B&C Electronics OD 7685 INSTRUCTION MANUAL
CERT. N. 9115 BCEL
INSTRUCTION MANUAL
UNI EN ISO 9001:2000
OD 7685
DISSOLVED OXYGEN CONTROLLER
MICROPROCESSOR BASED
D. Oxygen scales: 0/200.0 %air
0/200.0 mmHg
0/20.00 PPM
0/20.00 mg/l
Temperature scale: -2/+52 °C
Power supply: 110/220 Vac
Software: R2.2x
Option
S/N
REP N°
Valid for options 091.3711 e 091.601
Cod. 28006762 - Rev. D - 12/06
B&C Electronics Srl - Via per Villanova 3 - 20040 Carnate (Mi) - Italy - P.IVA 00729030965
Tel +39 039 63 1721 - Fax +39 039 607 6099 – bc@bc-electronics.it - www.bc-electronics.it
B&C Electronics OD 7685
Index
1 GENERAL .........................................................................................................................................4
1.1 Measuring principle..................................................................................................................5
1.2 Measuring system .....................................................................................................................5
1.3 Functional specifications ..........................................................................................................6
1.4 Physical specifications..............................................................................................................9
2 SPECIFICATIONS..........................................................................................................................10
3 INSTALLATION ............................................................................................................................14
3.1 Controller installation .............................................................................................................14
3.2 Sensor installation...................................................................................................................14
3.3 Electrical connections.............................................................................................................15
3.4 Operating the system ..............................................................................................................18
4 KEYBOARD ...................................................................................................................................20
5 READOUT SEQUENCES ..............................................................................................................21
6 CALIBRATION SEQUENCES ......................................................................................................27
6.1 Manual/automatic mode .........................................................................................................27
6.2 Zero and Sensitivity calibration..............................................................................................28
6.3 Secondary parameters calibration...........................................................................................34
6.4 Set-point A/B setting ..............................................................................................................37
6.5 Alarm setting ..........................................................................................................................39
6.6 Cleaning function ...................................................................................................................40
7 CONFIGURATION.........................................................................................................................43
7.1 Keyboard locked/unlocked .....................................................................................................43
7.2 LCD display contrast ..............................................................................................................43
7.3 Access number........................................................................................................................44
7.4 Cell type..................................................................................................................................44
7.5 Microtransmitter selection......................................................................................................45
7.6 Measuring unit........................................................................................................................45
7.7 Thermocompensation type......................................................................................................45
7.8 Thermocompensation coefficient ...........................................................................................45
7.9 Calibration mode ....................................................................................................................46
7.10 Polarization voltage ................................................................................................................46
7.11 Software filter .........................................................................................................................46
7.12 Input relared to analog output n°1 (Option 091.3711) ...........................................................47
7.13 Analog output n°1 range.........................................................................................................47
7.14 Input related to analog output n°2 (Option 091.3711)............................................................47
7.15 Analog output n°2 range.........................................................................................................48
7.16 Set-point A function ...............................................................................................................48
7.17 Set-point B function................................................................................................................48
7.18 Alarm on set-point A ..............................................................................................................49
7.19 Alarm on set-point B ..............................................................................................................49
7.20 Alarm relay C contacts ...........................................................................................................50
7.21 Cleaning function ...................................................................................................................50
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7.22 Cleaning time (Relay d on).....................................................................................................50
7.23 Holding time ...........................................................................................................................50
7.24 New access number ................................................................................................................51
8 CALIBRATION...............................................................................................................................52
9 PREVENTIVE MANTENIANCE...................................................................................................54
10 TROUBLESHOOTING...................................................................................................................55
11 APPENDIX Nr. 1 (Valid for option 091.601) .................................................................................59
WARRANTY CERTIFICATE...............................................................................................................62
REPAIRS................................................................................................................................................62
TECHNICAL SUPPORT .......................................................................................................................63
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B&C Electronics OD 7685
1 GENERAL
The instrument structure has been designed considering the three way of use:
1) The user checks measuring values and the proper functioning of the instrument.
The user should consult the Chapters 1 and 2.
2) The user should define the operating parameters and carry out the periodic calibration.
The user can carry out the following choices and operations:
- operating with keyboard locked/unlocked
- manual/automatic operating mode
- selecting the values of Set-point, Hysteresis, and Delay time for the relay switching
- selecting the Minimum/maximum function and the alarm Delay time
- calibrations
- programming the Cleaning function
3) The user should operate the functioning choice required for the system in which the instrument is
used.
