This manual serves to explain the use of the Alpha-pH2000D series pH/ORP controller/transmitter. The manual
functions in two ways, firstly as a step by step guide to help the user operate the instru ment. Secondly, it serves
as a handy reference guide. This instruction manual is written to cover as many anticipated applications of the
Alpha-pH2000D pH/ORP controller/transmitter. If you have doubts in the use of the instrument, please do not
hesitate to contact the nearest Alpha Authorised Distributor.
The information presented in this manual is subject to change without notice as impro vements are made, and
does not represent a commitment on part of Thermo Scientific.
Thermo Scientific cannot accept any responsibility for damage or ma lfunction of the unit due to improper use of
the instrument.
The Controller/ Transmitter shall be installed and operated only in the man ner specified in the Instruction manual.
Only skilled, trained or authorized person should carry out installation, setup and operation of the instrument.
Before powering up the unit, make sure that power source it is connected to, is as specified in the top label.
Failure to do so may result in a permanent damage to the unit.
The unit has live and exposed parts inside. If it has to be opened, make sure that the power to the un it is off and
disconnected.
The unit is Fuse protected. In the event the fuse has to be replaced, use only those as specified in the manual.
The degree of protection against electric shock will be achieved only by observance of the corresponding
3ASSEMBLY AND INSTALLATION.......................................................................................................................................9
T THE VERY BEGINNING ...............................................................................................................................................1
UTTING OUT OF SERVICE /CORRECT DISPOSAL OF THE UNIT.........................................................................................2
ESCRIPTION OF UNIT...................................................................................................................................................3
EASUREMENT AND CONTROL SYSTEM..........................................................................................................................4
2.3.3 LED indicators.......................................................................................................................................................7
2.3.5 Menu overview ......................................................................................................................................................8
OUNTING THE UNIT .....................................................................................................................................................9
IEW ACTUAL ZERO AND SLOPE ...................................................................................................................................15
IEW RELAY SET POINTS .............................................................................................................................................28
ET-POINT AND CONTROL FUNCTION –RELAY 1&RELAY 2..........................................................................................30
ASH FUNCTION –WASH RELAY ................................................................................................................................30
LARM FUNCTION –ALARM RELAY ..............................................................................................................................31
RANSMITTER FUNCTION ............................................................................................................................................31
OLTAGE OUTPUT &HOLD FUNCTION SWITCH ............................................................................................................31
LECTRICAL DATA AND CONNECTIONS.........................................................................................................................31
EPLACEMENT UNIT ...................................................................................................................................................33
ACKAGING /SCOPE OF DELIVERY...............................................................................................................................34
ETURN OF GOODS.....................................................................................................................................................34
UIDELINES FOR RETURNING UNIT FOR REPAIR ............................................................................................................34
AINTENANCE AND CLEANING.....................................................................................................................................34
11.4.1 Control characteristic of Controllers used as limit value switch.....................................................................38
11.4.2 Control characteristic of P-Controllers as proportional controller...................................................................38
11.4.3 Control characteristic of PI-Controllers as proportional integral controller.....................................................38
11.4.4 Control signal of Pulse length Controllers......................................................................................................39
11.4.5 Control signal of Pulse Frequency Controllers...............................................................................................40
11.5 A
PPENDIX 5–ABBREVIATIONS USED IN MENU DISPLAYS...............................................................................................41
Page 6
INTRODUCTION
1.1 At the beginning
We thank you for having purchased the Alpha pH 2000D pH/ORP Controller.
The construction of the pH/ORP Controller employs leading edge technology and complies with safety
regulations currently in force. Notwithstanding this, improper use could lead to hazards for the user or a
third-party, and/or adverse effects on the plant or other equipment. Therefore, the operating
instructions must be read and understood by the persons involved before work is started with the
pH/ORP Transmitter.
This instruction manual identifies safety instructions and additional information by means of the
following symbols:
This symbol draws attention to safety instructions and warnings of potential
danger which, if neglected, could result in injury to persons and/or damage
to property.
This symbol identifies additional information and instructions which, if
The instruction manual must always be stored close at hand, in a place accessible to all people
working with the pH/ORP Controller.
If you have questions, which are not or insufficiently answered in this instruction manual, please
contact your authorized supplier. They will be glad to assist you.
neglected, could lead to inefficient operation and possible loss of
production.
1.2 Intended Use
The Alpha pH 2000D pH/ORP Controllers are intended solely for pH or ORP and temperature
measurement, as described in this instruction manual.
Any other use, or use not mentioned here, that is incompatible with the technical specifications is
deemed inappropriate. The operator is solely responsible for an y damage arising from such use.
Other prerequisites for appropriate use include:
– observing the instructions, notes and requirements set out in this instruction manual.
– observing all local safety regulations concerning safety at work.
– observing all information and warnings in the documentation dealing with the products us ed togeth-
er with the transmitter (housings, sensors, etc.).
– observing the prescribed environmental and operational conditions.
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Page 7
1.3 Safety Instructions
- The Alpha pH 2000D should be installed and operated only by personnel familiar with the
transmitter and who are qualified for such work.
- A defective controller must neither be installed nor put into service.
- The Alpha pH 2000D must only be operated unde r the specified operating conditions (see
section 8).
- The Alpha pH 2000D must not be repaired by the customer.
- The Alpha pH 2000D must only be opened to replace the unit fuse. This work must be
carried out only by personnel familiar with the transmitter and who are qualified for suc h
work. Make sure the mains cable is separated from the power supply before opening the
unit.
- No modifications to the Alpha pH 2000D are allowed. The manufacturer/supplier accepts no
responsibility for damage caused by unauthorized modifications. The risk is borne
entirely by the user.
1.4 Putting Out of Service / Correct Disposal of the Unit
Putting out of service
• First disconnect the unit from the mains, then undo all electrical connections.
• Remove the unit from the wall / panel.
Correct disposal of the unit
When the transmitter is finally taken out of service, observe the local environmental regulations for
correct disposal or send the transmitter to your local distributor, they will take care of proper disposal.
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Page 8
2 Product Description
2.1 Description of Unit
The Alpha pH 2000D is used for measuring pH an d temperature values. The pH values can be m easured using industrial
differential & combination pH sensors. The temper ature values can be measured using 2-wire / 3-wire NTC300 thermistor.
The transmitter is available in a wall mountin g enclosure. The controller / transmitter can be used for applications such as
water treatment and monitoring, galvanic-decontamination, chemical processing, food processing, clean or wastewater
control and neutralization processes.
This transmitter has many user-friendly and safety features which include:
• Push-button for calibration and sensor offset adjustment from the keypad.
• Built-in non-volatile memory to ensure that calibration and other information are not erased if power supply fails.
