ATO PH/ORP User manual

PH/ORP
PH/ORP Meter
User Manual

Catalogue
Preface................................................................................................ 2
Notice.................................................................................................. 2
User instructions................................................................................3
Chapter I Brief introduction on product........................................ 4
Characteristics............................................................................4
Technical index...........................................................................5
Chapter II Fixed installation............................................................6
2.1 Instrument installation........................................................ 6
2.2 Electrode installation........................................................... 7
2.3 Instrument wiring................................................................ 8
Chapter III Operation of keys......................................................... 10
Chapter IV Instrument picture and operation ..............................11
Chapter V Configuration setup.......................................................13
System setup..............................................................................13
Signal setup............................................................................... 13
Online calibration ...................................................................13
Teletransmission setup ...........................................................14
Caution setup............................................................................ 15
Information inquiry................................................................. 15
Chapter VI Communication .........................................................16
Chapter VII Product maintenance................................................ 17
Chapter VIII Fault analysis and exclusion................................... 19
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Preface
Thanks for buying the PH tester.
The installation, function, setup, wiring method and operation
instruction is introduced in the manual. Please carefully read the manual
in advance in order to correctly use the instrument. Please properly keep
the instruction at the place where it can be read at any time after read so
as to provide reference during the operation.
Notice
The content is forbidden to copy and publish.
The change of the manual content won’t be exceptionally notified
due to the continuous improvement of the performance and function.
We do our best to ensure the accuracy and completeness of the
content. Please contact us if mistakes and omission exist.
User instructions
Please abide by the operation specification and notes of the
instruction book during the use.
The instrument only has one electrode input end, PH electrode shall
be installed when the PH mode is selected and OPR electrode shall be
installed in the ORP mode.
The warranty period of the glass electrode is 1 year in order to
ensure more accurate measurement, the performance will be affected 1
year after leaving the factory no matter it’s used or not, which shall be
timely exchanged.
The PH electrode of the first time use or it’s not used for a long time
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must be soaked in 3mol/L Potassium Chloride Solution for 24 hours
before the use.
The electric preheating time of the instrument shall be above about
half a minute before the calibration work is performed.
It shall be washed to clean in the distilled water (or deionized water)
during the measurement; the water shall be dried by filter paper so as to
prevent the sundries from being taken in to the test solution.
Please contact the manufacturer if the instrument can’t normally
work or it’s broken during the use, the self-repair is forbidden.
Chapter I Brief introduction on products
The online monitoring PH/ORP value is independently researched
and developed, which is delivered to the monitoring room with
teletransmission by RS485 or current converter so as to record and store.
PH/ORP tester is one of the intelligent on-line chemical analyzers,
which is broadly used in the continuous monitoring on PH value or OPR
value and temperature of thermal power, chemical engineering and
fertilizer, metallurgy, environment protection, pharmacy, biochemistry,
food and tap water as well as other solution.
The teletransmission monitoring and recording of continuous
monitoring data is realized through the converter output connection
recorder, and the monitoring and recording is realized by easily linking to
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the computer with MODBUS-RTU protocol through connecting RS485
interface.
The low voltage DC24V is added according to the water industry
environment and characteristics combined with international power
supply standard.
Characteristics
Board of modular design makes the assembly and configuration
more convenient.
2.4 inch 12864 lattice screen is adopted.
Isolated transmitting output is adopted so as to make the
interference degree smaller.
Isolated RS485 communication is adopted.
The measurement, temperature measurement, top and bottom
limitation control, transmitting output and RS485
communication of PH/ORP is performed.
Function of configurable manual or automatic temperature
compensation.
High and low warning function as well as retardation can be set.
The buzzer and LCD backlight switch function can be set.
The function of all-powerful password is added.
The watchdog of industrial control can guarantee that the
instrument won’t crash.
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Technical index
Isolated transmitting 4-20mA output can be set, the maximum loop is
750Ω, 0.1%FS
Measurement range: PH（0-14 pH）;ORP(-1000-+1000 mV or
(-2000-+2000 mV))
Precision: ±0.02 pH; ±1mV
Resolution ratio: ±0.01 pH; ±1mV
Stability: ≤0.02 pH/24H; ≤3 mV/24H
Input impedance: ≥10^12
Temperature measurement scope: 0-100℃, precision: ±0.5℃, NTC
10K
Temperature compensation: 0-100℃manual/automatic
RS485function, compatible with standard MODBUS-RTU
communication protocol
Power supply: AC220V±10%, 50Hz or DC 24V
Alarm relay: AC250V, 3A
Chapter II Fixed installation
2.1 Instrument installation
The installation site and method of the instrument are explained, the
part shall be carefully read during the installation.
