Wallace & Tiernan GmbH
D-89305 Günzburg
Telefon (08221) 904-0
Telefax (08221) 904-203
e-mail: wtger@chemfeed.org
www.wallace-tiernan.de
DEPOLOX 4
®
MICROPROCESSOR BASED
ANALYSING AND CONTROL
SYSTEM FOR CHLORINE,
pH AND REDOX IN POTABLE
WATER AND SWIMMING POOLS
BA - 40 004 E
SALES ORDER NO. VA .............
NOTE:
The equipment has been made of first-class material and should perform satisfactorily
if properly operated and maintained. It is therefore most important that the instructions
be read, and understood, prior to installation, operation or maintenance.
Our guarantee is conditional upon the equipment being treated in accordance with this
instruction. To avoid errors please refer to the order number when corresponding with
us.
Not parts may be disassembled during the guarantee time without our permission.
At significant disturbances we recommend to call for our trained service personnel.
2
GUARANTEE
For a period of one year after shipment, we undertake to repair or replace free of
charge, f.o.b. Günzburg, all equipment or parts of our supply that have failed due to
defects in workmanship or material, provided that these parts have been used under
normal operating conditions.
Replaced parts shall become our property.
For parts not manufactured by us, especially electrical parts, our liability shall be limited
to the guarantee granted by our vendor. On the buyer’s request we will cede the
vendor’s guarantee to the buyer who shall then be solely responsible for the
implementation of the vendor’s guarantee.
Defects caused by normal wear, faulty operation, negligence or unsuitable process
materials, are excluded from our guarantee.
Also excluded are defects caused by unauthorised modifications or repairs performed
by the buyer or a third party.
The guarantee period will not be extended or renewed after a modification of the
equipment or the replacement of parts.
Defects not caused by our fault, for instance defects caused by faulty operation, use
of unsuitable chemicals or disobedience of the instruction manual, will be corrected by
us on the buyer’s request, at current prices and service charges.
Place of jurisdiction for all law suits regarding our supply or other legal matters shall
be the county court (Amtsgericht) of Günzburg or the district court (Landgericht) of
Memmingen, regardless of the extent of the claim.
3
CONTENTS
PAGE
1.
GENERAL
8
2.
DISINFECTANTS IN WATER - LIMIT VALUES
8
2.1
2.2.
2.3
Chlorine (Cl2)
Chlorine dioxide (ClO2)
Ozone (O3)
8
9
9
3.
DEPOLOX 4 - INSTALLATION AND THEORY
OF OPERATION
9
3.2
3.3
Installation of a complete chlorine residual analyser
DEPOLOX 4
Theory of operation
Temperature compensation
9-10
11
12
4.
INSTALLATION
4.1
4.2
4.3
Location of installation
Sample water take-off
Sample water drainage
12
12-13
13
14
5.
STARTUP
14
5.1
5.2
5.3
Depolox 4 analyzer (pressureless type)
Depolox 4 analyzer (pressure type max. 1.5 bar)
Amplifier for chlorine measuring cell DEPOLOX 4
14
15
15-16
6.
CALIBRATION OF THE DEPOLOX 4 AMPLIFIER
17
6.1
6.2
6.3
6.4
6.5
17
17
18
18
18
6.6
6.7
Calibration of range
Calibration of bias voltage
Zero calibration
Zero calibration with chlorine-free water
Zero calibration in case of a combination of
chlorine and ozone
Measured value calibration
Chemical analysing methods
7.
MAINTENANCE
20
7.1
7.2
7.3
7.4
7.5
7.6
7.7
Zero point and measured value check
Servicing of the reference electrode
Change of grit
Strainer
Electrodes
Chemical and mechanical cleaning
Spares for maintenance
20
20
20
21
21
21
21
3.1
19
19
edition 06/1994
4
PAGE
8.
TROUBLESHOOTING
22
9.
pH-VALUE ANALYSER
23
9.1
9.2
9.3
9.4
9.5
pH probe with special cable
Startup of ph-value analyser
Maintenance of ph probe
pH-measurement using the phenol red method
Spare parts and chemicals for maintenance
23
23-24
25
25
26
10.
REDOX ANALYSER
27
10.1
10.2
10.3
10.4
Redox probe with special cable
Start-Up
Maintenance of the redox probe
Spare parts and chemicals for maintenance
27
27-28
28
29
11.
AMPLIFIER
30
11.1
11.1.1
Installation
Dimensions of basic unit, plug-in amplifiers
and COM interface card
Electrical installation
Front panel
Keypad
Parameter and function menus - set-up and
changing of settings
Basic amplifier setup
30
31
11.2
11.3
11.4
11.5
11.6
32
33
34
34
35
12.
CHLORINE MEASURING AMPLIFIER
36
12.1
12.2
12.3
12.3.1
12.3.2
Paramter menus (standard Cl2 amplifier)
Function menus (Cl2 amplifier)
Paramter set-up during initial operation
Control element electric positioner or regulating valve
Control element metering pump, solenoid pump,
continuous output
Adjustment of feedback display
Potentiometer feedback (standard factory setting)
mA feedback
Adjustment of the feedback display
36-37
38
38
39
12.4
12.4.1
12.4.2
12.4.3
5
40
41
41
41
42
PAGE
13.
pH MEASUREMENT AMPLIFIER
43
13.1
13.2
13.3
Parameter menu (standard pH amplifier)
Function menu (pH amplifier)
Set-up of control parameters for initial operation
(parameter menu)
For metering pumps (pulse duration or
continuous controller)
For solenoid pumps (pulse frequency controller)
For electric positioners and regulation values
(step rate controller)
43-44
45
46
14.
REDOX MEASUREMENT AMPLIFIER
47
14.1
14.2
Parameter menu (standard Redox amplifier)
Function menu (Redox amplifier)
47-48
49
15.
ERROR MESSAGES
50-52
16.
INTEGRATED CONTROLLER (OPTION)
53
16.1
16.2
16.3
16.4
16.5
Three-step controller for servomotor
Metering pump controller (pulse duration controller)
Solenoid pump controller (pulse frequency controller)
Controller with continuous output
Control parameters and their influence on the control loop
53
54
55-56
57
58-61
13.3.1
13.3.2
13.3.3
46
46
46
17.
ADAPTATION OF THE CHLORINE AMPLIFIER
62
17.1
17.2
17.3
17.4
17.5
17.5.1
17.5.2
17.6
Use of the adaptation
Preconditions for the adaptation
Adaptation menus
Sequence of the adaptation
Ending the adaptation sequence
Ending of the adaptation without error
Ending of the adaptation with error
Determination of the controller parameters using Tu and Ts
62
63
63
64
65
65
66
67
18.
COM INTERFACE CARD
68
19.
SERVICING AND REPAIR
68
20.
TECHNICAL DATA
20.1
20.2
20.3
20.4
20.5
DEPOLOX 4 measuring cell
Basic unit for wall mounting
Chlorine residual amplifier
pH measuring amplifier
Redox measuring amplifier
69
69
69
70
71
72
6
PAGE
21.
DRAWINGS AND WIRING DIAGRAMS
-
-
-
BZ-1150/1-4/E
Residual analyser DEPOLOX 4 Abb. 2, Abb. 2A-E
BZ-1150/5-5/E
Residual analyser DEPOLOX 4 pressurised cell Abb. 2F
BZ-1150
Cellule de measure DEPOLOX 4 with bill of Material
BZ-1141/E
Flow regulator, complete with bill of material
BZ-1179/E
Sample water take off unit for DEPOLOX 4 with bill of material
BZ-1165/E
DEPOLOX 4 sample water arrangement
BZ-1166/E
Sample water arrangement incorporating sample water pump
with bill of material
BZ-1167/E
Sample water arrangement incorporating sample water pump
with bill of material
BZ-1184
Housing complete / U-93 743 with bill of material
30-E-7585 (sheet 1 - sheet 7)
Typical wiring diagrams for Cl2 module
30-E-7578 sheet 1
Wiring diagram - amplifier for panel mounting
30-E-7578 sheet 2
Connection COM card
U-95 590
Wall housing with bill of material
U-95 649
Panel mounting housing with bill of material
U-95 820
Panel mounting housing with bill of material
U-95 822
Panel mounting housing with bill of material
BZ-1145
Label to the amplifier
Impendance converter BZ-1222-E and BZ-1223-E
BZ-1245-E
Table of amplifiers
WN-343
Connection parts for PVC-hose
7
1.
