BOQU pHG-2091 User manual

SHANGHAI BOQU INSTRUMENT COMPANY WWW.BOQUINSTRUMENT.COM
pHG-2091
Online pH / ORP Meter
User manual
SHANGHAI BOQU INSTRUMENT CO.,LTD
Address:No. 118 Xiuyan Road,Pudong New Area,Shanghai,zip code:201315,China
www.boquinstrument.com|email:[e-mail]|mob:[phone]

SHANGHAI BOQU INSTRUMENT COMPANY WWW.BOQUINSTRUMENT.COM
Content
Foreword................................................................................................................................1
User notice.............................................................................................................................4
Chapter 1 Production introduction...............................................................................5
1.1 Features.......................................................................................................................5
1.2 Technical indexes........................................................................................................5
Chapter 2 Installation........................................................................................................6
2.1 Meter installation.........................................................................................................6
2.2 Electrode installation...................................................................................................7
2.3 Meter wiring................................................................................................................7
Chapter 3 Button operation.............................................................................................9
Chapter 4 Meter display and operation.......................................................................9
Chapter 5 Settings..............................................................................................................11
5.1 System Setting............................................................................................................11
5.2 Signal Setting.............................................................................................................12
5.3 Online Calibration......................................................................................................12
5.4 Remote Setting...........................................................................................................13
5.5 Alarm Setting..............................................................................................................13
5.6 Information Inquiry.....................................................................................................13
Chapter 6 Communication protocol.............................................................................14
Chapter 7 Product maintenance....................................................................................14
Chapter 8 Trouble analysis and recovery methods..................................................16

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Foreword
Thank you very much for your company to buy my company's pH / redox online analyzer.
This manual describes the functions, wiring methods, setting methods, operation methods and
fault handling methods that can be realized by the instrument in detail. Before the instrument
is put into operation, it is necessary to read this manual in detail, to understand the use of the
method and then to carry out specific operations, to avoid unnecessary damage caused by the
wrong operation, if the manual described in the method other than the operation, and
sometimes damage the instrument Provide protection, if it is due to breach of these
precautions arising from the failure and the accident, our company is not responsible.
Please read this manual carefully before using the instrument. Under the premise of full
understanding, must be on the scene of the relevant electrical professionals in order to install
the instrument, operation and maintenance. Incorrect installation or operation can result in
damage to the instrument or personal injury
The company promises to the user, the instrument should be provided when the supply of
hardware, accessories in the material and manufacturing processes are not any flaws. From
the date of purchase of the instrument from the date of calculation, in the warranty period, if
the user received a notice on such defects, the company is indeed defective products for
unconditional free maintenance or free replacement. The company for all products will
guarantee life-long maintenance.
In order to comply with the principles of sustainable development, the Company reserves the
right to modify the performance parameters described in this manual without prior notice.
Reserves the right to revise or revoke this manual without prior notice. When the instrument
changes certain performance parameters may lead to serious accidents, the company must
inform the user in advance. For the improved instrument, the company will have a new
version of the instructions or improved instructions. If there is a deviation from the
description in this manual, please prevail in kind.
No modification of the instrument! Due to unauthorized transformation of the product caused
by the accident, the company is not responsible.

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Instructions used in this manual
Remark
Name
Note
Danger
Failure to take appropriate precautions can result
in serious personal injury, damage to the
instrument, or loss of significant property.
Warning
Remind you of the important information about
the product or the special part of this manual.
Caveat
Be careful to do this, and execution errors can
cause significant problems.
Note
Please read this note carefully, it is very helpful to
operate the instrument correctly.
Danger
Do not use the instrument in flammable and explosive atmospheres or where there
is steam.
The instrument can work normally in general. If the fault of the instrument may
cause serious accident or damage other equipment, need to set the emergency stop
circuit and protection circuit.
Make sure that the supply voltage is consistent with the rated voltage before
running.
In order to prevent electric shock, misuse, display is not normal or measurement
of a larger error, be sure to carry out a good grounding protection.
Must be mine construction facilities: common grounding grid equipotential
grounding, shielding, reasonable wiring, the appropriate use of SPD surge
protector and so on.
Some internal parts with high pressure, non-company or non-I recognized the
maintenance staff, do not open the front panel, in order to avoid electric shock.
Make sure that the power is turned off before performing any inspection to avoid
electric shock.
Check the terminal screws and mounting screws regularly. If they are found loose,
please use them before tightening.
Never allow unauthorized removal, processing, alteration or repair of the
instrument, otherwise it may cause abnormal action, electric shock or fire
accident.