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Notes for installation
The instrument is panel mounted.
It shall be installed inside the building so as to avoid wind and rain
as well as direct sunlight.
Please install it at the place with good ventilation in order to prevent
the internal temperature of the instrument from rising.
Don’t lean to left or right when the instrument is installed, horizontal
installation shall be realized as possible (retroversion<30°).
The following places shall be avoided during the installation
The place that’s exposed to direct sunlight and the vicinity of the
hot tools.
The place where the environment temperature exceeds 60℃
during the work.
The place where the environment humidity exceeds 85% during
the work.
The vicinity of the electromagnetic occurring sources.
The sites with strong mechanical vibration.
The site where the temperature is changed a lot and the moisture
condensation is easily formed.
Places with lots of lampblack, steam, moisture, dust and
corrosive gas.
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——————————————————————————————————————————
7
Installation method
A 91*91 installation hole is opened at the instrument cabinet or
installation panel
The instrument is inserted into the installation hole and the screw is
fixed, refer to the following drawing
2.2 Electrode installation
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①Side wall installation ②Flange mounted at the top ③Pipe installation ④Top installation
⑤Submersible installation ⑥Flow-through installation
The interface must be in 15°oblique angle, or it will affect the normal test and use of the electrode. We won’t be re
sponsible for any results due to this.
Sketch map of the common installation method
2.3 Instrument wiring
Wiring diagram
Definition of the port
INPUT: measuring terminal of the electrode
REF: reference terminal of the electrode
NC: undefined
TEMP2: temperature compensation terminal 2
TEMP1: temperature compensation terminal 1
RS485(A+):RS485 communication interface A+
RS485(B-):RS485 communication interface B-
4-20mA(+):4-20mA output end+
4-20mA(-):4-20mA output end -
AC220V(L) or (DC24V-): AC220V live wire or
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（DC24Vnegative especially special model）
AC220V(N) or （DC24V+）
:AC220V live wire or
（DC24V
positive especially special model）
LO(AL): low alarm
HI(AH): high alarm
Notice
Please confirm that the instrument is not electrified before
connecting the signal line in order to avoid electric shock.
Please use double insulation line in order to avoid fire
disaster.
Please don’t take electric products near to the signal
terminal, which may cause the fault.
Chapter III Operation of keys
Key distribution
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Definition of keys
identification
Name of the
key
Function description
Menu
Enter the menu under “monitoring interface”
Exit the menu under “monitoring interface”
ESC
Check relevant alarm status under the
“monitoring interface”
The relevant up and bottom layer of interface
under the “menu interface” returns to the up
layer
“Calibration interface” presents the
calibration item is skipped
Right
displacement
The digit of recurrent selection parameter
Down
displacement
Relevant menu is selected under the “menu
interface”
Relevant numerical value is modified under
the setup status
ENT
Enter the submenu or confirm modification
under the “menu interface”
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Chapter IV Instrument picture and operation
Monitoring picture
The instrument is equipped with monochrome lattice LCD , the
resolution ratio is 128*64.
Use Menu to enter the picture of password authentication, input
password to enter the picture of the main menu.
Use ESC to enter the alarm inquiry picture so as to inquire the
current alarm set information.
PH monitoring picture
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ORP monitoring picture
Password verification picture
Use the ENT to enter the picture of the main menu after input the
password.
The initial password is 0000, which can be changed by using the
function of password change.
Please contact us if the password is forgotten.
----------------------User Password--------------------
Password: 0000
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Picture of main menu
--- --------------Main Menu----------------
1. System Setting
2. Signal Setting
3. Online Calibration
4. Remote Setting
5. Alarm Setting
6. Information inquiry
System Setting: the setup of buzzer and backlight, password change
and factory reset.
Signal Setting: switchover of electrode type and manual/automatic
switchover of temperature compensation.
Online Calibration : calibration or correction of PH and ORP signal.
Remote setting: parameter setup of RS485 and current transmitting
output.
Alarm setting: parameter of high alarm and low alarm.
Information inquiry: current version number.
Chapter V Configuration setup
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System Setting
----------------System Setting-----------------
1. Buzzer
2. Change Password
3. Factory setting
Buzzer: set the switch of the buzzer during the alarm.
Change Password: change the password and use the new password
to log in.
Factory setting: return to the set before leaving the factory.