GENERAL
The disinfection of potable water, swimming pool water and industrial water is usually
achieved by the addition of either chlorine, chlorine dioxide, sodium hypochlorite,
anorganic chlorine compounds or in combination with ozone.
It is very important to dose these disinfectants properly in order to achieve the correct
residual. An insufficient residual of the disinfectant may result in poor disinfection,
whereas an excessive residual may affect the taste of the water unfavourably or cause
corrosion in the water lines.
The DEPOLOX 4 residual analyser may be used for the continuous measurement of
disinfectant residuals such as chlorine, chlorine dioxide or ozone.
With additional equipment the dosage of these disinfectants may be controlled and
recorded.
The unit may also be used to check water which must not contain any disinfectants
(e.g. to check that no ozone is present after the water has passed through a
dechlorination filter).
2.
DISINFECTANTS IN WATER - LIMIT VALUES
2.1
CHLORINE (Cl2)
According to current German regulations, potable water must not contain more than
0.3mg/l of effective chlorine. This amount may be increased temporarily up to 0.6mg/l
if required for sufficient disinfection.
A further requirement is that potable water (and water used by the food processing
industry) disinfected with chlorine shall contain at least 0.1 mg/l of free chlorine after
chlorination.
Processed swimming pool water (after flocculation, filtering and chlorination) is required
to contain 0.3...0.6 mg/l of free chlorine in every part of the swimming pool. The water
leaving the pool shall contain at least 0.3 mg/l of free and effective chlorine. If a
treatment with ozone is included in the process, the content of free chlorine in the water
shall be 0.2...0.5 mg/l.
NOTE!
The presence of chlorisocyanurates (chlorine stabilisers) will strongly impair the
measurement of chlorine residual. These chemicals, available in the form of
granules or pills, are not approved for use in swimming pool water and must not
be used in chlorine residual controlled systems.
8
2.2
CHLORINE DIOXIDE (ClO2)
Drinking water disinfected with chlorine dioxide is required to contain at least 0.05mg/l
of chlorine dioxide after treatment.
2.3
OZONE (O3)
The ozone residual in water depends on the type of process used and should therefore be determined during operation. To remove ozone completely from water, the water
can be passed through an activated carbon filter. Potable water must not contain any
ozone.
Swimming pool water is required to contain less than 0.05 mg/l of ozone before entering
the pool.
3.
DEPOLOX 4 - INSTALLATION AND THEORY OF OPERATION
3.1
INSTALLATION OF A COMPLETE CHLORINE RESIDUAL
ANALYSER DEPOLOX 4 (see page 10)
Sample water flows through the take-off pipe (1), the shut-off valve (2), the pressure
reducing valve with strainer and gauge (3), the sample water line (4) and the flow
regulator with check valve (9) into the chlorine measuring system (8). The flow regulator
(9) is factory-adjusted and maintains a constant sample water flow through the measuring
cell. If the measuring cell is of the pressureless type, the sample water flows via the
drain line (6) into the drain funnel (5).
For additional measurement of pH and Redox, the appropriate electrodes can be plugged
into the body of the measuring cell. With these electrodes use is made of impedance
transformers for reducing the high internal resistance of the electrodes. All signal lines
are connected in the terminal block of the amplifier basic unit (17); the signals
are processed by microprocessor-based amplifier modules for chlorine (16), pH value
(15) and Redox (14).
Option: These amplifier modules can be provided with an integrated controller for direct
control of dosing pumps or control elements.
A recorder (18) or a visual display device may be connected to the volt-free analogue
amplifier output singal.
A digital COM interface card (13) allows the transmission of measured data, on/off
conditions and error messages to a printer (19).
9
3.2
THEORY OF OPERATION
(see BZ-1150/1-5/E, fig. 2, 2A-2F)
The DEPOLOX 4 measuring cell consists of a 3-electrode system with external
potentiostatic closed-loop control. The working electrode and the counter electrode
(BZ-1150/3-5/E, fig. 2D, item 1 and BZ-1150/2-5/E, fig. 2B, item 2) of the half-ring type
are made of a platinum alloy. A silver/silverchloride electrode serves as reference
electrode (BZ-1150/2-5/E, fig. 2B, item 3); the contact between reference electrode and
sample water is established by two membranes (BZ-1150/2-5/E, fig. 2B, item 7). The
reference electrode is mounted in PVC brackets and completely submerged in electrolyte
(BZ-1150/2-5/E, fig. 2A/B, item 60). The electrolyte container is transparent, thus
enabling a visual check to be made of the amount of electrolyte in the reservoir.
Replenishment of the electrolyte is possible without shutting down the measuring cell
system. A membrane in the plug of the electrolyte reservoir provides the necessary
equalization of pressure (BZ-1150/2-5/E, fig. 2A, item 17).
The measuring cell is connected to a digital measuring amplifier which maintains an
adjustable constant potential (Upot) between working and reference electrodes by means
of potentiostatic closed-loop control.
About 33 l/hr of the water to be analysed flows past this system of electrodes. The
current generated in the measuring cell is directly proportional to the concentration of
the oxidising agent in the sample water. This current is then passed to the
microprocessor-based electronic system for processing.
The surfaces of the electrodes are continuously cleaned by a special kind of cleaning
grit in the electrode cell. The transparent plexiglass body of the cell makes it possible
to observe the circulation of the grit in the cell.
An integrated flow regulator (BZ-1141/E) ensures a constant sample water flow of about
33 l/hr.
If desired, electrodes for pH-value and Redox measurement can be inserted into the
two holes (BZ-1150/2-5/E, fig. 2A, item 48) in the removable cover of the measuring
cell. This means that the DEPOLOX 4 measuring cell can be augmented with extra
measuring devices without any additional piping.
The following features of the DEPOLOX 4 ensure accurate, repeatable measured
data and reduce the frequency of zero point recalibration:
- potentiostatic control
- continuous hydromechanical electrode cleaning system
- regulated sample water flow.
11
3.3
TEMPERATURE COMPENSATION
If temperature fluctuations in the sample water are expected to exceed ± 10°C (e.g. in
hot-whirl-pool systems), temperature compensation is recommended.
In this case the required Pt 100 temperature sensor is incorporated in the measuring
cell block.
In the range between 5 and 50°C, temperature compensation of the measured chlorine
residual is performed automatically prior to display. During automatic operation of the
analyser, the matrix display unit of the amplifier shows the temperature of the sample
water. Further processing of the temperature signal is only possible via the digital COM
interface card.
4.
INSTALLATION
4.1
LOCATION OF INSTALLATION
The DEPOLOX 4 unit should be protected from freezing temperatures, preferably
installed in a heated room. When installing the unit, it is very important to consider
both the chlorine contact time and mixing with the treated water.
POTABLE WATER
Adequate mixing of chlorine and water will be achieved if the distance between
the point of application and the sample water take-off point is at least 10 times
- preferably even 20 times or more - the diameter of the water line, e. g.
if the diameter of the water line is DN 300, the minimum distance will
be 300 mm x 10 = 3 m.
The contact time is the time that elapses between chlorine application and chlorine residual measurement. It is made up of both the flow time in the main line from the
point of application to the sample take-off point, and the flow time in the sample line
from the sample take-off point to the DEPOLOX 4. It is recommended that the sample
line be kept as short as possible.
