B&C CL 7685 User manual

UNI EN ISO 9001:2000
CERT. N. 9115 BCEL
B&C Electronics Srl – Via per Villanova 3 – 20040 Carnate (Mi) – Italy P.IVA 00729030965
Tel [phone] – Fax [phone] [e-mail] - www.bc-electronics.it
OPERATOR'S MANUAL
CL 7685
RESIDUAL CHLORINE
CHLORINE DIOXIDE - D. OZONE
MICROPROCESSOR CONTROLLER
* potentiostatic *
Rev. C
Valid for Option 091.3711
Range: 0/2.000/20.00 PPM
Temperature range: -2/+52 °C
Power supply: 110/220 Vac
Software: R 2.3x
Cod. 28006765

B&C Electronics CL 7685
Operator’s Manual - Rev. C - 05/05 - 2 –
Index
1 GENERAL .........................................................................................................................................4
1.1 Functional specifications ..........................................................................................................5
1.2 Physical description..................................................................................................................8
2 SPECIFICATIONS............................................................................................................................9
3 INSTALLATION ............................................................................................................................14
3.1 Physical installation................................................................................................................14
3.2 Electrical installation ..............................................................................................................14
3.3 Operating the system ..............................................................................................................17
Pre-operation check.............................................................................................................................17
4 KEYBOARD ...................................................................................................................................18
5 READOUT SEQUENCES ..............................................................................................................19
6 CALIBRATION SEQUENCES ......................................................................................................22
6.1 Operating mode selection .......................................................................................................22
6.2 Zero and Sensitivity calibration..............................................................................................22
6.3 Temperature calibration..........................................................................................................26
6.4 Set-point A/B calibration........................................................................................................27
6.5 Alarm adjustment....................................................................................................................29
6.6 Cleaning function calibration .................................................................................................30
7 CONFIGURATION.........................................................................................................................32
7.1 Keyboard locked/unlocked .....................................................................................................32
7.2 LCD Display contrast .............................................................................................................32
7.3 Access number........................................................................................................................33
7.4 Type of measuring ..................................................................................................................33
7.5 Input range..............................................................................................................................33
7.6 Auto range ..............................................................................................................................33
7.7 Software filter .........................................................................................................................33
7.8 Cell polarization voltage.........................................................................................................34
7.9 Calibration mode ....................................................................................................................34
7.10 Temperature coefficient..........................................................................................................34
7.11 Input related to analog output n°1 (Option 091.3711)............................................................34
7.12 Analog output n°1 range.........................................................................................................35
7.13 Input related to analog output n°2 (Option 091.3711)............................................................35
7.14 Analog output n°2 range.........................................................................................................36
7.15 Set-point A operating mode....................................................................................................36
7.16 Set-point A function ...............................................................................................................36
7.17 Set-point B operating mode....................................................................................................37
7.18 Set-point B function................................................................................................................37
7.19 Alarm on Set-point A .............................................................................................................37
7.20 Alarm on Set-point B..............................................................................................................38
7.21 Alarm relay contact function ..................................................................................................38
7.22 Cleaning function ...................................................................................................................38
7.23 Cleaning time (relay D ON) ...................................................................................................38

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7.24 Holding time ...........................................................................................................................39
7.25 New access number ................................................................................................................39
8 CALIBRATION...............................................................................................................................40
8.1 Electrical calibration...............................................................................................................40
8.2 Chemical calibration...............................................................................................................40
9 PREVENTIVE MAINTENANCE...................................................................................................41

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Operator’s Manual - Rev. C - 05/05 - 4 –
1GENERAL
This series of controllers with built-in microprocessor forms an advanced system of measurement and
regulation of pH - ORP - Conductivity - Dissolved Oxygen - Chlorine in industrial processes.
Compiled into these instruments is all the know-how of B&C Electronics built up over more than 20
years of experience in the field of industrial electrochemical analysis.
We have continually developed and updated these products keeping in mind the maximum
consideration for quality, reliability, completeness of functions, simplicity of handling, and also the
cost.
The computing capability and the versatility of the microprocessor are accompanied by friendly
software specially designed to make the use of the instrument, the programming of its functions,
routine checks and calibrations easily accessible even for an untrained operator.
The alpha-numeric backlit liquid crystal display helps the operator supplying him with all the
information on functioning and on operating, while the software suggests possible steps for calibration
and set-up.
The display supplies, at the same time as the measurement, an indication of present status of the output
relays and of the output current.
For a higher level of checks, the display gives an indication of the operating conditions of the
electrochemical sensors, the current status of the calibrations, set points and analog output.
The user friendly operation of the instrument saves the operator feats of memory and continual
reference to the instruction manual.
All operations are carried out using the five key pads on the front panel, for the mode selection, the
input of calibration and set point data and the setting-up. (Fig. 1)
There are no knobs or switches to manipulate in order to operate the unit. This makes the instrument
rugged and more corrosion resistant.
A non-volatile EEPROM memory assures measurement parameters are maintained in the event of a
power interruption.
The software is provided with a "watch-dog" check for correct functioning of the programs.
The electrical circuit is protected by a device which comes back into operation automatically following
an overload or a wiring error.