After the installation the instrument should be configured for the desired functioning.
Can be carried out:
- selections between possible options
- input numeric values within a fixed range
We suggest to follow the next steps:
1) in the Chapter 2 "Specifications", locate parameters marked with
"*" and the corresponding factory values in the "Default" column
2) make a list of changing in order to fit with the specific application
3) insert the "Configuration" access code to:
** select the Dissolved Oxygen sensor type
** select the measuring unit
- program the two Software Filter response time
- select the calibration mode
- program the Automatic Pressure Compensation (option)
- select the input for the analog output N°1 and N°2
- select the mA output range
- program the measuring value corresponding to 0/4 and 20 mA
** select the Min/Max function for the Set-Point A and B
- program the alarm action on the activation time for Set-point A and B
- program the Max. activation time for Set-point A and B
- select the Activated/Deactivated function for relay C
- program the Cleaning function (relay D)
- select the Access number to the Configuration
(The choice of the parameters marked ** is the minimum required for the use of the instrument).
Refer to the Chapter 7 "Configuration".
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B&C Electronics OD 7685
1.1 MEASURING PRINCIPLE
Polarographic method
The measurement is performed with a Polarographic sensor introduced by Clark and still represents
the more practical measuring system since it allows accurate and fast measurement as well as easy
calibration procedures.
The method consists of the Dissolved Oxygen diffusion through a membrane which divides the
sample from an electrolytic cell with a Silver Anode and a Platinum Cathode.
A suitable polarization Voltage generates a current flow which is proportional to the diffused
Dissolved Oxygen through the membrane.
The Oxygen in the cell will be restored by the continuous diffusion through the membrane. The result
is a great stability of the measurement.
Anyway the method is influenced by two physical factors: the Temperature and the sample speed.
Temperature effect
The membrane is affected by a contraction/dilatation at the Temperature variation, with the
consequence of a variation of the membrane porosity.
This changing modify the diffusion speed of the Dissolved Oxygen through the membrane and
consequently a different measuring.
This effect is compensated by the instrument by means of a Thermoresistance included in the
D.O. sensor.
Sample speed effect
The Oxygen diffusion through the membrane will decrease the concentration close to the membrane,
resulting in a reduction of the measuring value.
For this reason it is necessary to allow a continuous flow of the sample with a speed from 0,3 to 0,7
meter/second close to the membrane.
Avoid air bubbles in the sample that would affect the measuring accuracy.
1.2 MEASURING SYSTEM
The Dissolved Oxygen monitoring system consists of two parts:
- the measuring/regulating instrument which is discussed in this instruction manual
- the Dissolved Oxygen sensor
The system could be implemented with additional devices for field application:
B&C Electronics amplified sensor, Temperature sensor, recorder, remote display, ON-OFF regulators,
PID regulators, sensor Cleaning devices.
Instrument
This instrument carries out the following functions:
1) Dissolved Oxygen measuring when connected to the sensor
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2) manual or automatic Dissolved Oxygen regulation, if suitable devices are connected to the output
relays
3) Temperature measuring, if an RTD Pt100 is connected
4) manual or automatic compensation of Temperature, Pressure, Salinity and Relative Humidity
effects
5) alarm devices activation when unexpected measuring and Set-point conditions happen
6) D.O. and/or Temperature acquisition, when connected to a Recorder or a Data Logger
7) sending data via a Serial interface, if the option 091.701 "RS232" is installed
8) external device activation for the sensor Cleaning
9) Barometric Pressure measuring if the option 091.601 is installed
Sensor
For the proper functioning of the system it is necessary to use the suitable sensor for each specific
application.
The sensor installation should allow a continuous contact with the sample, in a position with sufficient
stirring and exchange of sample.
In some applications the use of sensor Cleaning devices is suggested.
1.3 FUNCTIONAL SPECIFICATIONS
R2.2x Software specification updates
- Two Software Filter Time depending on the amplitude of the input signal changing
- Selectable access number to the Configuration
- Manual Temperature calibration even with sensor connected
- Sensor cleaning function
- Barometric Pressure reading (option)
- Sensor calibration in Immediate/Postponed mode
- Type of sensor and microtransmitter selection.
Input
The instrument accepts input from three sensors:
- Dissolved Oxygen sensor;
- Temperature sensor (Pt100);
- Barometric Pressure internal sensor (option).