If extended contact times, e.g. 5 to 15 minutes, are required, a contact tank can be
installed in the sample line directly before the measuring cell. It should be noted that
in this case a flow and residual control system must be used.
12
SWIMMING POOL WATER
The sample water take-off has to be installed in the return line to the pool. It
should be observed that the sample water has to be taken off before flocculation
agents are added and that the minimum pressure at the measuring cell must be
1.5 m head (0.15 bar).
These instructions are applicable to chlorine, chlorine dioxide and ozone.
The DEPOLOX 4 unit with amplifier should be mounted on a vertical wall, if possible
at eye level, by fastening it with the 4 bolts supplied in the 4 mounting holes in the
basic unit. Install the amplifier casing as close as possible to the measuring cell. The
connecting cable between the measuring cell and amplifier has a standard length of
1.5 m. If local conditions require it, use can be made of an extended cable (max. length:
50 m) via a plug socket. It is essential to use a screened cable. The signal line must
not be laid adjacent to any mains supply cable.
4.2
SAMPLE WATER TAKE-OFF
IMPORTANT!
Use a PVC hose (internal diameter 6 x 3) or a 6 mm PVC pipe for the sample
water line and locate the unit to minimize sample line length.
CAUTION:
Copper pipes must not be used for the sample water line. Locate
the sample water take-off to ensure optimum mixing of disinfectant
and water, a continuous sample water flow without air bubbles as
well as a constant pH-value in the range between 4 and 8.
Depending on the local sample water pressure, one of the several sample water
take-off assemblies available should be selected. The pressure at the inlet of the
DEPOLOX 4 analyser must be within a 0.15 to 4.0 bar g range. In this pressure range,
a constant water flow of 33 l/h is provided irrespective of pressure fluctuations.
Water pressures of 4.0 to 40 bar g have to be reduced to 2.0 to 4.0 bar g by means
of a pressure reducing valve at the sample water take-off. If the required minimum
pressure of 0.15 bar is not available, a sample water pump has to be installed
(BZ-1179/E, BZ-1165/E, BZ-1166/E and BZ-1167/E).
13
4.3
SAMPLE WATER DRAINAGE
After leaving the measuring cell via the drain hose (page 10, item 6), the sample water
flows to waste via the supplied drain funnel and a 15 mm PVC pipe (pressureless
drainage).
If the DEPOLOX 4 analyser cell used is of the pressure-resistant type, the back pressure
in the sample water return line must not exceed a maximum of 1.5 bar; the sample
water inlet pressure must always be 0.5 bar higher than the back pressure (max. inlet
pressure: 2 bar).
5.
STARTUP
5.1
DEPOLOX 4 ANALYZER (PRESSURELESS TYPE)
(BZ-1150/1-4/E, fig. 2A-2E)
1.
Unscrew nut (fig. 2A, item 46).
2.
Remove cover (fig. 2A, item 41).
3.
Pull electrode assembly down and out of cell block.
4.
Remove felt ring (transport protection of membrane).
5.
Exchange plug against separately supplied plug fitted with membrane for
venting of the electrolyte reservoir.
6.
Replace electrode assembly into cell block.
NOTE! Keying pin (fig. 2D, item 58) must snap into position.
7.
Allow sample to flow by opening linlet valve.
8.
Fill a half capful of grit (U-95 653) into the cell block.
9.
Replace cover and tighten by nut.
NOTE!
After a running-inperiod of about one hour measuring cell and amplifier
can be calibrated. A re-calibration should be made 24 hours after initial
calibration.
Air bubbles building up at the inner surface of the cell block and
preventing somewhat the rotation of the grit will disappear after a runingin period of about 24 to 48 hours.
14
5.2
DEPOLOX 4 ANALYZER (PRESSURE TYPE MAX 1.5 BAR)
(BZ-1150/5-5/E, fig. 2F)
1.
Unscrew nut (fig. 2F, item 62).
2.
Remove cover (fig. 2F, item 71).
3.
Pull electrode assembly down and out of cell block.
4.
Remove felt ring (transport protection of membrane).
5.
Exchange plug against separately supplied plug fitted with membrane for
venting of the elctrolyte reservoir.
6.
Replace electrode assembly into cell block.
NOTE! Keying pin (fig. 2D, item 54) must snap into position.
7.
Allow sample to flow by opening inlet valve.
8.
Fill a half capful of grit (U95 653) into the cell block.
9.
Repalce cover and tighten by nut.
5.3
AMPLIFIER FOR CHLORINE MEASURING CELL DEPOLOX 4
After completion of the field the following initial startup procedure has to be followed:
1.
Insert the amplifier module into the basic unit until it is firmly seated and
tighten fixing screws.
2.
As soon as power is on, an automatic test of the amplifier is made, which
is signalled by the flashing of all display segments.
3.
Check the factory-set amplifier setup against the following table. It does not
meet your requirements, reprogram the setup (refer to page 17, item 6). Press
the MANUAL/AUTOMATIC key scroll the parameter (P) and function (F)
menus by pressing keys "P" and "F" respectively. To switch from P to F
menu, press the MANUAL/AUTOMATIC key again (refer to page 34, item
11.5).
15
BASIC SETUP
Menu
Range RGE
Code
Option controller set value CSP
HI Alarm set
LO Alarm set
Limit time delay (Tv min.)
Hysteresis
HI/LO Alarm set
mA output signal
Selection cell
Bias volts
Operation
0...1.00 mg/l
904
0.45 mg/l
1.00 mg/l
0.00 mg/l
0.0 min
0.03 mg/l
- - - (switched off)
0...20 mA
DEPOLOX 4
250 mV
chlorination
F
P
P
P
P
P
P
P
P
P
P
P
A detailed description of the amplifier functions is contained in the chapter "Amplifier"
(page 34, item 11.5).
16
6.
CALIBRATION OF THE DEPOLOX 4 AMPLIFIER
IMPORTANT NOTE!
If the chlorination plant or the solution regulator is operated automatically, switch
from the automatic to manual operation mode prior to calibration or maintenance
of the DEPOLOX 4 amplifier. Press the MANUAL/AUTOMATIC key of the amplifier
- "Hd." will appear in the text display line. Activate the electric positioner of the
chlorinator by pressing the " " key.
As the water quality at individual locations may differ considerably, the calibration of
the DEPOLOX 4 analyser has to be carried out on site. As already mentioned, the
unit has to operate continuously for at least 24 hours before calibration can be
started.
After long duration shutdowns as well as after electrode cleaning or replacement,
the calibration has to be repeated and checked after 24 hours.
6.1
CALIBRATION OF RANGE
The factory calibration of the measuring range is 0 to 1.00 mg/l of free chlorine. Alternative ranges (500 ppb, 1.0, 2.0, 5.0 or 99.9 mg/l) can be programmed prior to zero
calibration and DPD calibration.
1.
2.
6.2
Press the MANUAL/AUTOMATIC key of the amplifier menu display then press
key "F" repeatedly until "RGE" for range is displayed.
Press direction keys to select the range and enter the final value by pressing
key "E".
CALIBRATION OF BIAS VOLTAGE
The factory calibration of the bias voltage is 250 mV. For ozone measurement as well
as for water, sea water or brine water, the bias voltage must be changed to 300 mV.
1.
2.
3.
4.
Activate manual operation mode ("Hd.") and press key "P" repeatedly until
"CODE" is displayed.
Press direction keys to select access code "904" and enter this code (key
"E"). All the following parameters can now be changed in the P menu.
Press key "P" until "Upot" is displayed.
Select the desired bias voltage by pressing the direction keys and enter the
final value (key "E").
17
6.3
ZERO CALIBRATION
1.
Activate manual operation mode and press key "F" until "ZRO mg/l" is
displayed.
Close shut-off valve (page 10, item 20) to shut off sample water flow and
wait for 3 minutes.