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1.1 FUNCTIONAL SPECIFICATIONS
Input
The instrument accepts input from potentiostatic sensor for Active Chlorine, Chlorine Dioxide and
D.Ozone measuring.
A second input is provided for 3 wires Pt100 Temperature sensors.
Temperature compensation
The unit is supplied with manual or automatic Temperature compensation and Temperature
information may be displayed on LCD.
The instrument detects the absence or malfunctioning of the Temperature sensor and automatically
switches to manual operation mode.
Measuring ranges
The unit provides an input range which may be selected from 0/1.999 or
0/19.99 PPM.
Auto ranging function may be activated for the measuring range 0/1.999 PPM.
Auto ranging allows the operator to calibrate the unit in the low range, against a high concentration of
standard solution.
Analog output
Either a 0/20 mA or 4/20 mA isolated output may be selected, provided for interface with computer or
data loggers.
A special routine allows selection of the analog output range.
If the instrument is programmed for high range, the output may be set anywhere from 0/20.00 PPM.
If low range is selected, the output may be set anywhere from 0/2.000 PPM.
Control relays
The monitor is equipped with two SPDT control relays.
These output relays may be used in a variety of ways, and the function of each relay is programmable
by operator.
Control relays can be used in one of 3 different output modes: on/off, pulse width modulation and
pulse frequency modulation.
The on/off mode of operation is used for simple control or for alarm purposes. Each control relay may
be programmed for set-point, high/low, hysteresis or dead band, delay time for actuation.
The proportional mode of operation is used for more accurate control.
Each control relay may be programmed for set-point, high/low, proportional band, Frequency or Width
modulation.
The full display indicates the current setting and the current status of each relay.

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Alarm relay
The unit contains a SPST relay designated as an alarm relay.
This relay may be used to warn of various conditions that might indicate operational problems.
The relay will activate on either high or low concentration conditions, or on failure of the control
relays to maintain proper control.
In addition this relay may be programmed for either normal or fail-safe operation.
Cleaning function
The unit contains a SPST relay designed for the auto clean cycle.
It's possible manually activate the cleaner to test its operation.
The operator can change the frequency of cleaning.
The configuration routine selects:
- auto/manual operation
- the cleaning time
- the holding time.
During cleaning and holding time:
- messages are flashing
- analog output is held constant
- set-points and alarm relays are deactivated.
Operating mode
The instrument is provided with 3 programmable modes of operation.
- Automatic operation (AUTO):
The Automatic mode is the normal operation mode of the unit.
- Measuring operation (MEAS.):
In this mode of operation the display indicates only the concentration but
the control relays are deactivated.
This would be the mode to use if the relays are not being used for alarm or control functions.
The measuring mode of operation is useful for start up or for manual operation of disinfection plants.

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- Simulated operation (SIM.):
This mode of operation would normally only be used for control system troubleshooting.
The unit does not provide the measuring values, but will allows the relays to be manually activated and
the analog output corresponding to the values on the display, to be manually selected by the operator.
The display does not indicate the measuring units (PPM) and access to calibration of the parameters is
not allowed.
The message "SIM" is shown on the display, indicating the current operation mode of the instrument.
Calibration mode
The instrument may be programmed for the immediate or postponed calibration.
The immediate calibration mode allows the operator to calibrate the unit immediately against a field
measurement on the same sample that the sensor is measuring.
The postponed calibration mode allows the operator to calibrate the unit against a laboratory
measurement on the same sample that the sensor is measuring.
The calibration may be performed later even if the sample concentration
that the sensor is measuring has changed.
Software filter
The unit is provided with a programmable software filter, to be inserted when the readout is not stable.
In order to maintain a satisfactory speed of response of the system it is suggested to insert a time value
which is equal to 1/2 or 1/4 the response time of the sensor itself.
Configuration
The electronics for the monitor is designed to be as flexible as possible.
A number of programming functions are provided in the Configuration menu and are protected by an
access number, which must be entered to allow changes in this setting.
The routine allows programming of a custom access code number.
Front panel lock
The keys on the front panel of the monitor can be used for both changing the display and for
calibrations and set-point adjustments.
When the monitor is shipped, all functions are accessible.
However, the adjustment and calibration functions may be locked in order to prevent unauthorized
adjustments to the instrument.