Software Filter
The unit is provided with a programmable software filter, to be inserted when the readout is not stable.
The user may select different filter values for small and large signal fluctuations.
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D.Oxygen sensor type
The following sensor type can be used:
- 3 polarographic sensor types with different Current in air;
- galvanic sensor;
- B&C Electronics amplified sensor (ST series)
An exclusive feature of the instrument allows to connect ST series sensors, amplified by the 080610.2
microtransmitter, for long distance applications.
Scales
The following D.O. measuring scales can be selected:
mmHg (partial pressure) - % (air saturation) - PPM - mg/litre.
The instrument holds the calibration data when changing the measuring scale.
Temperature compensation
The unit is supplied with manual or automatic Temperature compensation. The instrument detects of
the absence or malfunctioning of the Temperature sensor and automatically switches to manual
compensation.
Secondary parameters
The D.O. measuring is affected from Barometric Pressure, Salinity and Relative Humidity.
The programming of these parameters values avoids the use of the conversion tables.
As an option the automatic Barometric Pressure compensation can be implemented.
Analog output
Either a 0/20 mA or 4/20 mA programmable and isolated output may be selected, for use as an
interface with computers or data loggers.
The input range corresponding to the output is programmable.
Control relays
The monitor is equipped with two SPST control relays.
Each control relay may be programmed for set-point, high/low, hysteresis or delay time actuation.
The full display indicates the current settings and current status of each relay.
Alarm relay
The unit contains a third SPDT relay designated as an alarm relay.
This relay may be used to warn of conditions that may indicate operational problems.
The relay will activate on either high/low value 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.
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Operating mode
The instrument is provided with 2 programmable modes of operation.
- Automatic operation:
The Automatic mode is the normal operation mode of the unit.
- Manual operation:
This mode of operation would normally be used for control system troubleshooting.
The unit will allow the relays to be manually actuated by pushing up/down keys.
The letter "M" flashing on the display, indicates the instrument is in manual operation mode.
Calibration
The sensitivity calibration in air can be automatically performed.
The manual calibration mode can be selected in two ways:
- immediate calibration;
the user immediately adjusts the measuring value;
- postponed calibration;
the instrument memorizes the sample value;
the user adjusts the memorized value after the laboratory analysis.
Cleaning function
The unit contains a SPST relay designated as an autoclean relay.
This relay may be used to start a manual or automatic autoclean cycle.
The user may select:
- the cleaning time
- the waiting time to turn to the normal operation
- the repetition time of the cycle
During the cleaning and waiting the unit will provide:
- flashing messages
- analog outputs in hold
- control and alarm relays deactivated
Configuration
A number of programming functions are provided in the Configuration menu and are protected by a
selectable access number, which must be entered to allow changes in this setting.
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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IMPORTANT NOTE: the factory configuration allows the immediate use of the instrument in main
applications.
Options
091.3711 Dual isolated and programmable output.
Two outputs may be configured for Concentration or Temperature.
091.701 RS232 isolated output.
The output sends the data (Concentration, °C) to the serial port of the computer.
091.404 24 VAC power supply.
091.4143 9/36 VDC power supply.
1.4 PHYSICAL SPECIFICATIONS
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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B&C Electronics OD 7685
2 SPECIFICATIONS
The Default values are corresponding to the factory calibration values.
Parameters marked by " * " can be modified in the Configuration procedures.