Press key "E" to enter the zero current.
Open shut-off valve.
Press the MANUAL/AUTOMATIC key to leave the F menu.
2.
3.
4.
5.
NOTE:
After the sample water flow is shut off, the indication of the amplifier with drop very fast initially then after about 1 minute more slowly.
During initial startup, a waiting period of 5 minutes must be observed even if the
digital display drops to 0.00 after a few seconds of flashes.
The potentiostatic measuring principle allows a 2 month interval between calibrations.
6.4
ZERO CALIBRATION WITH CHLORINE-FREE WATER
If chlorine-free water is available, it may be used for zero calibration. In some cases
(e.g. in waterworks) chlorine-free water for zero calibration may also be obtained by
turning off the chlorinator.
6.5
ZERO CALIBRATION IN CASE OF A COMBINATION OF
CHLORINE AND OZONE
If a combination of these two methods of treatment is used, the sample water for
checking and calibrating the zero point must be taken off after the activated carbon
filter of the ozonisation system. This means that there must be a second sample water
take-off after the activated carbon filter of the ozonisation system in addition to the
sample water take-off in the return line to the pool. Both sample water lines must be
coupled by means of a three-way ball valve before the measuring cell. In this way,
the sample water line can be used alternatively for measuring or zero-calibration
purposes.
18
6.6
MEASURED VALUE CALIBRATION
1.
After completing the zero calibration, open shut-off valve (page 10, item 20)
and wait at least 2 minutes.
2.
Activate manual operation mode and press key "F" until "DPD mg/l" is
displayed.
3.
Take a sample from the drain hose and determine the content of free
chlorine, chlorine dioxide or ozone by means of the DPD method (colorimetre
or photometer).
4.
Press direction keys until the determined value is displayed on the LED
display.
5.
Enter this value into the amplifier memory by pressing key "E". The measuring
cell is now calibrated.
6.
Leave the F menu and return to manual operation mode by pressing
MANUAL/AUTOMATIC key. Press this key again to switch to automatic
operation of the amplifier. The controller outputs (optional) are now activated.
6.7
CHEMICAL ANALYSING METHODS
The chemical determination of chlorine residual or other oxidising agents may be
performed conveniently by using either a colorimeter or a photometer. Both instruments
furnish precise values and are easy to handle. For chlorine and ozon measurements,
DPD tablets or DPD liquid have to be added to the water sample. The water colour is
subsequently checked against a colour chart or in the photometer (refer to the respective
instruction manuals).
To keep the measuring error as small as possible, compute the average
consecutive samples.
19
of
3
7.
MAINTENANCE
7.1
ZERO POINT AND MEASURED VALUE CHECK
After initial setup, the zero point and measured value should be checked periodically:
1.
Daily check of measured value with DPD method.
2.
Routine check of zero point (after 1 or 2 weeks).
3.
"Check after 24 hours" following electrode cleaning or replacement and/or
following replacement of grit.
7.2
SERVICING OF THE REFERENCE ELECTRODE
The silver/silverchloride reference electrode (BZ-1150/2-5/E, item 3) is screwed into an
electrolyte receptacle filled with electrolyte gel. Replenish the electrolyte as soon as the
electrolyte level has dropped to the sample water level in the flow-through assembly
(electrolyte U-95 655). A visual check is necessary only every 2 months.
In cases where the DEPOLOX 4 is used for water having a temperature above 35°C
(Hot-Whirl-Pools) the electrolyte for the reference electrode has to be renewed every
4-6 months, for normal applications every 12 months.
7.3
CHANGE OF GRIT
As the grains of grit (U-95 653) used for continuous electrode cleaning wear down after
a while, the grit has to be replaced every 2 months. Proceed as follows:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Activate manual operation mode.
Close shut-off valve (page 10, fig. 1, item 20) to shut off sample water flow.
Open drain valve (page 10, fig. 1, item 7 and BZ-1141/E, fig. 3, item 19)
of the DEPOLOX 4 measuring cell by turning the knurled-head screw
counterclockwise.
When the cell body is empty, close drain valve.
Unscrew PVC nut (BZ-1150/2-5/E, fig. 2A, item 46) and remove cover
(BZ-1150/2-5/E page 95, fig. 2A, item 39).
Pull electrode assembly down and out of the cell block (BZ-1150/2-5/E, fig.
2A, item 41) and rinse measuring cell and cell block to remove grit particles.
Replace electrode assembly into cell block.
NOTE! The keying pin must snap into position.
Pour half a capful of grit into the cell block. (Use cap of spare grit glass).
Fasten cover (BZ-1150/2-5/E, fig. 2A, item 39) with nut (BZ-1150/2-5/E, fig.
2A, item 46).
Open shut-off valve (page 10, fig. 1, item 20).
20
7.4
STRAINER
The strainer (page 10, fig. 1, item 3) should be cleaned periodically depending on the
local water quality. The frequency of cleaning should be determined locally as required.
7.5
ELECTRODES
As grit is used for cleaning the working electrode and the counter electrode, these wear
down gradually.
The electrodes should be replaced every 3 or 4 years. The reference electrode and
the KCL electrolyte should be replaced every year (chapter 7.2). In the case of
extended shut-downs, for example during the winter season of outdoor swimming pools,
the KCL electrode as well as the pH and Redox probes are to be protected against
frost.
The correct assignment of the measuring cables to the probes is shown on drawing
BZ-1145.
Refer to drawing F-90 604 for correct matching of measuring cables and
electrodes.
7.6
CHEMICAL AND MECHANICAL CLEANING
If there is a build-up of deposits in the flow-through assembly (BZ-1150/2-5/E, item 41)
or on PVC parts, they may be removed by cleaning with dilute hydrochloric acid
(concentration approx. 10 %, U-94 726).
CAUTION:
Do not clean the working electrode and the counter electrode
chemically!
The two membranes (BZ-1150/2-5/E, fig. 2B, item 7) for the reference electrode cannot
be cleaned. Use a pair of pointed pincers to remove the membranes together with their
PVC body by gently pulling and turning, and to replace them.
Depending on the local water quality, the membranes should be replaced every 2 to 3
years.
7.7
SPARES FOR MAINTENANCE
Pt working electrode, UXB-95 818
Pt counter electrode, U-95 614
Reference electrode, U-95 626
Membrane, U-95 641
0.1 l of electrolyte for reference electrode, U-95 949
25 g of grit, U-95 653
21
8.
TROUBLESHOOTING
PROBLEM
Insufficient sensitivity
CAUSE
REMEDY
Insufficient water flow.
Check water flow, remove any
contaminants in sample water line
or in measuring cell, clean strainer.
Contaminated electrodes.
Clean electrodes.
Changed grit colour
(yellow/brown).
Replace grit.
Excessive pH-value
Adjust pH-valve.
Unsteady signal.
Membrane clogged. Air
Replace membrane. Wait until
bubbles on inner surface of running-in period of measuring cell
membrane.
is completed.
Calibration of zero
point and measuring
range not possible.
Excessive zero current.
Measured electrode current (menu
item µA electrode current) in
chlorine-free water must be below
± 5 µA; otherwise verify bias
voltage = 250 mV (chapter 6.2).
Insufficient measuring cell
current.
The current potential between
chlorine-free and chlorinated water
with 1.0 mg/l of chlorine must be at
least 4 µA; contaminated
electrodes or the presence of
chlorisocyanurates in the water
might be the cause of a lower
potential.
Indicated value
Considerable fluctuations in Check pressure.
oscillates considerably water pressure.
at constant chlorine
concentration.
Fluctuating pH-value.
Clean pH electrodes.
Inlet to cell body or flow
regulator clogged.
Clean inlet or flow regulator.
Diaphragm defective.
Replace diaphram.
Air bubbles.
Install vent line.
