Apera Instruments PC 850 User manual

PC850 Version1.0
PC850
Portable pH/Conductivity Meter
Manual
PH 850 Portable pH Meter
EC 850 Portable Cond. Meter
PC 850 Portable pH/Cond. Meter
APERA INSTRUMENTS (Europe) GmbH
www.aperainst.de

PC850 Version1.0
Table of Contents
1. Introduction ---------------------------------------------------------------------------------------------------------------------------
2. Specifications -------------------------------------------------------------------------------------------------------------------------
3. Instrument Description -------------------------------------------------------------------------------------------------------------
3.1. LCD display----------------------------------------------------------------------------------------------------------------------
3.2. Keypad functions ---------------------------------------------------------------------------------------------------------------
3.3. Meter socket ---------------------------------------------------------------------------------------------------------------------
3.4. Reading stability display mode ----------------------------------------------------------------------------------------------
3.5. Automatic lock-up display mode ------------------------------------------------------------------------------------------
3.6. Automatic power off ---------------------------------------------------------------------------------------------------------
3.7. Temperature adjustment ----------------------------------------------------------------------------------------------------
4. pH measurement ---------------------------------------------------------------------------------------------------------------------
4.1. pH electrode information-------------------------------------------------------------------------------------------------------
4.2. pH calibration consideration -------------------------------------------------------------------------------------------------
4.3. pH calibration --------------------------------------------------------------------------------------------------------------------
4.4. Sample test ----------------------------------------------------------------------------------------------------------------------
4.5. pH electrode maintenance----------------------------------------------------------------------------------------------------
5. mV value measurement--------------------------------------------------------------------------------------------------------------
6. Conductivity measurement ----------------------------------------------------------------------------------------------------------
6.1. Conductivity electrode information-------------------------------------------------------------------------------------------
6.2. Conductivity calibration ------------------------------------------------------------------------------------------------------
6.3. Conductivity calibration--------------------------------------------------------------------------------------------------------
6.4. Relationship between TDS and Conductivity ------------------------------------------------------------------------------
6.5. Sample test------------------------------------------------------------------------------------------------------------------------
6.6. Conductivity electrode maintenance-----------------------------------------------------------------------------------------
7. Parameter setting----------------------------------------------------------------------------------------------------------------------
7.1. Main menu-------------------------------------------------------------------------------------------------------------------------
7.2. Submenu --------------------------------------------------------------------------------------------------------------------------
7.3. Submenu of pH parameter setting -------------------------------------------------------------------------------------------
7.4. Submenu of Conductivity parameter setting ------------------------------------------------------------------------------
7.5. Submenu of standard basic parameter setting -----------------------------------------------------------------------
8. Meter Kits-------------------------------------------------------------------------------------------------------------------------------
9. Warranty---------------------------------------------------------------------------------------------------------------------------------
Appendix I: Parameter setting & Factory default setting------------------------------------------------------------------------
Appendix II: Abbreviation Glossary-------------------------------------------------------------------------------------------------
Appendix III: Self-diagnosis information------------------------------------------------------------------------------------------ 22
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PC850 Version 1.0
1. Introduction
Thanks for purchasing PC850 portable pH/Conductivity meter.
This meter is a perfect combination of the most advanced electronics technology, sensor
technology, and software design, and is the most cost-effective portable electrochemical meter
designed for industrial and mining enterprises, power plants, water treatment engineering,
environmental protection industry, etc., especially ideal for general field use.
In order to use and maintain the instrument properly, please read the manual thoroughly before use.
(To improve instrument performance constantly, we reserve the right to change the manual and
accessories without giving notice in advance.)
1.1. Measurement Parameters
Measurement
parameters
PH850
EC850
PC850
pH/mV
√
√
Conductivity
√
√
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.
PC850 meter is able to measure up to 3 parameters simultaneously
and switch displays effortlessly. Please see Diagram -1:
two electrodes at most can be fit into the clip to measure 3 parameters
simultaneously.
●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 (for Model PH850 and PC850)
●1-3 points automatic calibration, the meter provides calibration guide and automatic checking
function.
●The meter is able to 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.
Diagram-1

PC850 Version 1.0
1.4. Conductivity Measurement Features (for Model EC850 and PC850)
●1-4 points automatic calibration, the meter provides calibration guide and automatic checking
function.
●The meter is able to switch between conductivity and TDS.
●The meter is able to recognize conductivity standard solutions automatically.
2. Specifications
2.1. Main specifications
Specifications
Models
pH
Range
(0.00~14.00) pH
PH 850
PC 850
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
Conductivity
Range
Conductivity: 0~200 mS/cm
(divided into five ranges):
(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
EC 850
PC 850
Resolution
0.01/0.1/1μS/cm 0.01/0.1 mS/cm
Accuracy
±1.0% F.S ±1digit
Temperature
compensation
(0 ~50)˚C (manual or automatic)
Electrode constant
0.1 / 1 / 10 cm-1
Temperature
Range
0~100˚C
PH 850
EC 850
PC 850
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
Portable case:(370×270×77)mm/1.8kg
PC850