• Menu-driven program that simplifies set-up.
• Automatic temperature compensation (ATC).
• Manual temperature compensation setti ng without the ATC probe, with independe nt setting for calibration and pr ocess
temperature.
• Two galvanically isolated current outputs 0/4...20mA.
• Two switching contacts as set-point relays.
• 0 to 2000 seconds time delay adjustment on all relays – minimizes false alarms.
• Separately adjustable high and low set-point hysteresis (dead bands) prevent chattering of relays around the set points.
• Three control modes: limit controller, P controller and PI controller (P/PI controller as pulse length or pulse frequency).
• Large dual display LCD for easy reading with clear multiple annunciators, alarm status, operational and error messages.
• Separate alarm relay alerting you to s et point limits ex ceeded for a certain t ime and if the NTC300 thermistor wires ar e
broken or disconnected during the ATC function.
• Wash relay.
• Hold function to freeze output current (0/4...20mA) and release control relays.
• LED indicators signal control activities to visually monitor transmitter status from a distance.
• Protection against electromagnetic interference.
• Back lit and UV light protected LC display.
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Page 9
2.2 Measurement and Control System
A typical measurement system consists of:
• A pH/ORP process controller
• A pH/ORP combination electrode with integrated or separate temperature sensor NTC300
thermistor.
• An appropriate pH or ORP measurement cable
• An immersion, flow or process assembly with or without a potential matching pin (PMP)
• A final control element such as pump or valve
• A chart recorder
Alpha pH 2000D Transmitter
Chart Recorder
Housing and
Sensors
Measurement Cable
0/4 - 20 mA
Power Mains
(80 - 250 VAC)
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Page 10
2.3 Unit Overview
Wall mounting version
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Page 11
A
2.3.1 Display Overview
The LC display shows two alpha-numerical fields for parameters and measured values as well as
various mode and status indicators.
SETUP
MEAS
CAL
READY
HOLD
ERR
2.3.2 Key functions
Key Description
O
pH
pH %
C
TC
mV
O
F
Mode indicators:
MEAS: measurement mode
SETUP: Set-up mode
CAL: Calibration mode
Status indicator:
READY: Visible after successful calibration
HOLD: Unit in “HOLD” mode
ATC: Visible in ATC (Automatic T emperature
Compensation) mode. Not visible in the Manual
Temperature Compensation mode. “ATC” flashes if
the temperature probe is faulty in its ATC mode
ERR: Error indicator
S: Visible in symmetrical measurement mode
Enter Calibration mode (requires access code)
Enter Set-up mode (requires access code)
Access sub functions (parameters) within a function group of Set-up mode
Confirm (store) set-up parameters and numerical values
Start/Confirm calibration in Calibration mode.
Select function group in the Set-up mode.
Set parameters and numerical values (if key is pressed continuously, the setting speed increases).
Control the relays in MANUAL relay operation.
Returns to “Measurement mode” when both keys are pressed simultaneously.
Display limit values for SP1 and SP2 and settings for wash contact in AUTO relay operation.
Toggle between RELAY A, RELAY B or Wash relay in MANUAL relay operation
Switch from AUTO to MANUAL relay operation (requires access code)
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Page 12
2.3.3 LED indicators
Relay indicators
If REL key is pressed the LED (A, B or W) indicates to which Relay (A, B or Wash)
the displayed limit values refer.
Relay mode indicators
Relay status indicators
Auto LED lights if relay operation is set to automatic mode. Manu LED lights if relay
operation is set to manual mode.
This LED lights if limit value is exceeded or the ATC probe fails.
This LED lights green if measured value is within the limit for Relay A or lights red if
measured value exceeds limit.
This LED lights green if measured value is within the limit for Relay B or lights red if
measured value exceeds limit.
This LED lights if cleaning cycle is on.
2.3.4 Security codes
The access to Calibration mode, Setup mode and Manual relay operation mode is protected with
security codes. The security codes are set at the factory and cannot be changed by the user. The
following security codes are used:
Security code Mode Description
000 View only mode to view actual settings
11 Calibration mode to start calibration
22 Setup mode to configure parameters
22
Manual relay operation to switch relay operation mode from automatic
to manual
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Page 13
2.3.5 Menu overview
MEAS
CAL
H
P
°C
ENTER
ENT
CCD “000” = Check calibration parameters (View only mode)
17. 12V output ground 33. pH input, Measure (Red wire)
IMPORTANT: The Alarm relay functions “As OFF under as anctive Lo w” device i.e. it switche
Alarm condition. Therefore the Alarm display device should be connected to the ‘NC’ contacts of
the relay (10 & 11).
NOTE:
a) Switc
b) It shall be in close proximity to the equipment and within easy reach of
h or circuit breaker shall be included in the building installation.
the operator.
c) It shall be marked as the disconnecting device for the equipment.
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Page 16
4 Normal Operation
4.1 Measurement Mode
When the controller/transmitter is powered on, the display first shows all segments briefly, after which
the controller/transmitter automatically enters into the Measurement mode.
Please note: To guarantee accurate readings, the measuring system (transmitter and
sensor) must be calibrated.
MEAS
pH
O
C
The mode indicator “MEAS” at the top of the display indicates that the transmitter is in Measurement
mode. The upper alpha-numerical display shows the measured pH or ORP value, while the lower
display shows the temperature value if the controller is s et for pH measurement, or “ORP” if it is set for
ORP measurement.
The annunciators “pH”, “mV” or “%” at the upper right side of the display indicate the current
measurement mode setting whether the controlling is set for pH, mV or ORP % measurement.
From Measurement mode you can access Calibration mode and Setup mode by pressing the CAL
key or ENT key followed by the corresponding security code. For detaile d information refer to section 5 “Calibration mode” or section 6 “Setup mode”, respectively.
By pressing the REL key in Measurement mode you can view the actual relay set points. By pressing
the MODE key followed by the corresponding security code in Measurement mode you can switch
relay operation mode from automatic to manual.
For detailed information refer to section 7 “Relay Modes”.
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Page 17
5 Calibration Mode
You can access the Calibration mode directly from the Measurement mode b y pressing the CAL key
and entering the Calibration security code “11”. Calibration mode may also be accessed via the Setup
mode (see section 6.1).
1. While in Measurement mode p ress the CAL key (direct access) or ENT key (access via Setup mode).
2. If CAL key was pressed: The display prompts you to enter the calibration security code. Press the ▲ or ▼ key to set the calibration security code to “11”, and then press the ENT key to confirm the calibration
security code.
3. If ENT key was pressed: The display prompts you to enter the security code. Press the ▲ or ▼ key to
set the security code to “22”. Press the ENT key to confirm the security code, and then press the ▲ or ▼ key to select the calibration sub-function.