22
9.
pH-VALUE ANALYSER
The pH-value analyser consists of a pH probe, an impedance transformer, a special
cable and a plug-in amplifier. For combined chlorine and pH-value measurement, the
transparent cell block of the DEPOLOX 4 chlorine measuring cell serves as flow-through
assembly. If only the pH-value has to be measured, a special flow-through assembly
is available.
9.1
pH-PROBE WITH SPECIAL CABLE
The pH probe is equipped with a ceramic membrane and a silver/silver chloride
reference potential. The 3.0 mol KCL gel electrolyte does not require replenishment.
NOTE! Do not remove the hose from the filling hole.
The pH probe is equipped with a special connector. Check that the o-ring is still on
the unit prior to connection. An impedance transformer (part no. U-95 607) has to be
fastened to the pH probe, which, in turn, is plugged into the measuring cell cover. This
impedance transformer is used to convert the very high ohmic signal of the pH probe
(appr. 1000MOhm) into a low ohmic signal so that problems caused by dirt, moisture
or electric fields around live wires can be avoided to a large extent.
By virtue of the incorporated lithium battery, the impedance transformer does not have
to be connected to an external power source (battery life: approx. 5 years). The max.
distance is 50 m.
9.2
START-UP OF pH-VALUE ANALYSER
1.
Plug the pH probe into the DEPOLOX 4 measuring cell cover, fasten the
impedance transformer to the probe and the probe cable with plug to the
impedance transformer.
2.
Connect the probe cable to the corresponding terminals in the basic unit.
3.
Plug the pH amplifier into the basic unit and fasten it.
Check the standard factory calibration of the amplifier and change the settings if
necessary. Press key MANUAL/AUTOMATIC, then scroll the parameter and function
menus by pressing key P and key F respectively.
23
BASIC SET-UP
Temperature
Range zero point ZRO
Range final value RGE
Code
Setpoint (control contact)
HI Alarm set
LO Alarm set
Direction of control
Limit value time delay
Limit value hysteresis
Alarm relay
mA output signal
20°C
pH 4.00
pH 9.00
904
7.00 pH
9.00 pH
4.00 pH
"ACID"
0.00 min
0.03 pH
N.O.
0-20 mA
Menu
F
F
F
P
P
P
P
P
P
P
P
P
4.
Press key MANUAL/AUTOMAITC - "Man. pH" is displayed.
5.
If the pH-amplifier is not fitted with an automatic temperature compensation
(option Pt100), after pressing the F-key the menu "Com. °C" is displayed.
Prior to the calibration of zero point and slope the sample water temperature
must be entered.
6.
Press key "F" until "Cal. pH7" for calibration with buffer solution pH is
displayed.
7.
Remove pH probe from Depolox 4 cell, immerse it in pH 7 buffer solution
and agitate gently.
8.
As soon as the digital display has stabilized, press key "E" to enter calibration
value pH 7 (display: 7.00 pH).
9.
Press key "F" until "Cal. pH" is displayed. For slope calibration use either
the pH 4.65 buffer solution recommended by W&T or another type of solution,
e.g. pH 9 buffer solution.
Rinse probe with distilled water between calibrations!
10.
Immerse probe in pH 4.65 buffer solution and agitate gently.
11.
As soon as the display has stabilized, select the pH value of the buffer
solution (e.g. 4.65) on the display by pressing the direction keys.
12.
Press key "E" to enter the slope value.
13.
Replace pH probe into DEPOLOX 4 cell block.
24
9.3
MAINTENANCE OF pH PROBE
Depending on the degree of contamination of the sample water, the pH probe has to
be cleaned in regular intervals. The frequency of cleaning has to be determined
empirically, but it is recommended to clean or calibrate it every 4 weeks. To prevent
incorrect measurement, both the glass diaphragm and the ceramic membrane have to
be cleaned.
Clean the glass diaphragm mechanically with a moistened, clean and soft napkin
or cotton swab.
Do not clean the probes with a dry napkin or cotton swab as this method tends to
produce a uniform cover of dirt on the probe surface.
Remove oil or grease with acetone, denaturated alcohol or another type of solvent. After cleaning it, rinse the probe thoroughly with water.
To remove calceous deposits from the glass diaphragm and the membrane, submerge
the probe in hydrochloric acid of 10 % strength. Rinse thoroughly with distilled water.
Probe ageing is frequently the cause of a sluggish pH-value indication or a declining
slope. pH-probes have a service life of 1 to 3 years provided that they are serviced
regularly.
9.4
pH MEASUREMENT USING THE PHENOL RED METHOD
Checks of the pH-value by means of comparators or photometers using the phenol red
method may show deviations of 0.5 pH units between the value displayed on the
DEPOLOX 4 amplifier and the value obtained from the sample water discharge from
the DEPOLOX 4. The cause for such a deviation is the degassing of carbonic acid in
the sample water drain hose.
For comparative measurements the sample water should be taken through the
drain valve. Do not forget to shut the drain valve after drawing with the sample.
25
9.5
SPARE PARTS AND CHEMICALS FOR MAINTENANCE
For the maintenance of pH probes, a complete service case is available (order no. U93 395). Any item in the service case may also be ordered separately.
pH probe, order no. U-95 690
with impedance transformer, order no. U-95 607
and pH/mV cable, order no. U-93 838
standard buffer solution pH 7.00,
supplied in a 250 ml glass bottle
order no. EXA-100 277
standard buffer solution pH 4.65,
supplied in a 250 ml glass bottle
order no. EXB-100 277
squeeze bottle made of polyethylene
filled with 500 ml of distilled water,
order no. U-93 426
filter paper, order no. U-93 429
100 ml of hydrochloric acid,
strength 10 % supplied in a PE bottle,
order no. U-93 427
100 ml of denaturated alcohol supplied in a PE bottle,
order no. U-93 428
calibration beaker made of polypropylene, 100 ml, graduated,
order no. P-93 700
26
10.
REDOX ANALYSER
The Redox analyser consists of a Redox probe, an impedance transformer, a special
probe cable and a plug-in amplifier. For combined chlorine and Redox measurement,
the transparent cell block of the DEPOLOX 4 chlorine measuring cell serves as flowthrough assembly. If only the Redox value has to be measured, a special flow-through
assembly is available.
10.1
REDOX PROBE WITH SPECIAL CABLE
The Redox probe is equipped with a ceramic membrane and a silver/silver chloride
reference potential. The 3.0 mol KCL gel electrolyte does not require replenishment.
NOTE! Do not remove the hose from the filling hole.
The Redox probe is equipped with a special connector. Check that the o-ring is still
on the unit prior to connection. Also with the Redox probe, an impedance transformer
is used to convert the very high ohmic signal into a low ohmic signal. The supplied
screened coaxial cable of 1.5 m length is equipped with a special plug on one end.
Fasten this plug to the impedance transformer connector unit. The other end of the
screened cable has to be connected directly to the corresponding terminal in the basic
unit. The max. distance is 50 m.
10.2
START-UP
The start-up procedure for the Redox analyser is the same as that for the pH-value
analyser.
A solution that generates 468mV (Pt Ag/AgCl, 3 mol KCL, E-100 278) serves as buffer
solution.
Immerse the probe in this solution and wait for 10 minutes. Activate manual operation
mode, press key "F" until "Cal. mV" is displayed and select the buffer solution value
by pressing the direction keys. Press key "E" to enter this value (max. ± 50 mV).
The Redox probe is now calibrated. The factory settings are similar to those in the pH
amplifier, the factory-set measuring range is 400...900 mV.
NOTE:
The running-in of a Redox probe takes several hours. This factor has to be taken
into consideration to achieve a correct Redox measurement.
27
Basic set-up
(Redox amplifier without PID controller)
Range zero point ZRO
Range final value RGE
Code
Setpoint (control contact)
Control direction
HI alarm set
LO alarm set
Limit value time delay
Hysteresis
Alarm relay
mA output signal
10.3
400 mV
900 mV
904
700 mV
INCR.