PC850 Version 1.0
3. Instrument Description
3.1. LCD Display：
(1) —Parameter mode icons
(2) —Measurement reading
(3) —Prompts of special display mode
(4) —Units of measurement
(5) —Temperature units (°C and °F)
(6) —Units of pH and conductivity calibration value
(7) —pH and conductivity calibration value, and prompts of special display mode
(8) —Temperature value, and prompts of special display mode
(9) —Temperature compensation icons
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
Diagram-2
LCD
Diagram-3
Keypad
HOLD
⑬

PC850 Version 1.0
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.
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:
●pH 850 pH meter: →
●EC 850 Conductivity meter: →
●PC 850 pH/Conductivity 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 in 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 in 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

PC850 Version 1.0
3.3. Meter socket Chart-2 Sockets for Meters
3.4. Reading Stability Display Mode
When the measuring value is stable, smiley icon appears 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”.
“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-Up 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. Temperature Adjustment
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 key to make confirmation.
Models
Photos
Description
pH 850 pH meter
●BNC socket (right) —connect
pH electrode or ORP electrode,
●RCA socket (middle) —connect
temperature probe
EC 850 Conductivity
meter
●Eight-pin socket (left) —connect
conductivity electrode
PC 850 pH/Conductivity
meter
●BNC socket (right) —connect pH
electrode or ORP electrode,
●RCA socket (middle) —connect
temperature probe
●Eight-pin socket (left) —connect
conductivity electrode
Diagram- 4
Diagram - 5

PC850 Version 1.0
4. pH Measurement
4.1. pH Electrode Information
The meter matches 201T-F plastic three-in-one combination pH electrode with built-in temperature
sensor to realize automatic temperature compensation. Electrode housing adopts polycarbonate
engineering plastics which is corrosion and impact resistant. The BNC socket of electrode connects
pH socket; RCA socket connects temperature socket. When dip the electrode in the solution, please
stir the solution briefly and allow it to stay in the solution until a stable reading is reached.
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.
Chart - 3 pH standard buffer solution series
Icons
pH standard buffer solution series
USA series
NIST series
Three-point
calibration
4.00 pH
4.01 pH
7.00 pH
6.86 pH
10.01 pH
9.18 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
7.00 pH
6.86 pH
Accuracy
≥±0.1pH
Two-point
calibration
7.00 pH →4.00 pH
6.86 pH →4.01 pH
Range< 7.00pH
7.00 pH →10.01 pH
6.86 pH →9.18 pH
Range> 7.00pH
Three-point
calibration
7.00→4.00→10.01 pH
6.86→4.01→9.18 pH
Large Range
4.2.3. Calibration intervals
Calibration intervals depend on the sample, the electrode performance, and the required accuracy.
For high accuracy measurements (≤ ±0.03pH), the meter should be calibrated immediately before

PC850 Version 1.0
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
4.3. pH Meter Calibration (with an example of three-point calibration)
4.3.1. First point calibration
(a) Press key to enter into the calibration mode, “ CAL 1 ”
blinks at the top right of LCD and “7.00 pH” blinks at the bottom right of
LCD, indicating using pH 7.00 buffer solution to make the 1st point calibration.
(b) Rinse pH electrode in pure 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
displays 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 displays at the bottom left of LCD. See Diagram-6.
4.3.2. Second point calibration
Press key to enter into the calibration mode, “ CAL 2 ”
blinks at the top right of LCD indicating to make the 2nd point calibration.
Rinse pH electrode in pure 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 displays
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 in measurement mode
of two-point calibration. Calibration guide icons display at the bottom left of LCD.
4.3.3. Third point calibration
Press key to enter into the calibration mode, “ CAL 3 ”blinks at the top right of LCD indicating
to make the 3rd point calibration. Rinse pH electrode in pure 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 displays on
LCD, press key to calibrate the meter. LCD will display electrode slope of alkalinity range, then
Diagram- 6