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Please use a dry cotton cloth to wipe the instrument, can not use alcohol, gasoline
or other organic solvents. Beware of a variety of liquid splashed on the
instrument, if the instrument fell into the water, please immediately cut off the
power, or leakage, electric shock and even fire accidents.
Check the grounding protection and fuse status regularly. Do not run if you think
that the protective measures such as earthing protection and fuses are not perfect.
Ventilation holes in the instrument housing must be kept smooth so as to avoid
high temperature failure, abnormal action, shortened life and fire.
Please follow the instructions in this manual, otherwise it may damage the
instrument protection device.
Warning
If you find out if the instrument is damaged or deformed, please do not use it.
Install to avoid dust, thread, iron or other substances into the instrument,
otherwise it will occur abnormal action or failure.
During operation, if you want to modify the configuration, signal output, start,
stop and other operations, should take full account of operational safety, error
operation may lead to instrumentation and equipment failure or even damage.
Parts of the instrument have a certain period of life, in order to ensure long-term
use, be sure to carry out regular maintenance and maintenance.
Scrap the product, according to industrial waste disposal, to avoid pollution of the
environment.

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User Notice
Please observe the operating instructions and precautions in this manual.
The instrument can be operated normally. If the malfunction of the instrument may result in a
major accident or damage to other equipment, the emergency stop circuit and the protection circuit
shall be provided. Otherwise, the Company will not be responsible for any consequences.
The instrument has only one electrode input. When selecting the PH mode, the PH electrode
should be installed. The OPR electrode should be installed in the ORP mode.
In order to make the measurement more accurate, the glass electrode shelf life of one year,
the factory a year later, regardless of whether the use of its performance will be affected,
should be replaced.
The first use of the PH electrode or long-term no use of the PH electrode, must be sink into
3mol/ L of KCL for 24 hours.
Preheat the instrument for about half an hour before performing calibration work.
When measuring, should be washed in distilled water (or deionized water), and filter the
paper to absorb moisture, to prevent impurities into the measured liquid.
In the course of the use of the instrument if the work is abnormal or damaged, please contact
the manufacturer, do not repair themselves.

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Chapter 1 Production introduction
PHG-2091 Online pH / ORP Analyzer is one of the intelligent online chemical analysis
instruments, is a widely used in thermal power, chemical fertilizer, metallurgy, environmental
protection, pharmaceutical, biochemical, food and tap water solution PH value or OPR Value and
temperature of the continuous monitoring.
Continuous monitoring data through the transmission output connection recorder to achieve
remote monitoring and recording, you can also connect the RS485 interface through the
MODBUS-RTU protocol can be easily connected to the computer to achieve monitoring and
recording.
1.1 Features
Board modular design, assembly configuration more convenient.
■ Using 2.4-inch 12864 dot matrix screen
■ Use isolated output, less interference
■ Isolated RS485 communication
■ Can be PH / ORP measurement, temperature measurement, high and lower limit control,
transmission output, RS485 communication
■ Configurable temperature manual, automatic compensation function
■ Can set high and low alarm function, and hysteresis
■ Can be set buzzer, LCD backlight switch function
■ Increase the universal password function
■ Industrial control watchdog to ensure that the instrument does not crash
1.2 Technical indexes
■ Isolated 4-20 mA current output, the maximum load 750Ω, 0.1% FS
■ Measuring range: PH (0-14 pH); ORP (-2000- + 2000 mV)
■ Accuracy: ± 0.03 pH; ± 2mV
■ Resolution: ± 0.01 pH; ± 1mV
■ Stability: ≤ 0.02 pH / 24H; ≤ 3 mV / 24H

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■ Input impedance: ≥10 ^ 12
■ Temperature type: NTC10K
■ Temperature measurement range: 0-99.9 ℃, accuracy: ± 0.5 ℃
■ Temperature compensation: 0-99.9 ℃ manual / automatic
■ RS485 function, compatible with standard MODBUS-RTU communication protocol
■ Power supply: AC220V ± 10%, 50 / 60Hz
■ Alarm relay AC250V, 3A
Chapter 2 Installation
2.1 Meter installation
Please describe the installation method and installation method of this instrument. Be sure to
read this section when installing.
Installation Precautions
The instrument is equipped with relay switch output, generally used for alarm prompts, if the
user will use this function to participate in loop control, if the instrumentation, the instrument is
used to control the instrument, The failure may lead to major accidents or damage to other
equipment, the need to set the emergency stop circuit and protection circuit complement,
otherwise the consequences, the company is not responsible.
This instrument is disk mounted.
Please install indoors, avoid wind and rain and direct sunlight.
In order to prevent the internal temperature rise of the instrument, please install in a well
ventilated place.
When installing this instrument, please do not tilt left and right, as far as possible (can be tilted
<30 °).
Avoid the following places during installation
The area where the sunlight is directly irradiated and the vicinity of the heat instrument.
Work where the ambient temperature exceeds 60 ° C.
Work where the ambient humidity exceeds 85%.
Near the electromagnetic source.