If configured for pH control, the display shows “CAL PH”. If configured for ORP control, the display
shows “CAL ORP”. To start calibration, refer to the corresponding section (see illustration above).
Note: to exit Calibration mode at any time press the ▲ and ▼ keys simultaneously
(escape). The transmitter returns to the Measurement mode and the old calibration values
remain active. The calibration security code automatically resets from “11” to “000” after the
transmitter returns to Measurement mode.
Note: The calibration is always carried out in the units (pH or mV or %) selected in setup
mode. The pH controller/transmitter allows a 1-point or 2-point calibration.
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Page 18
5.2 pH Calibration
If the unit of measure is in pH (default), then the calibration is also carried out in pH. This transmitter
features a one-point or two-point calibration for pH with five preset buffer sets. Buffer values refer to 25
o
C. A standard pH buffer solution that matches one of these values is required to calibrate the
instrument
.
Two point calibration
SETUP
HOLD
HOLD
CAL
H
P
H
P
HOLD
CAL
H
P
H
P
CAL
H
P
MEAS
CAL
CAL
One point calibration
1. Enter Calibration mode as described in section 5.1. The display shows “CAL PH” (for pH calibration).
Note: If the display reads “CAL ORP”, see section 6.9 for procedures on how to switch from ORP to pH
readings.
2. Press the ENT key to start calibration. T he “CAL” indicator appears at the top of display and the buffer
indicator appears in the bottom corner of the display. The display sho ws the actual pH reading (upper
value) and the buffer value for zero point (lower value). For the offset (zero point) calibration, there are
two values to choose from. They are pH 7.00 or pH 6.86. Using the ▲ and▼ keys, choose the value
that matches with the buffer used.
3. Place the electrode in the first buffer solution. In ATC mode, you must also immerse the temperature
probe in the buffer solution.
4. You can conduct either a one-point or a two-point calibration: Press the ENT for two point calibration or
the CAL key for one point calibration. The electrode indicator and CAL indicator both flash for a fe w
seconds. The controller automatically adjusts the reading to match the buffer value.
5. If one-point calibration was selected, the display will show the zero point in the lower section of the
display and the slope (default or using previous two-po int calibration) in the upper section of the display.
Proceed to step 7 after zero point display. If two-point calibration was selected, the lower section of the
display will now show its next lower “pH” buffer. Use ▲ and ▼ keys to select the second buffer from one
of these preset value: - pH 1.68, pH 4.01, pH 9.00, pH 9.18 and pH 10.01. Remove the electrode from
the first buffer, wash and then immerse it into the second buffer. Press the ENT key, the electrode
indicator and CAL indicator will flash for a few seconds. The controller adjusts the reading to the second
buffer.
6. After calibrati ng the second buffer value, the controller will automatically display the slope in the upper
and the zero point in the lower section of the display.
Note: You can also view the values for zero point and slope without calibration (see section 5.5 for
instruction). The zero point and slope are pre-determined after each calibration.
7. Press the ENT key to return t o the Measurement mode.
Note: If you entered the Calibration mode from the Setup mode, the controller will return to the setup menu.
Note: If there is a calibration error, the controller displays “CAL ERR”. If this happens, push
both ▲ and ▼ keys (escape) to restart the calibration beginning from Step 1.
H
P
O
C
atc
Note: When calibrating with manual temperature compensation, the controller automatically
changes from the preset process temperature to the calibr ation temperature. After leaving the
Calibration mode, the controller switches back to process temperature (for setting the
calibration temperature and the process temperature, see Section 6.3)
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Page 19
5.3 ORP-mV Calibration
If controller is configured for ORP-mV measuring you can perform a one-point calibration.
CAL
HOLD
CAL
255
255
mV
HOLD
250
255
CAL
mV
MEAS
R.mV
250
CAL
1. Enter Calibration mode as described in section 5.1. The display should read “CAL ORP”.
Note: If the display reads “CAL PH”, see section 6.9 for procedures on how to switch from pH
to ORP-mV readings.
2. Place sensor in the ORP solution.
3. Press the ENT ke y to start calibration. The “CAL”, buffer and electrode indicator appears on the displa y.
The upper and lower display shows the current mV output of the electrode without any offset adjustment.
4. Press the ▲ or ▼ key to adjust the upper display mV va lue to match your exact reading.
5. Press the ENT key (or CAL key) to confirm. The con troller calculates the correction factor and returns to
the Measurement mode. The “R.mV” annunciator (Relative mV) will be shown on the di splay indicating
that the value displayed is the relative mV value of the default measurement.
5.4 ORP -% Calibration
If controller is configured for ORP-% measuring you can perform a cali bration at t wo points using a l ow
concentration sample (20%) and a high concentrate sampl e (80%). To calibrate the controller for ORP
%:
CAL
1. Enter Calibration mod e as described in section 5.1. The display should read “CAL ORP”.
Note: If the display reads “CAL PH”, see section 6.9 for procedures on how to switch from pH
to ORP-mV readings.
2. Press the ENT key to start calibration. The display prompts you to place the sensor in the high
concentration sample (relative value of 80%).
3. Place sensor in high concentration sample, then press the ENT key (or CAL key). The electrode and
CAL indicators flash. The unit automatically adjusts its reading to match the solution value.
4. The display prompts you to place the sensor in the low concentration sampl e (relative value of 20%).
Remove the electrode from the first standard, wash it well and then immerse it in the 20% standard.
5. When the display stabilizes pr ess the ENT key (or CAL key). The electrode and “CA L” i ndic ator flashe s
and the controller adjust its display to the 20% relative value and exits to the Measurement mode.
Note: If there is a calibration error, the controller displays “CAL ERR”. If this happens, push
both ▲ or ▼ keys (escape) to restart the calibration beginning from Step 1.
HOLD
CAL
C.1
%
HOLD
CAL
CAL
C.2
%
MEAS
59.0
CAL
%
Note: If you stop calibration after entering the first value, or if calibration is defective, the
controller will use its original calibration data.
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Page 20
5.5 View actual zero and slope
MEAS
CAL
ATC
H
P
O
C
ENT
CAL
ENT
pH
1. While in Measurement mode press the CAL key. The display will prompt you to enter a security code.
Leave the security code at “000” (view only mode).
2. Press the ENT key.
The display shows the slope in mV (upper value) and the pH reading at 0 mV (zero point, lower value).
Note: If no key is pressed for 30 seconds the transmitter automatically returns to the
Measurement mode.
3. Press the ENT key to return t o the Measurement mode.
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Page 21
6 Setup Mode
6.1 Enter Setup mode
In the Setup mode the transmitter can be configured to your individual requirements.