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Options
091.3711 Dual isolated and programmable output
The operator may select an output for Temperature.
091.404 24 VAC power supply.
091.701 RS232 isolated output
The output sends the data (PPM,°C) to the serial port of the computer.
1.2 PHYSICAL DESCRIPTION
The controller enclosure is designed for surface or panel mounting.
It consists of an anodized aluminium case built according to the standard DIN 43700, with an
aluminium panel coated with scratch-proof and non-corrosive polycarbonate membrane.
A transparent waterproof front door SZ 7601 can be added to the housing, in order to protect the unit
from excessive moisture or corrosive fumes.
Signal and power cable connections are made by using two special extractable terminal blocks
placed in the back of the instrument.
This makes wiring, installation and general maintenance of the probes and other devices easier.
The package is supplied complete with fixing clamps for panel-mounting.

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Operator’s Manual - Rev. C - 05/05 - 9 –
2SPECIFICATIONS
The DEFAULT values are correspondent to the factory calibration values.
Parameters marked by " * " can be modified in the Configuration procedures.
1) OPERATING MODE | DEFAULT
|
Automatic/Measuring/Input simulation | Auto
2) MEASURING TYPE |
|
* Chlorine/Chlorine dioxide/D. Ozone | Chlorine
3) INPUT SCALES |
|
* Input range: 2.000/20.00 PPM | 20.00
|
Display resolution at 20 °C: 1/2000 |
* Software filter 90% RT: 0.6/99.9 s |
|
Current at 20 °C: 250/5000 nA/PPM | 2000
Cell Sensitivity: 12.5/250% | 100%
Zero: +/- 2 0 µA adjustment | 0 µA
* Comp. Temp. Coefficient Cl/ClO2: 0/4.0 % / °C | 2.0% / °C
* Comp. Temp. Coefficient O3: 0/4.0 % / °C | 2.5% / °C
* Polarization Voltage: | -200 mV
4) TEMPERATURE |
|
Input: RTD Pt100 |
Connection: 2/3 wires |
Measuring and compensation range: -2/+52 °C |
Resolution: 0.1 °C |
Zero adjustment: +/- 2°C | 0 °C
Manual Temperature compensation: 0/50 °C | 20 °C

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5) SET A/B |
|
* Selectable actions: |
ON-OFF |
PFM - Pulse frequency proportional |
PWM - Pulse width proportional |
* Action: ON-OFF | SET B
Value: 0/2.000 - 0/20.00 PPM (as scale selected) | 0 PPM
Hysteresis: 0/0.200-0/2.00 PPM (as scale selected) | 0.2 PPM
Activation delay: 0/99.9 " | 0.0"
* Function: HI/LO (Max/min) | LO
|
* Action: PFM | SET A
Value: 0/20.00 PPM (as scale selected) | 0 PPM
Proportional band: 0/0.200 - 0/2.00 PPM | 0.2 PPM
(as scale selected) |
Pulse max. Frequency: 0/120 pulse/minute | 100 p/m
Pulse width: | 0.1"
* Function: HI/LO (Max/min) | LO
|
* Action: PWM |
Value: 0/0.200 - 0/20.00 PPM (as scale selected) | 0 PPM
Proportional band: 0/0.200 - 0/2.00 PPM | 0.2 PPM
(as scale selected) |
Pulse width: 0/99.9" | 20.0"
Min. pulse width: | 0.3"
* Function: HI/LO (Max/min) | LO
Relay Contacts: SPDT 220 V 5 A Resistive load |
6) ALARM (RELAY C) |
|
High value: 0/2.000 - 0/20.00 PPM (as scale selected) | 20.00 PPM
Low value: 0/2.000 - 0/20.00 PPM (as scale selected) | 0.00 PPM
Delay: 0/99.9 " | 0.0"
* Alarm on max. SA: ON/OFF | OFF
* Max. time SA: 0/60 minutes | 60 min
* Alarm on max. SB: ON/OFF | OFF
* Max. time SB: 0/60 minutes | 60 min
* Contact type: ACT/DEA | ACT
Relay Contact: SPST 220 V 5 A Resistive load |