Default
OPERATING MODE
Automatic/Manual Auto
SENSOR TYPE
* 250nA-P/45nA-P/300nA-P/30mV-G 250nA-P
* Microtransmitter: On/Off Off
Input from POLAROGRAPHIC CELL 250
Current in air input at 20°C: 200/400 nA 250 nA
* Thermocompensation: according to internal table/Coefficient Table
* TC selectable: 0/4 %/°C 2.3%
(table arranged for SZ654.1 cell with Vpol. 675 mV)
Input from POLAROGRAPHIC CELL 45 nA
Current in air input at 20°C: 25/75 nA 45 nA
* Thermocompensation: according to internal table/Coefficient Table
* TC selectable: 0/4 %/°C 2.3%
Input from POLAROGRAPHIC CELL 300 nA
Current in air input at 20°C: 170/510 nA 300 nA
* Thermocompensation: according to internal table/Coefficient Table
* TC selectable: 0/4 %/°C 2.3%
Polarization voltage: 0/1250 mV 675 mV
Input from GALVANIC CELL 30 mV
Voltage in air input at 20°C: 17/51 mV 30 mV
* Thermocompensation: according to internal table/Coefficient Table
* TC selectable: 0/4 %/°C 2.3%
Software filter 90% RT:
* Large signal variation: 0.4/20.0 sec. 2.0 sec
* Small signal variation: 0.4/20.0 sec. 10.0 sec
Ref. Temp. for the Thermocompensation: 20°C
* Scales: % air saturation: 0/200.0 % air % air sat
PPM: 0/20.00 PPM
mg/l: 0/20.00 mg/l
Partial pressure O2: 0/200.0 mmHg
Zero regulation: (+/- 3.00 nA/30 nA) +/- 10% air/20°C 0 nA
Sensitivity regulation: 55/170 % 100 %
Display accuracy at 20°C: 1/1000
Automatic calibration (function of Temp-Press-RH)
Manual calibration (function of the adjusted value)
Signalling of the calibration value stability reached
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B&C Electronics OD 7685
SECONDARY PARAMETERS
Pressure: 500/800 mmHg 760 mmHg
Salinity (Chloride): 0/60000 PPM 0 PPM
Relative Humidity: 0/100 % 50 %
TEMPERATURE
Input: RTD Pt100
Connections: 2/3 wires
Measuring and compensation range: -2/+52 °C
Accuracy: 0.1 °C
Zero adjustment: +/- 2°C 0°C
Manual temperature value range: 0/50°C 20°C
SET-POINT A/B
Set value (function of the scale): 0/200.0 % 0 %
Hysteresis (function of the scale): 0/20.0 % 0 %
Delay time: 0.0/99.9 sec 0 sec
* Function: HI/LO (Max/Min) LO
Relay contact: SPDT 220V 5Amp resistive
ALARM (CONTACT C-D)
Low value (function of the scale): 0/200.0 % 0.0 %
High value (function of the scale): 0/200.0 % 200.0 %
Delay time: 0.0/99.9 sec 0 sec
* Alarm for max. activation time on SA (Set-point A): ON/OFF OFF
* Max. activation time for SA: 0/60 minutes 60 min.
* Alarm for max. activation time on SB (Set-point B): ON/OFF OFF
* Max. activation time for SB: 0/60 minutes 60 min.
* Contact type (activated/deactivated): ACT/DEA ACT
Relay contact: SPST 220V 5Amp resistive
CLEANING (Relay D)
* Action: Disabled/Manual Clean/Auto+Manual Clean Disabled
Auto Clean:
Repetition time: 0.1/24.0h 24.0h
* Cleaning time: 0.5/60.0" 15.0"
* Hold time (hold of analog output,
deactivation of Set-point A and B and Alarm C): 0.1'/20.0' 3.0'
Relay contact: SPST (N.O.)
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B&C Electronics OD 7685
ANALOG OUTPUT N°1
* Input related to analog output
(only for option 091.3711): PPM/°C PPM
* Output range: 0-20/4-20 mA 0/20 mA
* Point 1 (corresponding to 0 mA or 4 mA): 0.0%
mmHg/%air: 0.0/200.0
PPM/mg/l: 0.00/20.00
* Point 2 (corresponding to 20 mA): 200.0%
mmHg/%air: 0.0/200.0
PPM/mg/l. 0.00/20.00
Response time: 2.5 sec approx. for 98 %
Isolation: 250 Vca
Rmax: 600 ohm
ANALOG OUTPUT N°2 (only for Option 091.3711) Default
* Input related to analog output: PPM/°C PPM
* Output range: 0-20/4-20 mA 0/20 mA
* Point 1 (corresponding to 0 mA or 4 mA): 0.0%
mmHg/%air: 0.0/200.0
PPM/mg/l: 0.00/20.00
* Point 2 (corresponding to 20 mA): 200.0%
mmHg/%air: 0.0/200.0
PPM/mg/l. 0.00/20.00
Response time: 2.5 sec approx. for 98 %
Isolation: 250 Vca
Rmax: 600 ohm
CONFIGURATION (*) Default
Free calibration (Access number not required):
keyboard locked/Unlocked Unlocked
LCD Display contrast (0/7) 4
Access number required:
Sensor type 250nA-P
Microtransmitter: On/Off Off
D.O. input scales: mmHg/%air/PPM /mg/l % air
Thermocompensation type: Table/Coefficient Table
Thermocompensation coefficient 2,3 %/°C
Calibration mode Immediate
Polarization voltage of the cell 675 mV
RT Large software filter 2.0 sec
RT Small software filter 10.0 sec
Input related to analog output N°1 (Option 091.3711) % air
Analog output N°1 range 0/20 mA
Point 1 (x mA minimum) 0.0
Point 2 (x mA maximum) 200.0
Input related to analog output N°2 (Option 091.3711) % air