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Mechanical vibration strong place.
The temperature change is easy to condensation place.
Fumes, steam, moisture, dust and corrosive gases.
Installation method
Open a 92.5 * 92.5 mounting hole on the instrument cabinet or mounting panel to insert the
instrument into the mounting hole fixing screw.
2.2 Electrode Installation
Common installation diagram
2.3 Meter wiring
Terminal definition
■ INPUT: Electrode measurement terminal
■ REF: Sensor reference
■ NC: None
■ TEMP2:Temperature compensation 2
■ TEMP1:Temperature compensation 1
■ RS485(A+): RS485 Communication protocol A+
■ RS485(B-): RS485Communication protocol B-
■ 4-20mA(I+): 4-20mA Output +

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■ 4-20mA(I-): 4-20mA Output -
■ AC220V(L): AC220V Zero wire
■ AC220V(N): AC220V Fire wire
■ HC: High limit normally close
■ HO: High limit normally open
■ LC: Low limit normally close
■ LO: Low limit normally open
■ COM: Relay common port
Notice:
To prevent electric shock, make sure that the meter is not energized before connecting the
signal cable.
To prevent fire, use a double insulated wire.
Do not place the live product near the signal terminals, which may cause malfunction.

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Chapter 3 Button operation
Button description
Remark
Name
Function description
Menu
“Monitoring interface” enter into main menu
“Main menu” to exit
Exit
“Monitoring interface” to check alarm status
“Main menu” to exit to the last page
“Calibration” jump over the calibration process
Right
shift
Cycle select the number of parameters
Next
“Main menu” to select relevant menu
Set the state to modify the relevant value
Enter
“Main menu” enter into sub-menu or confirm the modify
Chapter 4 Meter display and operation
Monitoring interface
The instrument is equipped with monochrome dot matrix LCD display with a resolution of 128 *
64.
Use the 【Menu】to enter the password verification screen, input the password and enter into the
main menu screen.

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Use 【ESC】to enter the alarm query screen, query the current alarm settings information.
Monitoring interface of pH value
Monitoring interface of ORP value
Password verification screen
After entering the password, use [ENT] to enter the main menu screen.
Initial password is 0000, you can use the password modification function to change the password.
If you forget your password, please contact us.
----Password----
0000

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Main menu
----Main menu----
1.System Setting
2. Signal Setting
3. Online Calibration
4. Remote Setting
5. Alarm Setting
6. Information inquiry
System Setting: buzzer and backlight settings, password changes and factory settings.
Signal Setting: switching of the electrode type and automatic switching of the warm-up hand.
Online Calibration: Calibration and correction of PH and ORP signals.
Remote Setting: RS485 and current transmission output parameter settings.
Alarm Settings: high alarm and low alarm parameter settings.
Information Inquiry: current version number.
Chapter 5 Settings
5.1 System setting
----System setting----
1. Language
2. Buzzer
3. Backlight
4. Password Modify
5. Factory Setting
Language: Chinese and English switch
Buzzer: Sets the buzzer switch when the alarm is set.
Backlight Setting: set the LCD backlight switch.
Password Modify: change the password and use the new password login.
Factory Setting: return to factory settings.

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5.2 Signal setting
----Signal setting----
1. Electrode Type
2. Temp compensation
Electrode Type: set the electrode type, PH electrode and ORP electrode two types.
Temperature compensation: set the automatic temperature compensation or manual temperature
compensation, the temperature range of 0-99.9 ℃.
5.3 Online Calibration
----Online Calibration----
1. pH Calibration
2. pH Modification
3. ORP Calibration
4. ORP Modification
PH Calibration: enter into PH calibration screen, put the PH electrode into 4.00PH standard
solution firstly, standing for a moment, after the value stable, press the ENT; Then put the PH
electrode into 6.86PH standard solution, standing for a moment, after the value stable, press the
ENT; Finally, put the PH electrode into 9.18PH standard solution, standing for a moment, after the
test is stable, press the ENT, indicating that the calibration is successful , The PH calibration
process finished.
PH correction: The measured PH value can be corrected between 2 PH values.
ORP Calibration: enter into ORP calibration screen, put the ORP electrode into the 86mV
standard solution firstly, standing for a moment, after the value stable, press the ENT; then put the
ORP electrode into 256mV standard solution, Moment, after the value stable, press the ENT,
display calibration is successful, ORP calibration process is finished.
ORP Correction: The measured ORP value can be corrected between 300mV.