1. While in Measurement mode p ress th e ENT key.
MEAS
pH
O
C
ENTER
2. The display prompts you to enter the security code. Set the security code with ▲ or ▼ key
to:
ENT
− “SCD 22” if you want to change parameter settings
− “SCD 000” if you want to view only parameter settings (view only mode)
3. Press the ENT key.
ENTER
ENT
SETUP
HOLD
ENTER
ENT
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
ENTER
ENTER
ENTER
ENTER
ENTER
ENTER
ENT
Temperature settings
see section 6.3
ENT
Relay A (set point 1) settings
see section 6.4
ENT
Relay B (set point 2) settings
see section 6.4
ENT
Controller settings
see section 6.5
ENT
Current output 1 settings
see section 6.6
ENT
Current output 2 settings
see section 6.7
SETUP
HOLD
SETUP
HOLD
ENTER
ENTER
ENT
Wash contact settings
see section 6.8
ENT
Unit settings
see section 6.9
SETUP
HOLD
ENTER
ENT
Calibration
see section 5
Note: Note: to exit Setup mode at any time press the ▲ and ▼ key simultaneously
(escape). The transmitter returns to the Measurement mode.
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Page 22
6.2 Electrode Offset (OFS) sub-function
The electrode offset sub-function is only available if the transmitter is configure d for pH measur ing. Use
this sub-function to set an offset that corrects the readings without removing the electrode from t he
control system. The setting range is ± 120 mV.
The transmitter will add or subtract the offset value from the measuring pH and display the corrected
value. However, if you need to offset the value beyond the average offset you would expect in your
application type, consider a full calibration or even electrode replacement.
1. Take a sample from the system. Record the controller’s pH read ing at the time you take the sample.
2. Measure the pH value of you r sample using a calibrated pH tester, hand-held meter, or bench meter.
Record the correct pH value.
3. Select the “OFS” sub-function, and then press the ENT key.
SETUP
HOLD
SETUP
HOLD
H
P
H
P
4. The display shows the current measured pH value (lower section of the display) and the current offset
value (up per section of the display). Press the ▲ or ▼ key to adjust the pH value noted in Step 2. As the ▲ and▼ keys are being pressed to a djust the pH value, the offset value also changes. Press the
ENT key to confirm the new offset value.
5. Continue with additional Setup procedures, or return to the Measurement mode by pressing the ▲ and
▼ keys (escape) simultaneously.
Note: The offset value is reset during full calibration. See section 5 for full calibration
instructions.
Note: The offset sub-function is blanked out during ORP operation.
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A
6.3 Setting temperature (Set °C°F) sub-function
SETUP
HOLD
HOLD
3
ENT
3
ENT
O
C
1
SETUP
ENT
HOLD
O
C
2
SETUP
HOLD
O
SETUP
ENT
HOLD
SETUP
F
ENT
SETUP
HOLD
SETUP
HOLD
4
ENT
5
SETUP
HOLD
6
ENT
O
C
TC
1. Select the “SET °C°F” sub-function, then press the ENT key.
2. Selecting temperature un it: press the ▲ or ▼ key to select the desired temperature unit “°C” or “°F”.
Press the ENTER key to confirm your selection.
3. Enable/disable ATC mode: press the ▲ or ▼ key to enable (ATC ON) or disable (ATC OFF)
automatic temperature compensation. Press the ENT key to confirm your selection.
−ATC disabled (ATC OFF):
For manual temperature compensation you can set the process and calibratio n temperatures.
This allows calibration at a temperature other than the process temperature. Example: setting a
calibration temperature of 25°C lets you calibrate using standard solutions at 25°C, even if your
process temperature is different from 25°C.
4. Setting the process temperature: press the ▲ or ▼ key to adjust the process temperature (upper
value, setting range: –10.0 to 125.0°C / 14.0 to 257.0 °F). Press the ENT key to confirm process
temperature.
5. Setting the calibration temperature: press the ▲ or ▼ key to adjust the calibration temperature
(upper value, setting range: – 10.0 to 125.0°C / 14.0 to 257.0 °F). Press the ENT key to confirm the
calibration temperature.
−ATC enabled (ATC ON):
6. Setting the temperatur e offset: The display shows the current temperature offset (upper value) and the
temperature currently measured (lower value). Compare the current temperature displayed on the
transmitter to a thermometer known to be accurate. Note the correct temperature value. Press the ▲ or ▼ key to adjust the lower value. The upper number indicates the offset value. You can offset the
temperature by up to ±10°C/±18°F. Press the ENT key to confirm your setting.
Continue with additional Setup procedures, or return to the Measurement mode by pressing the ▲ and
▼ key (escape) simultaneously.
ENT
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Page 24
6.4 Control Relay A / Relay B (SP1/SP2) sub-function
The SP1 sub-function determines the operating parameters for Relay A; while SP2 defines the
operating parameters for Relay B. Since these groups have the same set-up parameters, they are
described together.
SETUP
HOLD
1
ENT
SETUP
HOLD
2
pH
ENT
SETUP
HOLD
3
SETUP
ENT
HOLD
4
pH
ENT
3
SETUP
SETUP
HOLD
HOLD
5
SETUP
ENT
HOLD
hi
ENT
6
ENT
1. Select the “SP1” (Relay A) or “SP2” (Relay B) sub-function, then press the ENT key.
2. Setting set point value: press the ▲ or ▼ key to enter the val ue for set point 1 (set point 2) at which
your controller will activate. Press the ENT key to confirm your setting.
3. Selecting relay function: press the ▲ or ▼ key to select the desired relay function (“LO”= low or “HI”=
high). Press the ENT key to confirm your selection.
Note: This parameter lets you choose the relay function. Select “LO” to activate the relay
when the pH/ORP value undershoots the set point; select “HI” to activate the relay when
the value overshoots the set point. SP1 and SP2 can be selected as “Lo/Lo”, “Lo/Hi”,
“Hi/Lo”, or “Hi/Hi”.
4. Setting a hysteresis value: press the ▲ or ▼ key to select the desired hysteresis (setting range: 0.1 to
1.0 pH, 10 to 100mV or 1 to 10%) for set point 1 (set point 2). Press the ENT key to confirm your setting.
Note: Hysteresis prevents rapid contact switching if your value is fluctuating near the set
point. Please refer to Appendix 3 for a graphical representation of the hysteresis.
Example: You have set your high set point at pH 10.0 and your hysteresis value at pH 0.5. If your
measured value overshoots pH 10.0, the controller’s relay activates. The actions of the ext ernal device
will cause the solution’s pH to drop. The relay will deactivate, when the pH value drops below 9.5 pH.
5.Setting the on-delay time lag: press the ▲ or ▼ key to enter the on-delay time for set point 1 (s et
point 2). The controller will delay activation of the relay for the number of seconds (0 to 2000 seconds)
you select. Press the ENT key to confirm your setting
.