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Operator’s Manual - Rev. C - 05/05 - 11 –
7) CLEANING FUNCTION (RELAY D) |
|
* Action: Disable/Manual Clean/Auto+Manual Clean | Disable
|
Auto Clean: |
Time repetition: 0.1/24.0 h | 24.0 h
* Cleaning time: 0.5/60.0" | 15.0"
* Hold time: 0.1'/20.0' | 3.0'
|
Relay contacts: SPST |
8) ANALOG OUTPUT Nr. 1 |
|
* Current range: 0-20/4-20 mA | 0/20 mA
* Point 1 corresponding to 0 mA or 4 mA |
RANGE 20.00 PPM: 0.00/20.00 | 0.00 PPM
RANGE 2.000 PPM: 0.000/2.000 | 0.000 PPM
TEMPERATURE: 0.0°C/50.0°C (Option 091.3711) | 0.0 °C
* Point 2 corresponding to 20 mA |
RANGE 20.00 PPM: 0.00/20.00 | 20.0 PPM
RANGE 2.000 PPM: 0.000/2.000 | 2.000 PPM
TEMPERATURE: 0.0°C/50.0°C (Option 091.3711) | 50.0 °C
Response time: 10 s for 98 % |
Isolation: 250 Vca |
Rmax: 600 Ω|
9) ANALOG OUTPUT N°2 (only for Option 091.3711) |
|
* Current range: 0-20/4-20 mA | 0/20 mA
* Point 1 corresponding to 0 mA or 4 mA |
RANGE 20.00 PPM: 0.00/20.00 | 0.00 PPM
RANGE 2.000 PPM: 0.000/2.000 | 0.000 PPM
TEMPERATURE: 0.0 °C/50.0 °C | 0.0 °C
* Point 2 corresponding to 20 mA |
RANGE 20.00 PPM: 0.00/20.00 | 20.00 PPM
RANGE 2.000 PPM: 0.000/2.000 | 2.000 PPM
TEMPERATURE: 0.0 °C/50.0 °C | 50.0 °C
Response time: 10 s for 98 % |
Isolation: 250 Vca |
Rmax: 600 Ω|

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Operator’s Manual - Rev. C - 05/05 - 12 –
10) SERIAL COMMUNICATION (Option 091.701) |
|
Baud Rate: 4800 bit/s |
Nr. of bit: 8 bit |
Nr. of stop bit: 1 bit |
Parity: None |
Isolated from measure circuits |
Example of data sent: ± 20.00 PPM ± 50.0 °C |
Data sent every: 0.4 s |
11) PARAMETERS ON CONFIG. BLOCK (See for *) |
|
Free calibration (access code not required): |
Keyboard Lock/Unlock | Unlock
LCD contrast (0/7). | 4
|
Under access code number: (0) | 0
Type of measure:Cl/ClO2/O3| Cl
Measuring range: 2.000/20.00 | 20.00 PPM
Auto ranging: On/Off | Off
Software filter response time | 15 s
Polarization | - 200 mV
Immediate/postponed calibration mode | Immed.
Temperature Coefficient | 2.0%
Input connected to the output N°1 | PPM
Analog output N°1 range (0/20 4/20 mA) | 0/20 mA
Point 1 corresponding to 0 mA or 4 mA | 0.00 PPM
Point 2 corresponding to 20 mA | 20.00 PPM
Input connected to the output N°2 | PPM
Analog output N°1 range (0/20 4/20 mA) | 0/20 mA
Point 1 corresponding to 0 mA or 4 mA | 0.00 PPM
Point 2 corresponding to 20 mA | 20.00 PPM
Action of relays A (On-Off/PFM/PWM) | PFM
Function of the A (HI/LO) | LO
Action of relays B (On-Off/PFM/PWM) | On-Off
Function of the B (HI/LO) | LO
Alarm on max. operating time of SA | Off
Max. operating time of SA for alarm | 60 m
Alarm on max. operating time of SB | Off
Max. operating time of SB for alarm | 60 m
Alarm relay status (ACT/DEA) | ACT
Cleaning function (Auto/Manual/Disabled) | Disabled
Cleaning time: 0.5/60.0" | 15.0"
Holding time: 0.1'/60.0' | 3.0'
Access number: 0/999 | 0