Analog output N°2 range (Option 091.3711) 0/20 mA
Point 1 (x mA minimum) (Option 091.3711) 0.0
Point 2 (x mA maximum) (Option 091.3711) 200.0
Relay A function LO
Relay B function LO
Alarm for max. activation time on SA OFF
Max. activation time for SA 60 m
Alarm for max. activation time on SB OFF
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B&C Electronics OD 7685
Max. activation time for SB 60 m
Alarm relay contact function ACT
Cleaning function Disabled
Cleaning time 15.0 sec
Hold time 3.0 min
Configuration access code number: 0/999 0
GENERAL SPECIFICATION
Alphanumeric display: 1 line x 16 character
Acquisition time: 0,1"
Updating time for main measure: 0,4"
Operating Temperature: 0/50 °C
Ambient Humidity: 95% without condensation
Power supply: 110/220 Vac +/- 10% 50/60 Hz
Isolation: 4000 volt between primary and secondary (IEC 348)
Power consumption: 5 VA max.
Terminal boards: extractable
Net weight: 850 gr.
Housing: DIN 43700 96 x 96
Dimension: 96 x 96 x 155 mm.
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B&C Electronics OD 7685
3 INSTALLATION
Packing list
The instrument packaging contain:
- N° 1 instrument with serial number label
- N° 2 brackets for panel mounting
- N° 1 English instruction manual according to IEC N° 278 standard
- N° 1 warranty certificate with Technical Assistance card, included in the instruction manual.
Unpackagin of the instrument
1) Remove from the packaging the instruction manual containing the warranty certificate.
2) Open the packaging and remove the instrument enclosed in a plastic transparent bag.
3) Remove the transparent bag preserving the two brackets.
Storage
For long storage periods hold the instrument in a dry place.
3.1 CONTROLLER INSTALLATION
The instrument can be installed near the sensor or in a distant area, in the electrical cabinet.
The panel mounting should be made in a unbending surface, in a position protected from humidity,
corrosive fumes and casual collisions.
The picture 3 shows the instrument dimensions and the panel cut-out dimensions.
- Introduce the instrument in the cut panel.
- Mount the two fastening brackets on the two sides of the instrument, with the screw head
turned to the back of the instrument.
- Screw on the two fastening brackets until a complete blockage of the housing.
In the field mounting application, the use of a protection cabinet will assure a long time reliability; it is
also available a transparent cover with IP55 protection level (mod. SZ7601).
3.2 SENSOR INSTALLATION
See the instruction manual of the sensor.
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3.3 ELECTRICAL CONNECTIONS
Safety rules
Before connecting the power supply to the instrument perform the followings check:
- check that the terminal 4 is connected to ground and that all connection are all correct
- check that the connection wires are well fastened to the terminal block
WARNING
The failure coming from erroneous connections is not covered by warranty
Refer to the back panel printing described in Figure 2.
All the connections are made with extractable terminal blocks on the back panel.
The power connections are on the lower terminal block (13 positions).
The input and output signals are on the upper terminal block (12 positions).
Connecting the power
- terminal 4 connect to the ground
- terminals 1-2 connect to the ac power (if power is 110 V)
- terminals 1-3 connect to the ac power (if power is 220 V)
(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 heavy inductive loads
- separate power supply wires from signal ones
- control the mains voltage value
- an internal device protects the unit against power overloads.
Disconnect the power and wait few minutes before powering again.
Connecting the Cell or Microtransmitter
- Use original cables suggested by the sensor manufacturer.
- Avoid interruption on the cable if a high insulation terminal block is not available.
Keep the cable away from power wires on the overall length.
Polarographic cell
- terminal 20_ connect to the cathode (Platinum electrode)
- terminal 19_ connect to the anode (Silver electrode)
- terminals 21-22_ install a jumper
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Galvanic cell
- terminal 22_ connect to the cathode (Platinum or Silver electrode)
- terminal 21_ connect to the anode (Lead electrode)
- terminals 21-22_ remove the jumper
Sensor with microtransmitter
Refer to operating instruction of this special sensor.