Note: You can set a time delay for each relay, which stops the relay from switching on the
moment the set point is exceeded. This controller lets you set a 0 to 2000 seconds time
delay before your relay activates.
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Page 25
6. Setting the off-delay time lag: p ress the ▲ or ▼ key to enter the off-delay time for set point 1 (set
point 2). Your controller will delay deactivation of the relay for the number of seconds (0 to 2000 second s )
you select. Press the ENT key to confirm your setting.
Note: You can set a time delay for each relay, which stops the relay from switching off the
moment the value reaches the set point and hysteresis. This controller lets you set a 0 to
2000 seconds time delay before your relay deactivates.
Continue with Setup mode procedures, or return to Measurement mode by pressing the ▲ and ▼ keys
simultaneously (escape).
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Page 26
6.5 Controller (CNTR) sub-function
The CNTR sub-function determineshe controller’s parameters.
SETUP
HOLD
ENT
SETUP
HOLD
SETUP
HOLD
ENT
ENT
SETUP
HOLD
SETUP
HOLD
ENT
SETUP
HOLD
SETUP
HOLD
%
ENT
ENT
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
ENT
ENT
ENT
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
ENT
ENT
ENT
SETUP
HOLD
%
ENT
SETUP
HOLD
ENT
SETUP
HOLD
ENT
1. Select the “CNTR” sub function, then press the ENT key.
- 21 -
Page 27
2. Selecting the controller type: press the ▲ or ▼ key to select the suit able controller type:
− OFF = controller off
Use control Off to operate controller as a monitor only or to prevent relays from switching.
− L.CT = limit value control (on/off control).
Use limit control with pumps or valves for fast response
− P/PI = proportional/integral control
Use proportional control to operate your pumps smoothly or for precise control of prop ortioning
valves. Use PI controller to eliminate steady state error.
Note: please refer to Appendix 4 for detailed information on controller settings.
Press the ENT key to confirm your selection.
− If the controller is set to limit value control (L.CT):
3. Selecting the relay status under Non-Alarm condition: press the ▲ or ▼ key to choose the desired
relay status (de-energized = “DEEN” or energized = “EN”). Press the ENT key to confirm your selection.
− If the controller is set to proportional control (P/PI):
4. Selecting the proportional controller type: press the ▲ or ▼ key to select the suitable controller type
(“PLC” = pulse length control, “PFC” = pulse frequency control). Press the ENT key to confirm your
selection.
− If the proportional controller type is set to pulse length control (PLC):
5. Selecting the relay status under Non-Alarm condition: press the ▲ or ▼ key to choose the desired
relay status (de-energized = “DEEN” or energized = “EN”). Press the ENT key to confirm your selection.
6. Setting the proportional range: Press the ▲ or ▼ key to set the proportional range (setting range: 10
to 500%). Press the ENT key to confirm your setting.
7. Setting the pulse length: Press the ▲ or ▼ key to set the pulse length (setting range: 0.5 to 20
seconds). Press the ENT key to confirm your setting.
8.Setting the integral action time: Press the ▲ or ▼ key to set the integral action time (setting range:
0.0 to 999.9 minutes). Press the ENT key to confirm your setting
− If the proportional controller type is set to pulse frequency control (PFC):
9. Selecting the relay status under Non-Alarm condition: press the ▲ or ▼ key to choose the desired
relay status (de-energized = “DEEN” or energized = “EN”). Press the ENT key to confirm your selection.
10. Setting the proportional range: press the ▲ or ▼ key to set the proportion al range (setting ran ge: 1 0
to 500%). Press the ENT key to confirm your setting.
11. Setting the pulse frequen cy: press the ▲ or ▼ key to set the pulse frequency (setting range: 60 to
120 pulses per minute). Press the ENT key to confirm your setting.
12. Setting the integral action time: press the ▲ or ▼ key to set the integral action time (setting range:
0.0 to 999.9 minutes). Press the ENT key to confirm your setting.
Continue with Setup mode procedures, or return to Measurement mode by pressing the ▲ and ▼ keys
simultaneously (escape).
.
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Page 28
6.6 Current Output 1 sub-function
In this sub-function you set the current output range of the transmitter for pH or ORP values.
SETUP
HOLD
cur.1
1
ENT
SETUP
HOLD
SETUP
HOLD
2
ENT
2
ENT
SETUP
HOLD
SETUP
HOLD
3
pH
ENTENT
3
pH
ENT
SETUP
HOLD
SETUP
HOLD
4
pH
4
pH
ENT
SETUP
HOLD
SETUP
HOLD
5
ENT
5
1. Select the “CUR.1” sub-function, and then press the ENT key.
2. Selecting the output type: press the ▲ or ▼ key to select the desired output t ype: 0-20 mA or 4-20
mA. Press the ENT key to confirm your selection.
3. Setting the pH or ORP value at which the transmitter outp ut will be 4 mA (or 0 mA): press the ▲ or ▼ key to set the pH or ORP value to be equivalent to 4 mA or 0 mA, respectively. Press the ENT key
to confirm your setting.
4. Setting the pH or ORP value at which the tran smitter output will be 20 mA: press the ▲ or ▼ ke y
to set the pH or ORP value to be equivalent to 20 mA. Press the ENTkey to confirm your setting.
5. Selecting out of range curren t: Press the ▲ or ▼ key to switch “CU22” on or off. If “CU22” is on, the
output signal will jump to 22 mA when the measured pH and ORP value is below or above the values set
in points 3 & 4 above. Press the ENT key to confirm your setting.
Note: the “CU22” setting (on/off) of current output 1 applies to current output 2 as well.
Continue with Setup mode procedures, or return to Measurement mode by pressing the ▲ and ▼ keys
simultaneously (escape).
- 23 -
Page 29
6.7 Current Output 2 sub-function
In this sub-function you set the current output range of the transmitter for temperature values.
1
SETUP
HOLD
cur.2
2
SETUP
ENT
HOLD
2
SETUP
HOLD
ENT
ENT
SETUP
HOLD
SETUP
HOLD
3
ENT
o
c
3
ENT
o
c
SETUP
HOLD
SETUP
HOLD
4
ENT
o
c
4
o
c
ENT
1. Select the “CUR.2” sub-function, then press the ENT key.
2. Selecting the output type: press the ▲ or ▼ key to select the desired output t ype: 0-20 mA or 4-20
mA. Press the ENT key to confirm your selection.
3. Setting the temperature value at which the transmitter output will be 4 mA (or 0 mA): press the ▲ or ▼ key to set the temperature value (setting range: -10.0 to 110.0 °C or 14 to 230 °F for NT C300
thermistor) to be equivalent to 4 mA (or 0 mA). Press the ENT key to confirm your setting.