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12) GENERAL SPECIFICATIONS
Alphanumeric display: 1 line x 16 characters
Response time to 98% of value changing,
with TC=2% / °C - T=20 °C - S=100% :
< 5 s for HI range
< 15 s for LO range
Operating Temperature: 0/50 °C
Humidity: 95% without condensate
Power supply: 110/220 Volt ac +/- 10% 50/60 Hz
Isolation: 4000 V between primary and secondary (IEC 348)
Power: 5 VA max.
Terminal block: extractable
Weight: 850 g
Dimensions: 96 x 96 x 155 mm

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Operator’s Manual - Rev. C - 05/05 - 14 –
3INSTALLATION
3.1 PHYSICAL INSTALLATION
The controller may be installed close to the areas being monitored, or it may be located some distance
away in a control area.
The enclosure is designed for panel-mounting.
It should be mounted on a rigid surface, in a position protected from the possibility of damage,
excessive moisture and corrosive fumes.
The cable from the probe must be protected by a sheath and not installed near power cables.
Interruption on cables must be avoided or carried out by high insulation terminals.
When installing "in line" electrodes it is suggested to follow the specific instructions given by the
sensor's manufacturer.
3.2 ELECTRICAL INSTALLATION
All connections within the controller are made on detachable terminal strips located on the rear side.
(Fig. 2)
All power and output-recorder connections are made at the 13_ pin terminal strip, while input signal
connections are made at the 12_ pin terminal strip.
The electrical installation consists of:
Connecting the power
- connect ground to terminal 4
- connect ac power to 1 - 2 terminals if power voltage is 110 Vac
- connect ac power to 1 - 3 terminals if power voltage is 220 Vac
- if 091.404 option is installed, connect 24 Vac to 1-3 terminals
WARNINGS
- power the device by means of an isolation transformer
- avoid mains-voltage from an auto-transformer
- avoid mains voltage from a branch point with inductive loads
- separate power supply wires from signal ones
- control the mains voltage value

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Connecting the sensor
- Sensor cabling is a critical part of the whole system.
- Use original cable supplied with the sensor
- Avoid interruption on the cable
- connect the White wire (Counter electrode) to the terminal 17 marked EL
- connect the Black wire (Measuring electrode) to the terminal 18 marked IN
- connect the shield (Reference electrode) to the terminal 19 marked R
Connecting alarms, pumps, valves
The output connections referred to Set-point SA and Set-point SB are made at terminal strip and they
consist of two independent SPDT relays corresponding to Regulator A and Regulator B .
The output connection referred to alarm consists of SPST relay corresponding to Alarm C.
The output connection referred to auto-clean consists of SPST relay
corresponding to Auto clean D.
Control relay "A" Set-point "SA"
Terminal 6_ marked C_ : common contact
Terminal 5_ marked NO_ : normal open contact
Terminal 7_ marked NC_ : normal closed contact
Control relay "B" Set-point "SB"
Terminal 9_ marked C_ : common contact
terminal 8_ marked NO_ : normal open contact
terminal 10_ marked NC_ : normal closed contact
Alarm relay "C"
Terminal 12_ marked C_ : common contact
Terminal 11_ marked NO_ : normal open contact
Auto clean relay "D"
Terminal 12_ marked C_ : common contact
Terminal 13_ marked NO_ : normal open contact