Signal Setting
--------------------Signal Setting----------------------
1. Electrode type
2. Temperature compensation
Electrode type: set the type of the electrode, two types of PH
electrode and ORP electrode.
Temperature compensation: set automatic or artificial temperature
compensation, the temperature scope is 0-99.9℃.
Online calibration
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---------------------Online calibration--------------------------
1. PH calibration
2. PH modification
3. ORP calibration
4. ORP modification
PH calibration: after entering the PH calibration picture, firstly put
PH electrode into 4.00 PH standard solution, standing for a moment, after
the reading is stable, press the ENT, then put the PH electrode into the
6.86/ 7.00 PH standard solution, standing for a moment, after the reading
is stable, press the ENT, finally put the PH electrode into 9.18/10.01 PH
standard solution, standing for a moment, after the reading is stable, press
the ENT, after the reading is successfully calibrated, the calibration
process of PH is completed.
PH modification: the measured PH is modified between two PH
value.
ORP calibration: after entering the calibrated picture, firstly put the
ORP electrode into the 86mV standard solution, standing for a moment,
after the reading is stable, press the ENT, then put the ORP electrode into
the 256mV standard solution, standing for a moment, after the reading is
stable, press the ENT, after the reading is successfully calibrated, the
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calibration process of ORP is over.
ORP modification: the measured ORP is modified between 300mV.
Remote setting
--------------------Remote setting---------------------------
1. RS485
2. Current transmission
RS 485: set the address and baud rate of 485 communication.
Current transmission: set the 4mA and 20mA corresponding
value of the 4-20mA output.
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 bigger than the high
alarm pull-on value, the high alarm relay will actuate; when the measured
value is smaller than high alarm cut-off value, the high alarm relay will
disconnect.
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PH low alarm: when the measured value is smaller than the low
alarm pull-on value, the low alarm relay will actuate; when the measured
value is bigger than low alarm cut-off value, the low alarm relay will
disconnect.
ORP high alarm: when the measured value is bigger than the high
alarm pull-on value, the high alarm relay will actuate; when the measured
value is smaller than high alarm cut-off value, the high alarm relay will
disconnect.
ORP low alarm: when the measured value is smaller than the low
alarm pull-on value, the low alarm relay will actuate; when the measured
value is bigger than low alarm cut-off value, the low alarm relay will
disconnect.
Information inquiry
-------------------Information inquiry-----------------
Version information: inquire the current version of hardware, with
strong traceability.
Chapter VI. Communication
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The instrument provides standard RS485 serial communication
interface, adopts international common standard MODBUS-RTU
communication protocol and supports No.3 reading so as to keep the
holding register order.
Address of register
The communication data and register address as the following table:
Communication case
Sent by computer: 00 03 00 00 00 01 85 DB
Returned from PH/ORP table: 00 03 02 02 AE 05 58
Annotation of the return command: 00 is 485address;
03is function code;
02 is the data length of return PH value: 2 bytes;
02 is the 686 of the return PH value (hexadecimal
high bytes);
AE is the 686 of the return PH value
Address
Data type
Function code
Explanation
Access right
0x0000
unsigned
short
0x03
PH value
(default in
two
decimals)
Read only
0x0001
unsigned
short
0x03
Temperature
value (default
in one
decimal)
Read only
0x0002
short
0x03
ORP value
(signed
integer )
Read only
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(hexadecimal low bytes);
05 58 is the checked value of CRC；
Chapter VII Product maintenance
1. The storage of pH glass electrode, short-term: it’s stored at the
buffered solution of pH=4; long-term: it’s stored at the buffered solution
of pH=7.
2. The washing glass electrode spherical bulbs of the pH glass
electrode possibly lengthen the response time of the electrode due to
contamination. CCl4 or soap solution can be used to wipe the dirt, then it
can be continued to use after being soaked in the distilled water for a
whole night. It can be soaked for 10~20 minutes by 5% HF solution when
the contamination is serious, then immediately use water to wash clean,
finally It’s used after being soaked in the 0.1N HCl solution for a whole
night.
3. Treatment of glass electrode aging: the aging of glass electrode is
related to the progressive change of the substratum structure. The
response of the old electrode is slow, the membrane resistance is high,
and the slope is low. The external substratum is etched by hydrofluoric
acid, which can usually improve the electrode performance. If the internal
and external substratum can be regularly cleaned by this method, the
service life of the electrode is almost unlimited.
4. The best storage solution for the storage silver-silver chloride
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