4. Setting the temperatur e value at which the transmitter output will be 20 mA: press the ▲ or ▼ key
to set the temperature value (setting range: 0.0 to 110.0 °C or 32 to 230 °F for NTC300 thermistor) to be
equivalent to 20 mA. Press the ENT key to confirm your setting.
Continue with Setup mode procedures, or return to Measurement mode by pressing the ▲ and ▼ keys
simultaneously (escape).
- 24 -
Page 30
6.8 Wash relay (WASH) sub-function
In this sub-function you set the parameters for the wash relay.
SETUP
HOLD
1
ENT
SETUP
HOLD
SETUP
HOLD
2
ENTENT
2
ENT
SETUP
HOLD
SETUP
HOLD
3
3
ENT
SETUP
HOLD
4
ENT
SETUP
HOLD
5
off
1. Select the “WASH” sub-function, and then press the ENT key.
2. Enabling/disabling wash function: press the ▲ or ▼ key to enable (WASH ON) or disable (WASH
OFF) wash function. Press the ENT key to confirm your selection.
3. Selecting the relay status condition: press the ▲ or ▼ key to choose desired relay status (deenergized = “DEEN” or energized = “EN”). Press the ENT key to confirm your selection.
4. Setting the wash inter val in hours: Press the ▲ or ▼ key to set the desired wash interval (setting
range: 0.1 to 200.0 hours). Press the ENT key to confirm your setting.
5. Setting the wash duration in seconds: Press the ▲ or ▼ key to set the desired wash duration
(setting range: 1 to 2000 seconds). Press the ENT key to confirm your setting.
ENT
Note: During wash cycle the transmitter is set to HOLD. For safety reasons, the HOLD
function is activated 5 seconds prior and deactivated 10 seconds after the wash cycle.
Continue with Setup mode procedures, or return to Measurement mode by pressing the ▲ and ▼ keys
simultaneously (escape).
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Page 31
6.9 Configuration (CNFG) sub-function
In this sub-function you configure the transmitter to suit your requirements.
SETUP
HOLD
3
1
ENT
SETUP
HOLD
2
SETUP
ENT
HOLD
ENT
SETUP
HOLD
4
SETUP
ENT
HOLD
5
ENT
SY
4
SETUP
SETUP
HOLD
2
ENT
HOLD
mV
ENT
SY
4
SETUP
HOLD
SY
%
ENT
SETUP
HOLD
SETUP
HOLD
6
6
ENT
ENT
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
7
7
7
ENT
ENT
MEAS
pH
O
C
ENT
1. Select the “CNFG” sub-function, and then press the ENT key.
2. Enabling/disabling the display backlight: press the ▲ or ▼ key to switch display backlight on (BKL T
ON) or off (BKLT OFF). Press the ENT key to confirm your selection.
3. Setting the backlight intensity (appears only If backlight is on): press the ▲ or ▼ key to set backlight
intensity (setting range: minimum 1 to maximum 4). Press the ENT key to confirm your setting.
4. Selecting the unit of measurem en t: press the ▲ or ▼ key to select measurement mode:
- “PH SY” = pH measurement with symmetrical input
- “ORP mV SY” = ORP-mV measurement with symmetrical input
- “ORP % SY” = ORP-% measurement with symmetrical input
- Press the ENT key to confirm your selection.
5. Setting the alarm delay time in seconds: press the ▲ or ▼ key to set the alarm delay time (setting
range: 0 to 2000 seconds). Press the ENT key to confirm your setting.
Note: With this parameter you set the delay before the alarm relay activa tes when the set
point has been exceeded.
6. Selecting the alarm contact type: pre ss the ▲ or ▼ key to select the alarm contact type:
“STDY” = steady contact
−
− “FLET” = fleeting (single pulse) contact
Press the ENT key to confirm your selection.
- 26 -
Page 32
Note: With this parameter you select whether the alarm contact will operate as a steady
contact or a fleeting (single pulse) contact. Pulse contact closing time is 1 second.
7. Resetting the transmitter settings to factory defaults: The display shows “NO DEF”. Press the ▲ or ▼ key to select:
− “NO DEF” = keeps old values active, when confirmed with ENT key
− “CAL DEF” = resets all calibrations to factory defaults, when confirmed with ENT key
− “FCT DEF” = resets all settings to factory defaults, when confirmed with ENT key
Press the ENT key. The selected function will be executed and the trans mitter returns a utomaticall y t o
the Measurement mode.
Continue with Setup mode procedures, or return to Measurement mode by pressing the ▲ and ▼ keys
simultaneously (escape).
6.10 Calibration (CAL) sub-function
The calibration procedure in Setup mode is identical to the procedur e in the Calibration mode (see
section 5). The only difference is that the transmitter remains in Setup mode (instead of Measurement
mode) after calibration is completed.
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Page 33
7 Relay Modes
You can control devices connected to Relay A, Relay B or wash relay via the front panel of the
transmitter. In Automatic mode, the transmitter’s set point values activate the relays. In
Manual mode, you can manually turn “on” and “off” the control devices connected to the relays.
7.1 View relay set points
To view relay set points, the relay mode must be set to automatic (standard mode after switch-on, relay
mode LED “Auto” lights).
While in Measurement mode press the REL key.
pH
The display shows the set point value for Relay A and LED “A” lights.
pH
After two seconds the display shows the set point value for Relay B and
LED “B” lights).
2
off
After two seconds the display shows the status of the Wash relay and LED
“W” lights. If Wash relay is “off” the display shows “WASH OFF”. If Wash
relay is “on” the wash interval time and wash duration is displayed.
After an additional two seconds the transmitter will return to Measurement
mode.
- 28 -
Page 34
7.2 Manual relay mode
In manual relay mode, you can manually turn “on” and “off” the control devices connected to Relay A,
Relay B or Wash relay.
1. While in Measurement mode p ress th e MODE key.
2. The display prompts you to enter the security code. Press the ▲ or ▼ key to set security code to “22”.
3. Press the ENT key. The Manual relay mode is activated and the relay mode LED “Manu” lights.
Note: Pressing ENT key at a value other than “22” will cause the transmitter to revert to
Measurement mode, and the relays will remain in automatic mode.
4. Press the REL key to select either Relay A, Relay B or Wash relay. The corresponding LED (A, B, or W)
turns to red.
The manual control options now available depe nd on the control type (limit, pulse frequency, or puls e
length) you selected and set in section 6.5.
SETUP
HOLD
SETUP
HOLD
SETUP
HOLD
off
off
o
pH
pH
pH
If you selected Limit control: The display shows the current measured value
and “OFF” or “ON” depending on the relay status of the currently selected
relay.