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Operator’s Manual - Rev. C - 05/05 - 16 –
Connecting a recorder
A current output for a remote recorder or P.I.D. regulators is available on terminals 14-16.
Connect the recorder high (+) to terminal 14
Connect the recorder low (-) to terminal 16
Series connection is required for driving more loads having a total input Resistance lower than 600 Ω.
If the 091.3711 dual output option is installed, a second isolated and programmable output is available
between 15-16 terminals.
Output N°1 and Output N°2 are isolated and selectable 0/20 or 4/20 mA.
Connecting the RTD
The instrument has the automatic Temperature compensation carried out by means of RTD Pt100.
To operate the automatic Temperature compensation, connect the RTD as shown in the "connection"
figure.
A three wire connection is suggested to achieve an accurate compensation over a long distance
between the sensor and the controller.
3-wire connection
- connect the terminal of RTD to terminal 23 of the meter;
- connect the common terminal of RTD to terminals 24 - 25 of the meter;
- the 3 wire-cable must not be interrupted on the overall length.
If an extension is needed, the cable must be fastened to the high insulation terminal strip;
- keep the cable away from power wires.
The RTD connection as above described allows the controller to provide a digital readout of
Temperature.
If the Temperature sensor is not connected or damaged, the unit will operate in manual Temperature
compensation automatically.
2-wire connection
- connect the Pt100 to terminals 23 - 24 ;
- install a jumper to terminals 24 - 25.
Checking
Before connecting the system to the power supply:
- check that all cables are properly fastened to prevent strain on the connections
- check that all terminal-strip connections are mechanically and electrically sound

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3.3 OPERATING THE SYSTEM
Pre-operation check
The system's controls and indicators are all located on the front panel. (See Fig. 1).
The meter has a LCD display 1 indicating that unit is on.
The cards of the controllers are adjusted at the factory.
If sensors and probes have been connected correctly, as described in the above sections, the system
should function correctly needing only the start up and the parameters calibrations as described in the
following section.

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Operator’s Manual - Rev. C - 05/05 - 18 –
4KEYBOARD
KEY SYMBOL FUNCTION
ù [MODE]
- allows the operator to go to the next Display
- allows to go back to the main Display. The eventual
new parameter values will not be memorized
§ [CAL]
- allows the access of calibration sequences
ò [/\]
- allows to increase the displayed parameters
- allows to choose between different functions
ç [\/]
- allows to decrease the displayed parameters
- allows to choose between different functions
£ [ENT]
- allows to enter the selected data and to return to the
main Display D0

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Operator’s Manual - Rev. C - 05/05 - 19 –
5READOUT SEQUENCES
Applying the power to the instrument the display will show the input selected for approximately 3
seconds, then will show the main display DO.
_
|Cl2 meter | |ClO2 meter | |O3 meter |
Press [MODE] to visualize the following Display:
DO - actual Cl/ClO2/O3values, set-point status/functions
D1 - actual Cl/ClO2/O3values
D2 - temperature value
D3 - set-point A parameters
D4 - set-point B parameters
D5 - alarm parameters
D6 - cleaning function parameters
D7 - input/analog output N°1 values
D7BIS - input/analog output N°2 values
D8 - configuration display
D9 - instrument code and software release
D0 |0.700 ppm àA ìB| |0.700 ppm MEAS ||0.700 SIM àA ìB|
0.700PPM: actual Cl/ClO2/O3value
MEAS/SIM: mode of operation
A: set-point A state and function
ìdeactivated relay
èthe process has reached the set-point and the relay
àactivated relay
B: set-point B state and function
MESSAGE MEANINGS
" ---- " the instrument is changing the scale
" >>>> " the present value is over range
" <<<< " the present value is under range
"display flashing" the present measuring value is in alarm range or
the set-point SA or SB are in alarm (see alarm section)
" CLEAN " autoclean activated(relay D on)
" HOLD " Unit in Hold
[CAL] to activate the manual/automatic mode selection procedure

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Operator’s Manual - Rev. C - 05/05 - 20 –
[MODE] to go to
----------------------------------
_
D1 |0.700 ppm Cl2 |Cl/ClO2/O3values
[CAL] to activate the Zero/Sensitivity calibration procedure
[MODE] to go to
----------------------------------
_
D2 |TEMP.: 22.0°CM|Temperature value
M: manual value
[CAL] to activate the Temperature calibration or the manual Temperature value
selection procedures
[MODE] to go to
----------------------------------
_
D3 |SA: 0.60 * F àL| Set-point A parameters display
0.60 :set-point value
à :set-point actual state
* : Alarm on set point A activated
F : selected action (F=PFM - W=PWM - O=on/off)
L : selected function low/high (L-H)
[CAL] to activate the programming sequences for set-point A value, hysteresis and
delay time
[MODE] to go to
----------------------------------
_
D4 |SB: 0.80 * O ìH| Set-point B parameters display
0.80 : set-point value
ì : set-point actual state
* : Alarm on set point B activated
O : selected action (F=PFM - W=PWM - O=on/off)
H : selected function (L-H)
[CAL] to activate the programming sequences for set-point B value, hysteresis and
delay time