900 mV
400 mV
0.00 min
3 mV
N.O.
0-20 mA
MENU
F
F
P
P
P
P
P
P
P
P
P
MAINTENANCE OF THE REDOX PROBE
Depending on the degree of contamination of the sample water, the Redox probe should
be cleaned in regular intervals (see maintenance of pH probe).
A contaminated probe will respond sluggishly as indicated by an almost straight line
on the recorder tape. Often the indicated Redox potential is too low.
Usually the surface of the platinum electrode is gradually covered up by a layer of
contaminants which may not be visible. The ceramic membrane may also be
contaminated or scaled by calceous deposits.
Remove the Redox probe from the flow-through assembly and clean the platinum electrode with water and some fine abrasive household cleaning powder. Take
a bit of cleaning powder and rub the platinum electrode between your finger tips until
it becomes shiny. Rinse thorougly with water and replace the probe without touching
the platinum electrode.
After a running-in period of 3 to 4 hours, the probe will again be ready for
operation.
To remove calceous deposits, immerse the probe for a few minutes in hydrochloric
acid (strength 10 %) just beyond the membrane. Rinse thoroughly with water.
Remove oil and grease with denaturated alcohol or acetone. Rinse probe thoroughly
with water.
28
10.4
SPARE PARTS AND CHEMICALS FOR MAINTENANCE
mV-Redox probe, order no. U-95 691
with impedance transformer, order no. U-95 607
and pH/mV cable, order no. U-93 838
Redox control solution + 468 V (for Ag/AgCl 3 mol KCL),
supplied in a 250 ml glass bottle
order no. E-100 278
calibration beaker made of polypropylene, 100 ml, graduated,
order no. P-93 780
squeeze bottle made of polyethylene, filled with
500 ml of distilled water, order no. U-93 426
100 ml of hydrochloric acid, strength 10 %,
supplied in a PE bottle, order no. U-93 427
100 ml of denaturated alcohol, supplied in a PE bottle,
order no. U-93 428
29
11.
AMPLIFIER
11.1
INSTALLATION
Mount the basic unit (dimensions W 337 x H 223 x D 223 mm) in the 4 mounting
holes. If the front door is closed, the enclosure is IP 65.
A maximum of 3 plug-in amplifiers and 1 COM interface card can be plugged into the
basic unit. The amplifiers can be combined in any desired way (e.g. 2 chlorine amplifiers
and 1 pH amplifier).
A basic unit for panel mounting of 3 amplifiers and 1 COM interface card is also
available (dimensions: see drawing U-95 649, U-95 820 and U-95 822).
The plug-in amplifiers (dimensions: W 76 x H 129 x D 160 mm) consist of a front
panel with keypad and 2 printed circuit boards (standard European dimensions: 100 x
160 mm).
As a result of the modular design, each amplifier has a separate power supply and a
separate microprocessor. In the event of a failure of one measuring system, the function
of the remaining amplifiers is not impaired. In this case, the unit can be repaired in a
quick and inexpensive way by the customer himself as he only has to replace the
defective amplifier.
Loosen the 4 mounting screws and pull the amplifier out of the basic unit.
The COM interface card (dimensions: W 20 x H 129 x D 160 mm) for data transmission
between amplifier and a printer or a PC has to be plugged into the first receptacle on
the right.
Any receptacle (amplifier or interface card) not in use has to be covered with a blind.
30
11.1.1
DIMENSIONS OF BASIC UNIT, PLUG-IN AMPLIFIERS AND
COM INTERFACE CARD
B-74.PCX - edition 01/1993
Basic unit for wall mounting
Plug-in amplifier
COM-Interface card
B-75.PCX - edition 01/1993
Order No. for amplifiers: refer to table BZ-1245-E.
31
11.2
ELECTRICAL INSTALLATION
Unit for panel mounting: see W/D 30-E-7578, sheets 1 and 2.
Connect the mains power supply to terminals L/N/PE for the supply of all plug-in
modules. A 16 A protecting fuse for the mains power supply must be provided.
The current flows via the basic unit PCB to the terminal blocks of the plug-in units.
CAUTION!
The terminal blocks may carry the mains voltage even after the
plug-in units have been removed.
The plug-type terminals in the basic unit may be removed temporarily for easier
connection.
On the power supply PCB, a fuse (230V, 0.125 A or 115 V, 0.25 A) is provided for
each plug-in amplifier.
Terminals 9, 10, 11 and 12 for the connection of dosing pumps or an electric positioner
can only be used if option "controller" has been selected and are protected by a fuse
on the basic unit PCB (F1, F2, F3).
Careful wiring by trained personnel is essential to prevent electrical destruction of the
amplifier modules.
Wiring diagram 30-E-7585, sheets 1-3 shows a wiring example for combined Cl2, pH
and Redox control with an electric positioner or a dosing pump.
32
11.3
FRONT PANEL
measured value display
LED’s for controller
output (optional)
text display
temperature display (optional)
keypad
handle with designation
4 mounting screws
B-45.PCX - edition 01/1993
The front plate design is the same for all amplifiers. The front plate consists of a
3-digit 7-segment LED measured-value display, a text display (5 x 7 dot matrix) and a
keypad with 6 keys. If the options "controller" and "temperature" have been selected,
additional LED’s show the direction of rotation of the controller output (increasing and
decreasing feed rate of electric positioner) and the temperature of the sample water in
°C.
Texts can be displayed in 4 languages (German, English, French and Italian), which
facilitates the operation of the amplifiers considerably.
33
11.4
KEYPAD
parameter menu
Parameters such as limit values,
mA output or, if option "controller"
has been selected, controller
parameters are set in the P menu.
function menu
Settings such as zero point,
measured value and measuring
range can be set in the F menu.
They are used to select values in
the P or F menus and for the
manual operation of controller
outputs.
direction keys
key MANUAL/
AUTOMATIC
Activates manual operation mode
required for selection of values in
the P or F menus.
key "E"
If settings in the P or F menus are
changed (e.g. limit value increased
from 0.30 to 0.35 mg/l), the
selected value has to be entered
by pressing key "E".
B-18.PCX - edition 01/1993
11.5
PARAMETER AND FUNCTION MENUS SET-UP AND CHANGING OF SETTINGS
1)
Press key
MANUAL/AUTOMATIC:
"Hd." is displayed in the text display,
manual operation mode of ampflifier is
activated.
2)
Press keys "P" or "F":
The respective menus are displayed in
the text display.
Press key again to scroll menu.
3)
Press direction keys:
Values to be changed can be selected.
4)
Press key "E":
The selected value is entered.
5)
Press key
MANUAL/AUTOMATIC:
Return from F or P menus to manual
operation mode.
34
11.6
BASIC AMPLIFIER SET-UP
The German set of characters is used as standard in the matrix text display. For
changing this configuration (switch S1 on processor PCB), the amplifier has to be
removed from the basic unit. Use switches 1 and 2 to select the language and switch
3 to activate option "temperature" (temperature measurement with Pt 100). Together
with the COM interface card, switch 4 is used to set date and time. Switches 5 and 6
serve internal servicing purposes.
Switch no. 5 is used to unlock the positioner's feedback signal for the Cl2 amplifier.
Switch no. 6 serves internal servicing (Reset). (See chapter 15, page 50.)
B-22.PCX - edition 01/1993
German
English
French
Italian
Switch M1 number 1
Switch M1 number 2
OFF
OFF
ON
OFF
OFF
ON
ON
ON
Switch M1 number 3
ON:
OFF:
Option Pt 100 temp. measurement acitvated
Option Pt 100 temp. measurement inactivated
Switch M1 number 4
ON:
OFF:
Date-time can be selected (COM-interface)
Date-time selection locked
Switch M1 number 5
ON:
OFF:
Positioner feedback for Cl2 module
No positioner feedback
Switch M1 number 6
Reset (see chapter 15; error message;
System? or ADU?)