If you selected Pulse length control: The display shows the current
measured value (upper value) and the on time as a percentage of the
current duration set in the CNTR sub-function in setup mode (lower value).
If you selected Pulse frequency control: The display shows the current
measured value (upper value) and the pulse frequency (lower value).
o
5. Press the ▲ or ▼ key to change the Relay on/off status, pulse length, pulse frequency or wash function.
The relay status LED at the right of the transmitter will also change from Red to Green.
Note: Note: If you wish to manually change the status of relays, press the REL key at this
point and repeat step 5 for the other two relays. The relay(s) will remain under manual
control while you are setting a relay.
6. Press the MODE key to return to Measurement mode. The relays are now back to automatic control.
- 29 -
Page 35
8 Technical Specifications
8.1 General Specification
(a) pH
pH Measuring Range -2.00 to 16.00 pH
Resolution 0.01 pH
Accuracy ± 0.01 pH
(b) mV
mV Measuring Range -1000 to 1000 mV
Resolution 1 mV
Accuracy ± 1 mV
(b) mV percentage
Percentage mV Measuring Range 0 to 100% (for -100 to 100 mV)
Resolution 0.1%
Accuracy ± 0.2 % (or ± 1 mV)
(c) Temperature
Temperature measuring range -10.0 to +110.0 oC or +14.0 to +230.0 oF for NTC300
8.2 Set-point and control function – Relay 1 & Relay 2
Function Switchable
- Selection in Control (CNTR) function of Setup
(a) Off
The control function of the controller is off SP1 & SP2 function will not appear in setup when Off is
(b) Limit Control & P/PI Control
Relay contact selection for active mode Energise (EN) or
Set Point 1 (SP1) -2.00 to 16.00 pH or 0 to 100% or -1000 to 1000mV
Set Point 2 (SP2) -2.00 to 16.00 pH or 0 to 100% or -1000 to 1000mV
Active mode selection (for SP1 & SP2) LO (Relay is active when measured value < set point)
Hysteresis (for SP1 & SP2) 0.1 to 1 pH or 1 to 10.0%/ 10 to 100 mV
On (pickup) Delay (for SP1 & SP2) 0 to 2000 seconds
Off (Dropout) Delay (for SP1 & SP2) 0 to 2000 seconds
(c) P/PI Control only
Proportional Range 10 to 500 %
Integral Action Time (IAT) 0.0 to 999.9 minutes
(c) (1) Pulse Length Control (PLC)
Pulse Length 0.5 to 20.0 seconds
(c) (2) Pulse Frequency Control (PFC)
Pulse Frequency 60 to 120 pulses / minutes
Contact Outputs Two SPST relays
Switching Voltage / Current / Power Max 250VAC / Max 3A / Max 600VA
Off
Limit Control
P/PI Control (Pulse length / Pulse frequency)
selected in CNTR function to off mode
De-energise (DEEN)
HI (Relay is active when measured value > set point)
8.3 Wash Function – Wash Relay
Relay contact selection for active mode Energise (EN) or
De-energise (DEEN)
Wash Cycle Interval 0.1 to 200.0 hours
Wash Duration 1 to 2000 seconds
Contact Outputs One SPST relay
Switching Voltage / Current / Power Max 250VAC / Max 3A / Max 600VA
- 30 -
Page 36
8.4 Alarm Function – Alarm Relay
Alarm Delay 0 to 2000 seconds
Alarm control Steady or Fleet (pulse)
Contact Outputs One SPDT relay
Switching Voltage / Current / Power Max 250VAC / Max 3A / Max 600VA
8.5 Transmitter Function
(a) Current Output 1 – pH/mV Proportional to pH/mV measured
Current output selection 4 – 20mA or 0 – 20mA
pH/mV value for 0 or 4mA current -2.00 to 16.00 pH or 0 to 100% or -1000 to 1000mV
pH/mV value for 20mA current -2.00 to 16.00 pH or 0 to 100% or -1000 to 1000mV
CU22 function
(b) Current Output 2 - Temperature Proportional to Temperature measured
Current output selection 4 – 20mA or 0 – 20mA
Temperature value for 0 or 4mA current -10.0 to +100.0oC or +14.0 to +212.0oF for NTC300
Temperature value for 20mA current 0.0 to +110.0oC or +32.0 to +230.0oF for NTC300
On - 22mA current output for over range or under range or if
outside zoom setting
Off
- 0 or 4 mA current output for under range or below lower
zoom setting
- 20mA current output for over range or above upper zoom
setting
8.6 Voltage Output & Hold Function Switch
+12 V Output 11.5 to 12.5 V Output - Max 50 mA
Hold Function Switch Hold function to freeze output current (0/4...20mA) and release
control relays
8.7 Display
LCD UV coat, backlit 14 segments display with symbols for status
information
Back light On/Off selectable with four levels of brightness control
8.8 Power Supply
Input 80 to 250VAC/DC, 50/60Hz, Approximately 10VA
Main Fuse 315mA Time Delay, 250V, Bussmann BK/GDC-315mA
Pollution Degree 2
Transient Voltage Category II
Connector 5-pin scre w terminal
8.9 Electrical data and Connectio n s
pH/mV Input 8-pin Screw Terminal (3.5mm pitch)
Temperature Input 8-pin Screw Terminal (3.5mm pitch)
Relay 1, Relay 2, Wash Relay & Alarm Relay 9-pin Screw Terminal (7.62mm pitch)
Current Output 1, Current Output 2, 12V output &
Hold function switch
Connection terminal 5-pin, 8-pin, 9-pin & 13-pin terminal connectors
8.10 Mechanical Specifications
Dimensions (W x H x D) - Wall Mount 144 x 144 x 111.5 mm
Weight - Wall Mount 950g (unit) / 1100g (Packed)
Environmental Rating - Wall Mount NEMA 4X, IP65
Emitted Interference EN 61326
Immunity to Interference EN 61326
8.12 Environmental Conditions
Ambient Temperature operating range 0 to 40 oC
Maximum Relative Humidity 80% up to 31 oC decreasing linearly to 50% at 40oC
- 32 -
Page 38
9 Accessories
9.1 Replacement Unit
Product Description Eutech Instruments Order Code
Alpha pH 2000 Controller / Transmitter, wall mount version EC-PHCTP2000D
9.2.1 Assembly Accessories
Product Description Eutech Instruments Order Code
pH Differential Electrode with NTC300 thermistor
ORP Differential Electrode with NTC300 thermistor
Note: Above pH/OR electrodes can withstand a pressure up to 6 bar pressure. These
electrodes have integral 3m measuring cable.