PC850 Version 1.0
3rd point calibration is finished, the meter enters in measurement mode of three-point calibration.
Calibration guide icons 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 in 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 appear
and the key is pressed, then Er 2 displays. See chart –5.
(c) To exit from the calibration mode, press key.
4.4. Sample Test
4.4.1. Rinse pH electrode in pure 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 appears on LCD and a stable
reading is reached, which is the pH value of tested solution. Diagram –7 is the calibration and
measurement process of pH meter
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.
Press to turn
on the meter
Press key to
enter into the
calibration mode.
Submerge the electrode
in pH7.00 solution, press
key when icon
appears.
One-point calibration
is done, the meter
enter in measurement
mode
Two point calibration
is done, the meter
enter in 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.
Three point
calibration is done,
the meter enter in
measurement mode
Sample
Test
1st point calibration
3rd point calibration
Press key to
enter into the
calibration mode.
Press key to
enter into the
calibration mode.
2nd point
calibration

PC850 Version 1.0
Chart –5 Self-diagnosis information of pH measurement mode
Display
Icons
Contents
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.
Press key when measuring valueis
not stable during calibration.
Press key after icon appears
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.
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 pure 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. (Preparation:
26g KCL dissolved in 100ml pure water).
The electrode should not be soaked in pure water, protein solution or acid fluoride solution for long
periods of time. In addition, do not soak the electrode in organic silicon lipids.
For best accuracy, always keep the meter clean and dry, especially the and electrode connectors.
Clean with medical cottons and alcohol if necessary.
4.5.2. Calibration buffer solution

PC850 Version 1.0
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 pure 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 hydrochloric acid for 24 hours, then wash the electrode in pure water, then
submerge it in soaking solution for 24 hours.
The method to prepare 0.1mol/L hydrochloric acid: dilute 9mL hydrochloric acid in pure water to
1000mL. For serious passivation, submerge the bulb in 4% HF (hydrofluoric acid) for 3-5 seconds,
and wash it in pure 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
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
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.

PC850 Version 1.0
5. mV Value Measurement
5.1. Press key, and switch the meter to mV measurement mode. Connect ORP electrode (need
to purchase separately) and dip it in sample solution, stir the solution briefly and allow it to stay in
the solution until icon appears and get the reading, which is the ORP value.
ORP stands 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 pure 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 pure
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 toothpaste, then wash it in pure water, then submerge it in the soaking solution for 6 hours.

PC850 Version 1.0
6. Conductivity Measurement
6.1. Conductivity Electrode Information
6.1.1. Conductivity electrode
Model 2301T-S plastic conductivity electrode with constant K=1.0 and built-in temperature sensor,
can realize automatic temperature compensation. The electrode housing is POM plastic which is
corrosion resistant and impact resistant. When submerge the conductivity electrode in solution, stir
the solution briefly to eliminate the air bubbles and improve response and stability.
6.1.2. Conductivity electrode constant
The meter matches conductivity electrodes of three constants: K=0.1, K=1.0 and K=10.0. Please
refer to chart-7 for measuring range. Set constant in parameter setting P2.1 and refer to clause 7.4
Chart –7 Electrode constant and measuring range
Range
＜20 μS/cm
0.5 μS/cm~100 mS/cm
＞100mS/cm
Conductivity
electrode constant
K=0.1 cm-1
K=1.0 cm-1
K=10 cm-1
Standard solution
84μS/cm
84 μS/cm
1413 μS/cm
12.88 mS/cm
111.9 mS/cm
6.2. Conductivity Calibration
6.2.1. Conductivity calibration solutions
The meter uses conductivity standard solution of 84 μS/cm, 1413 μS/cm, 12.88 mS/cm and 111.9
mS/cm. The meter can recognize the standard solution automatically, can perform one-point or
multi-point calibration (the maximum is four-point calibration). The calibration indication icons
correspond to the four standard values ( icon corresponds to two standards). See chart –8:
Chart –8 Conductivity standard solution series
Calibration guide icons
Calibration solution series
Range
84 μS/cm
0-200 μS/cm
1413 μS/cm
200-2,000 μS/cm
12.88 mS/cm
2-20 mS/cm
111.9 mS/cm
20-200 mS/cm
6.2.2. Calibration intervals
(a) The meter is calibrated before leaving the factory and can generally be used right out of the box.
(b) Normally perform calibration per month.
(c) For high accuracy measurements or large temperature deviation from the reference temperature
(25°C), perform calibration per week.