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5.4 Remote Setting
----Remote Setting----
1. RS485
2. 4-20mA setting
RS485: Set the address and baud rate of 485 communication.
4-20mA Setting: set 4-20mA output 4mA corresponds to the value and 20mA corresponding
value.
5.5 Alarm Setting
----Alarm Setting----
1. pH High Alarm
2. pH Low Alarm
3. ORP High Alarm
4. ORP Low Alarm
PH High Alarm: when the measured value is higher than the high value set, the high alarm relay
pull, when the measured value is lower than the high value set, the high alarm relay disconnect.
PH Low Alarm: when the measured value is higher than the low value set, the lower alarm relay
pull, when the measured value is lower than the low value set, the low alarm relay off.
ORP High Alarm: when the measured value is higher than the high value set, the high alarm
relay pull, when the measured value is lower than the high value set, the high reported relay
disconnect.
ORP Low Alarm: When the measured value is lower than the low value set, the low alarm relay
pull, when the measured value is higher than the low value set, the low alarm relay off.
5.6 Information Inquiry
----Information Inquiry----
1. Ver Information
Version information: query the current hardware and software version, strong traceability.

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Chapter 6 Communication protocol
The instrument provides standard RS485 serial communication interface, using the international
standard MODBUS-RTU communication protocol, support 03 read to keep the register command.
Register address
The communication data and the register address are as follows:
Communication sample:
The computer sends: 00 03 00 00 00 01 85 DB
PH / ORP meter returns: 00 03 02 02 AE 05 58
Return command comment: 00 is 485 address;
03 is the function code;
02 is the data length of the return PH value: 2 bytes;
02 for the return of the PH value of 686 (hexadecimal high byte);
AE for the return of the value of 686 (hex low byte);
05 58 is the CRC check value;
Chapter 7 Product maintenance
1. pH glass electrode storage, short-term: stored in the pH 4 buffer solution; long-term: stored in
the pH7 buffer solution.
2. pH glass electrode cleaning, glass electrode bulb contamination may make the electrode
response time longer. CCl4 or soap can be used to wipe the dirt, and then immersed in distilled
water for 24 hours and then continue use. When the pollution is serious, can be use 5% HF
Address
Data type
Function
code
Description
Access
permission
0x0000
unsigned
short
0x03
PH value
(Default two decimal places)
Read only
0x0001
unsigned
short
0x03
Temp value
(Default one decimal places)
Read only
0x0002
short
0x03
ORP value
(Signed integer)
Read only

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solution for 10 to 20 minutes, immediately rinse with water, and then immersed in 0.1N HCl
solution for 24 hours and then continue use.
3. Glass electrode aging treatment: the aging of the glass electrode and the gradual change in the
structure of the glue layer. Old electrode response is slow, film resistance is high, slope is low.
Exfoliation of the outer layer with HF can often improve electrode performance. If this method
can be used to regularly remove the inner and outer layers, the electrode life is almost unlimited.
4. The storage of the reference electrode Silver - silver chloride electrode, the best storage solution
is in saturated potassium chloride solution, high concentration of potassium chloride solution can
prevent the silver chloride in the liquid junction precipitation, and maintain the liquid junction in
the work status. This method also applies to the storage of composite electrodes.
5. The reference electrode regeneration reference electrode problems caused by the vast majority
of liquid junction caused by blockage, the following methods can be resolved:
(1) Soaking fluid interface: 10% saturated potassium chloride solution and 90% distilled water
mixture, heated to 60 ~ 70 ℃, the electrode immersed in about 5cm, soak for 20 minutes to 1
hour. This method dissolves the crystallization of the electrode tip.
(2) Ammonia Soaking: When the liquid interface is blocked by silver chloride can be leaching
with concentrated ammonia. The specific method is to clean the electrode, the liquid vent after
immersion in ammonia 10 to 20 minutes, but do not let ammonia into the electrode inside.
Remove the electrode with distilled water to wash, re-add the internal liquid and continue to use.
(3) Vacuum method: the hose to match the reference electrode fluid interface, the use of water
suction pump, suction part of the liquid through the fluid interface, remove the mechanical
blockage.
(4) boiling fluid junction: silver - silver chloride reference electrode liquid interface immersed in
boiling water for 10 to 20 seconds. Note that the next time you boil, the electrode should be cooled
to room temperature.
(5) When the above methods are invalid, you can use sandpaper grinding mechanical method to
remove the blockage. This method may cause the sand under the grinding into the liquid interface.
Causing permanent clogging.

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Chapter 8 Trouble analysis and recovery methods
1. The controller no display?
A: Check whether the power wiring is connected, the power supply is on.
2. Measurement value is bouncing?
A: Check around the frequency converter and other interference equipment, pay attention to
stay away from these interference equipment or do shielding measures.
3. PH instrument can not be calibrated?
A: The standard solution is not properly formulated or the electrode is damaged.
4. After calibrated by standard solution PH4.00, PH6.86, PH9.18, the test is not test?
A: The standard solution may polluted, replace the standard liquid and re-calibration.
5. The measurement value is slow response?
A: The electrode bulb is covered with dirt, the reaction will slow down, according to the type of
pollutants according to the corresponding cleaning method, it’s normal phenomenon in winter.