The basic set-up (factory-set) of the parameter and function menus for chlorine,
pH-value and Redox measurement amplifiers is described on pages 15, 23 and 27
respectively.
35
12.
CHLORINE MEASUREMENT AMPLIFIER
12.1
PARAMETER MENUS (STANDARD CL2 AMPLIFIER)
TEXT DISPLAY
DESCRIPTION
POSSIBLE SETTINGS
CODE
Prevention of unauthorized Access code: 904
access to following menus.
SP = mg/l
Desired value displayed
only if option "controller"
has been selected.
All settings in the selected
measuring range (F menu).
HI Alarm
Settings between limit value min
and end of measuring range.
LO Alarm
Settings between 0.00 and limit
value max.
Limit time delay
0...60 min.
Limit hysteresis
Settings between 1...50 digits of
display
Alarm relay condition
N.O. = normally open
N.C. = normally closed
--- switched off
Selection of mA output
0...20 / 4...20 / 0...5 / 0...10 mA
--- switched off
DEPOLOX 4
Selection cell
Depolox 3, Depolox 4
Upot
Bias voltage
50 mV... 999 mV
Direction of contact
Chlorination
Dechlorination
Control element selection
menu
EL. POS.
M. Pump
SOL. Pump
CONT.
Al
= mg/l
Al
= mg/l
Ald (min)
Alh (min)
Al N.O.
0...20 mA
CHLOR
EL. POS.
-
Electric positioner
Metering pump
Solenoid pump
Continuous output
NOTE: For the Cl2-amplifier the option "Controller" may be ordered. For this
option the extended parameter menus are valid.
36
EXTENDED PARAMETER MENU (Cl2 AMPLIFIER WITH CONTROLLER)
Selected control element:
electric positioner or motorized valve
(3-point step controller)
Ym (%)
Tuning of feedback signal
Automatic tuning of the feedback
signal and measurement of Ty
Xp (%)
Controller parameter
Prop. band 1...999 %
Ty (sec)
Running time of electric
positioner
Running time 10-180 sec.
Tn (min)
Controller parameter
Integral action time 1...9.99 min
Selected control element:
metering pump (pulse duration control)
Xp (%)
Controller parameter
Prop. band 1...199 %
Tp (s)
Controller parameter
Controller on-time + off-time =
cycle 10...120 sec.
Ymin (%)
Controller parameter
0...30 % basic load
Ymax (%)
Controller parameter
Controller output limit Ymin...100 %
Tn (min)
Controller parameter
Integral action time 1...9.99 min.
Selected control element:
solenoid pump or continuous controller output
(pulse frequency controller)
Xp (%)
Controller parameter
Prop. band 1...999 %
Ymin (%)
Controller parameter
0...30% basic load
Ymax (%)
Controller parameter
Controller output limit Ymin...100 %
Tn (min)
Controller parameter
Integral action time 0...99.9 min.
37
12.2
FUNCTION MENUS (CL2 AMPLIFIER)
TEST DISPLAY DESCRIPTION
POSSIBLE SETTING
ZRO mg/l
Zero calibration
Sets zero point at 0.00 mg/l
DPD mg/l
Measured value calibration
Sets value determined by DPD
method
RGE mg/l
Selection measuring range
1.00 / 2.00 / 5.00 / 9.99 mg/l
500 ppb
± µA
Display of cell current in µA
-5 ... +200 µA
DAY
MONTH
YEAR
HOUR
MINUTE
Parameters for COM-interface
(realtime clock) switch S1-4
(refer to chapter 11.6)
01...31
01...12
00...99
00...23
00...59
12.3
PARAMETER SET-UP DURING INITIAL OPERATION
NOTE:
The following settings are reference values for the initial operation of a Cl2
residual control system. The quality of regulation may be optimized by the user
himself with the help of a recorder.
It is essential to change only one controller parameter at a time and to check
the result after 2 to 3 days on the recorder tape.
It is recommended to change the prop. band Xp first and then the D-factor. It is
advisable to write the optimal user-specific values in the parameter and function
menus into the provided sticker in the terminal cover.
By measuring the dead times using a stop watch it is also possible to have the
controller parameters calculated automatically by the amplifier-controller (autoadaptation).
38
12.3.1
CONTROL ELEMENT ELECTRIC POSITIONER OR REGULATING
VALVE
Swimming pool water:
Controller
parameter
Children’s pool
Indoor bath
Swimmers’ pool
Indoor bath
Swimmers’ pool
Outdoor bath
Volume 90 m3
Dead time 10 min
Volume 900 m3
Dead time 12 min
Volume 175 m3
Dead time 3 min
(vertical throughflow)
Raise time:
40 min
Raise time:
280 min
Raise time:
40 min
Cl2 feed rate
max. 100 g/h
Cl2 feed rate
max. 450 g/h
Cl2 feed rate
max. 900 g/h
SP
0.50 mg/l
0.45 mg/l
0.40 mg/l
Xp
75 %
12 %
22 %
Tn
64 min
52 min
14 min
Controller
parameter
Potable water
SP
0.2 mg/l
Xp
100 %
Tn
2 min
Ty
180 sec.
39
12.3.2
CONTROL ELEMENT METERING PUMP, SOLENOID PUMP,
CONTINUOUS OUTPUT
Controller
parameter
Indoor bath swimming pool 100 m3
Cl2 feed rate D10 - 10 l/h
SP
0.50 mg/l
Xp
10 %
Tp*
60 sec
Ymin
0 %
Ymax
100 %
Tn
20 min
* Recommended Tp time for metering pumps
Metering pump
(storkes/min)
Tp (s)
- 20
120
20 - 40
40 - 80
100
60
80 - 125
30
125 - 200
15
NOTE:
Tp menu is not available when solenoid pump or continuous output are used as
control element.
40
12.4.3
ADJUSTMENT OF THE FEEDBACK DISPLAY
In order to compensater for tolerances and possible limitations of the electric positioner
the feedback display must be tuned.
Preconditions:
-
Electric positioner is in the AUTO position (handwheel engaged).
Running time of electric positioner 0..180 sec.
Electric interlocks of positioner must be inactivated.
Correct electric connection between positioner and amplifier.
Adjustment:
-
-
Select P menu "Ymin (%)".
Press key E.
Now the automatic adjustment of the feedback display is made. This can be seen
on the status display 1 till 6:
Ym (%) 1
activation
Ym (%) 2
0 % approach
Ym (%) 3
0 % tuning
Ym (%) 4
100 % approach
Ym (%) 5
100 % tuning
Ym (%) 6
calculation of positioner running time Ty
The tuning process is finished when the status display "Ym (%)" extinguishes.
Tuning tolerances:
The feedback signal is adjustable by max. 30 % at the zero
(Y 0 %) and range (Y 100 %) values.
Example 1 (potentiometer feedback):
Potentiometer 100 Ohm:
max. range 0...100 Ohm
min. range 30...70 Ohm
For feedback signals potentiometers in the range between
100 Ohm and 10 kOhm can be used.
Example 2 (mA feedback):
max. range 0...20 mA
min. range 6...14 mA
The ohmic load is 12 Ohm.
42
13.
pH MEASUREMENT AMPLIFIER
13.1
PARAMETER MENU (STANDARD pH AMPLIFIER)
TEXT DISPLAY
DESCRIPTION
POSSIBLE SETTINGS
CODE
Prevention of unauthorized
access to following menus
Access code: 904
SP pH
Desired value (contact)
All settings in the selected
measuring range (F-menu)
Al
= pH
HI alarm
Settings from limit value min to
top value of measuring range
Al
= pH
LO alarm
Settings from bottom value of
measuring range to limit value
max
Ald pH
Limit time delay
0...60 min
Alh pH
Limit hysteresis
1...50 digit of display
Al N.O.