PC850 Version 1.0
(d) Use conductivity standard solution to check whether there is error. Perform calibration for large
error.
(e) For new electrode or factory default setting, perform 3-point or 4-point calibration. Choose closer
standard solution to the sample solution to perform 1- point or 2-point calibration.
6.2.3. Reference temperature
Reference temperature of factory default is 25°C. Other reference temperature can also be set for
range 15°C –30°C. Select per parameter setting P2.2 and see clause 7.4.
6.2.4. Temperature coefficient
The temperature compensation coefficient of the meter setting is 2.0%/°C. However, the
conductivity temperature coefficient is different from solutions and concentration. Please refer to
chart –9 and the data collected during testing. Set per parameter setting P2.3. and see clause 7.4.
Note: When the coefficient for the temperature compensation is set to 0.00 (no
compensation), the measurment value will be based on the current temperature.
Chart -9 Temperature compensation coefficient of special solutions
Solution
Temperature compensation coefficient
NaCl solution
2.12%/°C
5% NaOH solution
1.72%/°C
Dilute ammonia solution
1.88%/°C
10% hydrochloric acid solution
1.32%/°C
5% sulfuric acid solution
0.96%/°C
6.2.5. Avoid contamination of standard solution
Conductivity standard solution has no buffer. Please avoid being contaminated during usage.
Before submerging the electrode in standard solution, please wash the electrode and allow it dry.
Please do not use the same cup of conductivity standard solution repeatedly, especially for standard
solution of low concentration (84μS/cm). The contaminated standard solution will affect accuracy.
6.3. Conductivity Calibration (take 1413μS/cm as an example)
6.3.1. Rinse the electrode in pure water, allow it to dry, wash with a little of standard solution and
submerge it in standard solution. Stir the solution briefly and allow it to stay in the solution until a
stable reading is reached.
6.3.2. Press key to enter into the calibration mode.

PC850 Version 1.0
The meter’s display will show blinking “CAL”at the top right, and scanning and locking process of
calibration solution at the bottom right. When the meter locks 1413 mS,
stable icon will display on LCD. Press key to complete calibration.
The meter will return to measuring mode and is displayed on bottom
left of the LCD screen. See diagram-8.
6.3.3. For multi-point calibration, please repeat clause 6.3.1-6.3.2 until all
the calibration is done. The meter can repeat calibration in the same
calibration solution until the stable value is reached.
6.3.4. Notes:
(a) If press key before stable icon appeared on LCD screen,
Error indication icon Er 2 will be shown. See Chart -11.
(b) Press key to exit calibration mode.
6.4. Relations between TDS and Conductivity
6.4.1. TDS and conductivity is linear related. The conversion factor
is 0.40-1.00.Adjust the factor from parameter P2.4. The factory default
setting is 0.71 and please refer to Item 7.4. The meter only needs to be
calibrated in Conductivity mode, then after calibration of conductivity,
the meter can switch from conductivity to TDS or salinity.
6.4.2 Adjust TDS conversion factor in parameter setting P2.4 according to the
data collected during testing and experience. Chart –10 lists some common
use Conductivity and TDS conversion factors. This is for your reference only.
Chart –10 Conductivity and TDS conversion factors
Conductivity of solution
TDS conversion factor
0-100 μS/cm
0.60
100-1,000 μS/cm
0.71
1-10 mS/cm
0.81
10-100 mS/cm
0.94
6.5. Sample test
6.5.1. Rinse conductivity electrode in pure water, allow it to dry, and submerge it in the sample
solution. Stir the solution briefly and allow it to stay in the sample solution until a stable reading is
reached and icon appears on LCD, then get the reading value, which is the conductivity value of
the solution.
6.5.2. Press key to switch to TDS.
Diagram- 8

PC850 Version 1.0
6.5.3. During the process of calibration and measurement, the meter has self-diagnosis functions,
indicating the relative information as below: chart –11.
Chart –11 Self-diagnosis information of conductivity measurement mode
Display Icons
Contents
Checking
Wrong conductivity calibration solution
or the meter recognition of calibration
solution out of range
1. Check whether conductivity calibration
solution is correct.
2. Check whether the meter connects the
electrode well.
3. Check whether the electrode is
damaged.
Press key when measuring value is
not stable during calibration.
Press key after icon appears
During calibration, the measuring value
is not stable for ≥ 3 min.
1. Shake the electrode to eliminate
bubbles in electrode head.
2. Replace with new pH electrode.
6.5.4 Factory default setting
For factory default setting, please refer to parameter setting P2.5 (Item 7.4). With this function, all
calibration data is deleted and the meter restores to the theory value. 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.
6.6. Conductivity electrode maintenance
6.6.1. Always keep the conductivity electrode clean. Before taking a measurement, rinse the
electrode in pure water and better to rinse it again in the sample solution. When submerge the
electrode in solution, stir the solution briefly to eliminate air bubbles and allow it to stay until a stable
reading is reached. For conductivity electrode which is drily stored, soak the electrode in pure water
for 5-10 minutes. Rinse the electrode in pure water after measurement.
6.6.2. The interaction rod of Model 2301T-S conductivity electrode is coated with platinum black to
minimize electrode polarization and expand measuring range. The platinum black coating adopted
our special processing technology which improves the electrode performance and the firmness of
the coating. If the platinum black electrode is stained, gently clean the electrode with soft brush in
warm water containing detergent or alcohol.
7. Parameter setting
7.1. Main menu
In the measurement mode, press key to enter in P1.0, then press to switch to main menu:
P1.0→P2.0→P3.0. Please refer to diagram –9.
P1.0: pH parameter setting menu,