Connecting the RTD
The Temperature readout and the automatic Temperature compensation is provided by connecting the
Pt100.
If the Temperature sensor is not connected or damaged, the unit will operate in manual Temperature
compensation automatically.
3-wire connection
- terminal 23 connect to the Pt100
- terminals 24 - 25 connect to the Pt100 common
2-wire connection
- terminals 23 - 24 connect to the Pt100
- terminals 24 - 25 install a jumper between terminals
Connecting a recorder
Connect to terminals 14-16 for the 1st channel output
Connect to terminals 15-16 for the 2nd channel output (091.3711 option)
- terminal 14 connect to the terminal (+) of the recorder N°1
- terminal 15 connect to the terminal (+) of the recorder N°2
- terminal 16 connect to the terminal (-) of the two recorder
Series connection is required for driving more loads having a total input Resistance lower than 600
ohm for each channel.
Connecting alarms, pumps, valves
Regulators output are available on the instrument terminal block by means of relay contacts relating to
set-point A and B.
RELAY "A" SET-POINT "SA"
terminal 6 marked C common contact
terminal 5 marked NO normally open contact
terminal 7 marked NC normally closed contact
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B&C Electronics OD 7685
RELAY "B" SET-POINT "SB"
terminal 9 marked C common contact
terminal 8 marked NO normally open contact
terminal 10 marked NC normally closed contact
RELAY "C" ALARM
terminal 12 marked C common contact
terminal 11 marked NO normally open contact
Arc suppressor
Install a suitable snubber between relay terminals if the relay activation causes interferences on the
display. (B&C Electronics snubber SX101)
Connecting cleaning system
To activate the external cleaning device, use the following relay contacts.
RELAY "D" SENSOR CLEANING
terminal 12 marked C common contact
terminal 13 marked NO normally open contact
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3.4 OPERATING THE SYSTEM
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
- check that power voltage is correct
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 the unit is on.
The cards of the controllers are adjusted at the factory.
If sensors 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.
Quick start guide
The unit may be installed for the following purposes:
- measuring
- measuring and regulation
- measuring, regulation and recording
The instrument is shipped with factory calibration and configuration suitable for the most popular
applications.
For this reason the operation may require just the following steps:
measuring
1. Connect the cell to the meter.
2. Power the instrument.
The instrument will show the Display (D0).
3. The instrument is pre-configured for polarographic cell SZ654.1.
Access the Configuration menu to select other cell types.
From Display (D0) press 9 times ù to start the Configuration sequences
Eventually select the secondary parameters.
4. The instrument is pre-arranged for automatic calibration.
Perform the Dissolved Oxygen calibration in air.
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measuring and regulation
Add the following to the preceding operations:
1. Press § ò £ to go to the manual operation. If the automatic mode is selected,
go to the step 2.
2. A and B relay are configured as LOW (Minimum).
Select HIGH (Maximum) if necessary.
3. Select the Set-point, the Hysteresis and the Delay of A and B relay. From (D0) press 4 times
ù to start the Set-point A selection sequence.
From (D0) press 5 times
4. The alarm on the activation time of A and B relay is deactivated.
Activate this kind of alarm if necessary.
5. Select alarm values of min/max and delay if necessary.
From (D0) press 6 times
measuring, regulation and recording
Add the following to the preceding operations:
1. Analog output is configured as PPM at 0/20 mA corresponding to the input scale.
Select 4/20 mA and a suitable input span if necessary.
2. If option 091.3711 is installed, follow the step 1. for the second output.
This option allows to select the analog output as °C scale.
Manual operation
When the instrument is programmed for the manual operation (see Calibration sequences) the flashing
"M" will appear on the display.
Analog outputs and alarm relay will remain activated.
ù to start the Set-point B selection sequence.
ù to start the alarm selection sequence.
ò while pressing the key, A relay will be activated.
ç while pressing the key, B relay will be activated.
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4 KEYBOARD
KEY FUNCTION
ù
- it allows the operator to go to the next Display
- it allows to go back to the main Display.
The eventual new parameter values will not be memorized
- it allows the access of calibration sequences
§
- it allows to increase the displayed parameters
- it allows to choose between different functions
ò
- it allows to decrease the displayed parameters
- it allows to choose between different functions
ç
- it allows to enter the selected data and to return to the main Display D0
£
Instruction Manual - Rev. D - 12/06
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