled or
deionized water, then submerge it in the soaking solution for 6 hours.
(c) For heavily polluted platinum surface on which there is oxidation film, polish the platinum surface with

11
toothpaste, then wash it in distilled or deionized water, then submerge it in the soaking solution for 6 hours.
6 Parameter Setting
6.1 Main Menu
In the measurement mode, press key to enter P1.0, then press to switch to main menu:
P1.0→P3.0. Please refer to diagram – 9.
P1.0: pH parameter setting; P3.0: Basic parameter setting.
6.2 Submenu
7.2.1. In P1.0 mode, press key to enter submenu P1.1 of pH parameter setting, then press key
to switch among submenu: P1.1→P1.2→P1.3→P1.4, see Diagram – 9.
7.2.3. In P3.0 mode, press key to enter submenu P3.1 of basic parameter setting, then press
to switch among submenu: P3.1→P3.2→P3.3, see Diagram – 9.
P1.1 Select pH standard solution
P1.2 Select resolution
P1.3 Set stability criteria
P1.4 Restore to factory setting
P3.1 Select temperature unit
P3.2 Automatic power-off setup
P3.2 Automatic lock-up setup
Submenu of pH parameter setting
Submenu of basic parameter setting
Main menu of parameter setting
Diagram 9

12
6.3 Submenu of pH Parameter Setting (press key to switch)
P1.1. – Select pH standard solution (USA-NIST)
1. In measurement mode, press key to enter P1.0 mode, then press
to enter P1.1.
2. Press key, USA flashes, press key to select USA→nIS, press
to confirm. USA-USA series; nIS-NIST series.
3. After confirming parameter, press key to enter P1.2 mode, or press
key to return to the measurement mode.
P1.2. – Select resolution (0.01 – 0.1)
1. Press key, 0.01 flashes, press key to select 0.01→0.1, press
key to confirm.
2. After confirming parameter, press key to enter P1.3 mode, or
press key to return to the measurement mode.
P1.3. – Set reading stability criteria (Normal – High – Low)
1. Press key, nor flashes. Press key to select nor→HI→Lo, press
to confirm.
Nor – Normal, Hi – High, Lo – Low.
2. After confirming parameter, press key to enter P1.4 mode, or
press key to return to the measurement mode.
P1.4. –Restore factory setting (No – Yes)
1. Press key, no flashes. Press key to select no→YES, press
to confirm, the meter returns to the measurement mode.
No – Do not restore, Yes – Restore to factory setting.
2. If not choosing Yes , press key to return to the measurement mode.
6.4 Submenu of Basic Parameter Setting (press key to switch)
P3.1. Select temperature unit (°C—°F).
1. In P3.0 mode, press key to enter P3.1 mode, please refer to
the left Diagram.
2. Press key, °C flashes, then press key to select °C→°F, press
key to confirm.
3. When parameter is confirmed, press key to enter mode P3.2
or press key to return to the measurement mode.

13
P3.2 – Automatic power-off setup (10→20→30→On)
1. Press key, On flashes, press key to select 10→20→30→On
press key to confirm.
On – turn off automatic power-off; Time unit is minutes.
2. After confirming the parameter, press key to enter mode P3.3 or
press key to return to the measurement mode.
P3.2 – Automatic lock-up setup (Off→On)
1. Press key, OFF flashes, press key to select OFF→On, press
to confirm.
Off – not set; On–set (the reading is automatically locked when
stabilizes"10 seconds.)
2. When Parameter is confirmed, press key to return to the
measurement mode.
7 What’s in the Kit
No.
Include
Quantity
PH850
1.
PH850 portable pH meter
1 set
#
2.
201T-F plastic three-in-on pH electrode
1 pc
#
3.
pH standard buffer
solution (4.00 pH /7.00pH/10.01/50mL)
1 bottle each
#
4.
Portable case
1 pc
#
5.
Manual
1 book
#

14
8 Recommended pH Electrodes for Different Applications
Application
Ideal Apera pH Electrodes to Use with 85
0
Series Meter
General water solutions
201T-F, LabSen 211, LabSen 213
Beverage, beer, wine…
LabSen 211, LabSen 213
Cosmetics
LabSen 851-S
Corrosive solutions
LabSen 861
Culture medium
LabSen 823, LabSen 821, LabSen 851-S
Dairy products (milk, cream, yogurt, mayo, etc.)
LabSen 823, LabSen 821
High-Temperature solution
LabSen 861
Low-temperature solution
LabSen 881
Meat
LabSen 763
Micro-volume solution
LabSen 241-6, LabSen 241-3
Purified Water (Low ion concentration samples)
LabSen 803, LabSen 801
Soil
LabSen 553
Solid or semi-solid samples (cheese, rice, fruit, etc.)
LabSen 753, LabSen 751, LabSen 251
Strong acid samples
LabSen 831
Strong alkaline samples
LabSen 841
Surface test (skin, paper, carpet, etc.)
LabSen 371
TRIS buffer solutions
LabSen 211, LabSen 213, LabSen 221
Viscous liquid
LabSen851-S, LabSen 851-H
Wastewater, emulsion, complex and caustic solutions
LabSen 333, LabSen 331

15
9 Warranty
We warrant this instrument to be free from defects in material and workmanship and agree to repair or
replace free of charge, at the option of APERA INSTRUMENTS, LLC, any malfunctioned or damaged
product attributable to the responsibility of APERA INSTRUMENTS, LLC for a period of THREE YEARS
for the instrument and SIX MONTHS for the probe from the delivery.
This limited warranty does NOT cover any issues due to:
•Accidental damage
•Improper use
•Normal wear and tear
•Transportation
•Storage
•Failure to follow the product instructions
•Unauthorized maintenance, modifications, combination or use with any products, materials,
processes, systems or other matter
•Unauthorized repair

16
10 Appendix I: Parameter Setting & Factory Default Setting
Modes"
Prompts"
Parameter setting items"
Abbreviation"
Description"
Restore to
factory
default
P1.0
pH
P1.1
Select pH buffer solution
USA$NIST
USA
P1.2
Select resolution"
"
0.01$0.1
0.01
P1.3
Set reading stability
criteria
"
Normal%High%Low
Normal
P1.4
Restore to factory default
setting
No$Yes
No
P2.0
Cond.
P2.1
Select electrode constant"
"
1.0$10.0$0.1
1.0
P2.2
Select reference
temperature
15~30$
./1$
P2.3
Adjust temperature
compensation coefficient
0.00~9.99
2.00
P2.4
Adjust TDS factor
0.40~1.00
0.71
P2.5
Restore to factory default
setting"
"
No$Yes
No
P3.0
Basic
Parameters
P3.1
Select temperature unit
&"
123$
1$
P3.2
Automatic Power-off
setup
""""""""
10$20$30$On
20
P3.3
Automatic Lock-up setup
&"
/
Off

17
11 Appendix II: Abbreviation Glossary
Modes
Prompts
Code and
abbreviation
In English
Description
P1.0
pH
P1.1
Standard buffers
Standard buffer solution
P1.2
"
Resolution
Resolution"
P1.3
Stability criteria
Set up reading stability
criteria
P1.4
Factory default setting
Factory default setting
P2.0
Conductivity
P2.1
"
Cell
Constant Cell
P2.2
Reference temperature
Reference temperature"
P2.3
Temperature
compensation coefficient
Temperature
compensation coefficient
P2.4
Total dissol v e d s o l i d
TDS
P2.5
!
Factory default setting
Factory default setting
P3.0
Basic parameters
P3.1
&"
&
&
"
P3.2
!
Auto close
Automatic Power-off
P3.3
&
&
&

18