PC850 Version 1.0
P2.0: Conductivity parameter setting menu,
P3.0: Basic parameter setting menu.
7.2. Submenu
7.2.1. In P1.0 mode, press key to enter in 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.
7.2.2. In P2.0 mode, press key to enter in submenu P2.1 of conductivity parameter setting,
then press key to switch among submenu: P2.1→P2.2→P2.3→P2.4→P2.5, see Diagram–9.
7.2.3. In P3.0 mode, press key to enter in submenu P3.1 of basic parameter setting, then
press key to switch among submenu: P3.1→P3.2→P3.3, see Diagram –9.
Diagram –9 Main menu and submenu of parameter setting
P1.1 Select pH standard solution
P1.2 Select resolution
P1.3 Set stability criteria
P1.4 Restore to factory setting
P2.1 Select electrode constant
P2.2 Select reference temp
P2.3 Adjust temperature
compensation factor
P2.4 Adjust TDS factor
P2.5 Restore to factory setup
P3.1 Select temperature unit
P3.2 Automatic power-off setup
P3.2 Automatic lock-up setup
Submenu of pH parameter setting
Submenu of Cond. parameter setting
Submenu of basic parameter setting
Main menu of parameter setting

PC850 Version 1.0
7.3. 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 in P1.0 mode,
then press to enter in P1.1.
2. When press key, USA blinks, press key to select
USA→nIS, press to confirm. USA-USA series; nIS-NIST
series.
3. After confirm parameter, press key to enter in 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 blinks, press key to select 0.01→0.1,
press key to confirm.
2. After confirm parameter, press key to enter in 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 blinks. Press key to select nor→HI→Lo,
press to confirm. Nor –Normal, Hi –High, Lo –Low.
2.After confirm parameter, press key to enter in P1.4 mode, or
press key to return to the measurement mode.
P1.4. –Restore factory setting (No –Yes)
1. Press key, no blinks. 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 don’t select Yes, press key to return to the measurement
mode.
7.4. Submenu of conductivity parameter setting (press key to switch)
P2.1. –Select electrode constant (1.0-10.0-0.1)
1. In P2.0 mode, press key to enter in P2.1 mode, please refer to
the left Diagram.
2. Press key, 1.0 blinks, then press key to select
1.0→10.0→0.1, press key to confirm.
3. After confirm the parameter, press key to enter in P2.2 mode,
or press key to return to the measurement mode.
P2.2. –Select reference temperature (15.0°C-30.0°C)
1. Press key, 25.0°C blinks, then press key to adjust
temperature value 15.0-30.0, press key to confirm.
2. After confirm parameter, press key to enter in P2.3 mode, or
press key to return to the measurement mode.

PC850 Version 1.0
P2.3. –Adjust temperature compensation coefficient
(0.00-9.99%)
1. Press key, 2.00 blinks, press key to adjust temperature
compensation coefficient 0.00 –9.99, press key to confirm.
2. After confirm the parameter, press key to enter in mode P2.4
or press key to return to the measurement mode.
P2.4. –Adjust TDS factor
1. Press key, 0.71 blinks, press key to adjust TDS factor
0.04 –1.00, press key to confirm.
2. After confirm the parameter, press key to enter in mode P2.5
or press key to return to the measurement mode.
P2.5. –Restore factory setting (No –Yes)
1. Press key, no blinks. 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 don’t select Yes, press key to return to the measurement
mode.
7.5. 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 in P3.1 mode, please refer to
the left Diagram.
2. Press key, °C blinks, then press key to select °C→°F, press
key to confirm.
3. When parameter is confirmed, press key to enter in mode P3.2
or press key to return to the measurement mode.
P3.2 –Automatic power-off setup (10→20→30→On)
1. Press key, On blinks, press key to select 10→20→30→On
press key to confirm.
On –turn off automatic power-off; Time unit is minutes.
2.After confirm the parameter, press key to enter in mode P3.3 or
press key to return to the measurement mode.
P3.2 –Automatic lock-up setup (Off→On)
1. Press key, OFF blinks, 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.