ECFP21A1A1
ECFR21A1A1
Note: Please contact your authorised distributor or dealer for the prices of extension measuring cables
and other accessories like tee joints, electrode assembly, and calibration solutions.
- 33 -
Page 39
10 General Information
10.1 Warranty
Eutech Instruments/Oakton Instruments warrant this product to be free from significant deviations in
material and workmanship for a period of one year from the date of purchase. If repair is necessar y
and not the result of abuse or misuse within the warranty period, please return by freight pre-paid and
amendment will be made without any charge. Eutech Instruments/Oakton Instruments Customer
Service Dept. will determine if the product problem is due to deviations or customer abuse. Out-ofwarranty products will be repaired on an exchange basis at cost.
10.2 Packaging / Scope of delivery
The instrument is packaged in a corrugated box with an instruction manual and the following
accessories:
Wall mount version:
• Plug, nylon, red, 2 pcs
• PG13.5, cable gland, 3 pcs
• Connectors, one each of 5 way (5.08 mm), 9 way (7.62mm), 13 way (3.5mm), 8 way (3.5mm)
10.3 Return of goods
Before returning goods for any reason whatsoever, Customer Service Dept. has to be informed in
advance. Items must be carefully packed to prevent damage during shipment, and insured against
possible damage or loss. Eutech Instruments/ Oakton Instruments will not be responsible for any
damage resulting from careless or insufficient packing.
Warning: Shipping damage as a result of inadequate packaging is the user' s/distributor’ s responsibilit y,
whoever applicable. Please follow the guidelines below before shipment.
10.4 Guidelines for returning unit for repair
Use the original packaging material if possibl e when shippi ng the unit for repair. Other wise wrap it with
bubble pack and use a corrugated box for better protection. Include a brief description of any faults
suspected for the convenience of Customer Service Dept., if possible.
10.5 Maintenance and Cleaning
Maintenance
The lpha pH 2000D contains no user repairable components. Please contact Eutech Instruments or
its distributor if there is any problem with the unit.
Cleaning
To remove dust, dirt and spots, the external surfaces of the transmitter may be wiped with a damp, lintfree cloth. A mild household cleaner can also be used if necessary
.
- 34 -
Page 40
A
11 Appendices
11.1 Appendix 1 – Unit fuse and jumper settings
Caution! Before opening the unit to replace the unit fuse, make sure the mains cable is
separated from the power supply
.
View from both PCBA side
Factory setting: NTC300
Main Rev 0.2
lpha pH/DO20000W New Main Rev 0.2part No.: 84X36820 2
Factory setting: NTC300
Fuse 250V, 315 mA,
Time Delay
- 35 -
Page 41
11.2 Appendix 2 – pH buffer values at various temperatures
The following table shows the various pH values at different temperature of the solution during
calibration.
11.3 Appendix 3 – Simple explanation on the function of hysteresis
SP1 Set to LO
SP2 Set to HI
RELAY ON
RELAY OFF
4.0
SP1
4.5
7.0
9.510.0
SP2
FORWARD DIRECTION
REVERSE DIRECTION
HYSTERESIS BAND
(DEFAULT = 0.5 pH)
The controller relay activates when the set-point is reached. In the reverse direction, it does n ot deactivate when the value reaches the set-point. Instead, it continues to be active till the value reaches
the amount set by the Hysteresis band
.
- 37 -
Page 43
2
11.4 Appendix 4 – General instructions concerning Controller Setting
11.4.1 Control characteristic of Controllers used as limit value switch
MIN functionMAX function
-Xw
Xp = 0
100%Yh
50%
0%
SP 2SP 1
Xp = 0
11.4.2 Control characteristic of P-Controllers as proportional controller
MIN functionMAX function
100%Yh
+Xw
50%
-Xw
Xp
Prop. bandP rop. band
SP 1
0%
Xp
SP
11.4.3 Control characteristic of PI-Controllers as proportional integral controller
100%
50%
25%
SP1 SP 2
20%
10%
Proportional. ba nd
X
P
Prop. band
X
P
+Xw
- 38 -
Page 44
11.4.4 Control signal of Pulse length Controllers
Relay
Pulse Length T
tON
ON
OFF
tOFF
Time [s]
The output relay of the pulse length controller is clock-timed. The switching period T remains constant.
Depending on the divergence from the limit value, the switch on time tON is increased or decreased in
accordance with the proportional range Xp.
The following applies:
tON + tOFF = T (Const.)
greater divergence Î greater tON
Xp exceeded Î tON = T (relay remains picked up)
- 39 -
Page 45
11.4.5 Control signal of Pulse Frequency Controllers
Relay
Pulse Le ngth T
tON
ON
OFF
tOFF
Time [s]
The output relay of the pulse frequency controller is clock-timed. The pulse duration tON remains
constant at 250 msec. Depending on the divergence from the limit value, the frequency (1/T) is
increased or decreased in accordance with the proportional range Xp.
The following applies:
tON = Const. (250 msec.)
greater divergence Î greater f (greater frequency)
Xp exceeded Î max. frequency
- 40 -
Page 46
11.5 Appendix 5 – Abbreviations used in menu displays
Abbreviation Meaning Abbreviation Meaning
MEAS Measurement CUR. 1 Output current 1
CAL Calibration CUR. 2 Output current 2
ENT Enter OUT Output signal
OFS Offset 4 - 20 4 to 20mA
C. CD Calibration security code 0 - 20 0 to 20 mA
S. CD Setup security code R.0 Value at 0 mA
SET Setting R. 4 Value at 4 mA
ATC Automatic temperature calibration R. 20 Value at 20 mA
SP1 Set point 1 CU22 Out of range output current 22 mA
SP2 Set point 2 WASH Wash
LO Low limit H. INT Cleaning interval in hours
HI High limit S. DUR Cleaning duration in seconds
HYS Hysteresis CNFG Configuration
ON. D On delay BKLT Back light
OFF. D Off delay LEVL Level
CNTR Controller PH SY Symmetrical pH mode
L. CT Limit control ORP SY Symmetrical ORP mode
PLC Pulse length control AL. D Alarm delay
PFC Pulse frequency control AL.C Alarm Contact
P/PI Proportional control STDY Steady
EN Energized FLET Fleet, impulse
DEEN Deenergized DEF Default
REL Relay FCT DEF Factory default
PRP Proportional band CAL DEF Calibration default
T. PL Pulse length time
F. PF Pulse frequency
IAT Integral action time
MANU Manual
- 41 -
Page 47
Page 48
Water Analysis Instruments
North America
166 Cummings Center
Beverly, MA 01915 USA
Toll Free: 1-800-225-1480
Tel: 1-978-232-6000
Dom. Fax: 1-978-232-6015
Int’l Fax: 978-232-6031