Alarm relay
N.O. = normally open
N.C. = normally closed
--- switched off
0...20 mA
Selection of mA output
0...20 / 4...20 / 0...5 / 0...10 mA
--- switched off
ACID
Direction of control
Acid, alkaline
M. Pump
Control element selection menu
Solenoid pump, continuous
output, electric positioner,
metering pump
NOTE:
For pH-amplifier the option "Controller" may be ordered. For this option the
following parameter menus are valid.
43
EXTENDED PARAMETER MENU (pH AMPLIFIER WITH CONTROLLER)
Control element:
electric positioner or motorised valve
(3-point step controller)
Xp (%)
Control parameter
Prop. band 1...999 %
Ty (sec)
Running time of electric
positioner
Running time 10...180 sec
Tn (min)
Control parameter
Integral action time 1...99.9 min
Control element:
metering pump (pulse duration control)
Xp (%)
Control parameter
Prop. band 1...999 %
Tp (s)
Control parameter
Controller on-time + off-time
(cycle) 10...120 sec
Ymin (%)
Control parameter
0...30 % basic load
Ymax (%)
Control parameter
Controller output limit Ymin...100 %
Tn (min)
Control parameter
Integral action time 1...99.9 min
Control element:
Solenoid pump or continuous controller otuput (pulse
frequency controller)
Xp (%)
Control parameter
Prop. band 1...999%
Ymin (%)
Control parameter
0...30 % basic load
Ymax (%)
Control parameter
Controller output limit Ymin...100 %
Tn (min)
Control parameter
Integral action time 1...99.9 min
44
13.2
FUNCTION MENU (pH-AMPLIFIER)
TEXT
DISPLAY
DESCRIPTION
POSSIBLE SETTINGS
COMP °C
Internal temperature
compensation
0...99°C
(An external Pt 100 sensor
(0...50°C) can be connected
as an option.)
CAL pH 7
pH 7.0 calibration
(zero point)
Calibration only with buffer
solution pH 7.0.
CAL pH
pH calibration (slope)
Any buffer solution, e.g. pH 4.65
or 9, can be used.
ZRO pH
Bottom value of
measuring range
pH 0...5
RGE pH
Top value of measuring
range
pH 9...14
mV
Display of probe voltage
± 500 mV
DAY
MONTH
YEAR
HOUR
MINUTE
Parameters for COM
interface (realtime clock),
switch S1-4 (chapter 11.6)
01...31
01...12
00...99
00...23
00...59
* COMP °C is not displayed if the pH measurement amplifier is equipped with option
"Pt 100". In this case the external temperature signal of 0...50°C is used.
45
13.3
SET-UP OF CONTROL PARAMETERS FOR INITIAL OPERATION (PARAMETER MENU)
13.3.1
FOR METERING PUMPS (PULSE DURATION OR CONTINUOUS
CONTROLLER)
SP
Xp
Tp
Ymin
Ymax
Tn
=
=
=
=
=
=
13.3.2
FOR SOLENOID PUMPS (PULSE FREQUENCY CONTROLLER)
SP
Xp
Ymin
Ymax
Tn
=
=
=
=
=
13.3.3
FOR ELECTRIC POSITIONERS AND REGULATION VALUES
(STEP RATE CONTROLLER)
W
Xp
Ymax
Tn
=
=
=
=
pH 7.20
10 %
60 s
0 %
100 %
20 min
pH 7.20
10 %
0 %
100 %
20 min
pH 7.20
10 %
100 %
20 min
Setpoint
Control amplification (factor 10)
Pump cycle (ON + OFF time)
No basic load
No max. feedrate limit
Integral action time
Setpoint
Control amplification (factor 10)
No basic load
No max. feedrate limit
Integral action time
Setpoint
Control amplification (factor 10)
No reduction of the positioning speed
Integral action time
For all types of controllers the direction of control (ACID or ALKALINE) must be
selected. In the case of acid dosing (decreasing the pH 9) "ACID" must be selected.
46
14.
REDOX MEASUREMENT AMPLIFIER
14.1
PARAMETER MENU (STANDARD REDOX AMPLIFIER)
TEXT
DISPLAY
DESCRIPTION
POSSIBLE SETTINGS
CODE
Prevention of unauthorized
access to following menus
Acces code 904
SP = mV
Setpoint (contact)
All values in the selected
range (F menu)
Al
= mV
HI alarm
Settings from limit value
min to top value of
measuring range
Al
= mV
LO alarm
Settings from bottom value
of measuring range to limit
value max
Ald (min)
Limit time delay
0...60 min
Alh mV
Limit hysteresis for metering
and alarm contact
1...50 digits of display
Al N.O.
Alarm relay
N.O. = normally open
N.C. = normally closed
--- switched off
0-20 mA
Selection of mA output
0...20/4...20/0...5/0...10 mA
--- switched off
INCREASE/
DECREASE
Direction of control
Control upwards or
downwards
M. PUMP
Control element selection menu
Solenoid pump, continuous
output, electric positioner,
metering pump
NOTE:
For Redox-amplifier the option "Controller" may be ordered. For this option the
following parameter menus are valid.
47
EXTENDED PARAMETER MENU (REDOX AMPLIFIER WITH
CONTROLLER)
Control element:
electric positioner or motorised valve
(Redox amplifier with controller)
Xp (%)
Control parameter
Prop. band 1...999 %
Ty (sec)
Running time of electric
positioner
Running time 10...180 sec
Tn (min)
Control parameter
Integral action time
1...99.9 min
Control element:
metering pump (pulse duration control)
Xp (%)
Control parameter
Prop. band 1...999 %
Tp (s)
Control parameter
Controller on-time + off-time
(cycle) 10...120 sec
Ymin (%)
Control parameter
0...30 % basic load
Ymax (%)
Control parameter
Controller output
limit Ymin...100 %
Tn (min)
Control parameter
Integral action time
1...99.9 min
Control element:
Solenoid pump or continuous controller otuput
(pulse frequency controller)
Xp (%)
Control parameter
Prop. band 1...999%
Ymin (%)
Control parameter
0...30 % basic load
Ymax (%)
Control parameter
Controller output limit
Ymin...100 %
Tn (min)
Control parameter
Integral action time
1...99.9 min
48
14.2
FUNCTION MENU (REDOX-AMPLIFIER)
Text
display
Description
Possible settings
CAL. mV
Electrode calibration
Use Redox buffer solution
(468 mV)
ZRO mV
Bottom value of measuring
range
0...700 mV
RGE mV
Top value of measuring
range
300...999 mV
mV
Display of probe voltage
± 500 mV
DAY
MONTH
YEAR
HOUR
MINUTE
Parameters for COM interface
(realtime clock), switch S1-4
(refer to chapter 11.6)
01...31
01...12
00...99
00...23
00...59
49
15.
ERROR MESSAGES
The following table shows and explains all the possible fault messages which may
appear on the dot-matrix display.
If several erros occur at the same time, the error messages are displayed successively
and repeated cyclically.
Once the fault has been cured, the measuring system automatically erases the message
from the dispaly.
ERROR MESSAGE
CAUSE
REMEDY
Flashing display
measured value
"mg/l", "pH" or
"mV"
Measured value outside
measuring range.
Select bigger range.
Check calibration.
*ZRO?
Wrong connection of
measuring cell cable/max.
zero point compensation
exceeded (± 5 µA for
Depolox 4 and > + 100 µA
for Depolox 3 systems).
Check connection cables
and measuring cell current.
(Data sheet BZ-1145)
*DPD?
Slope error in chlorine
measurement amplifier.
The difference between zero
current and measured value
is below 4 µA (min. value
required for slope calibration
of full range).
The max. current of 100 µA
for Depolox 3 and 200 µA
for Depolox 4 is exceeded.
Check measuring cell;
clean electrodes;
replace electrolyte;
check pH value of sample
water (< pH 8?);
check presence of
chlorisocyanurates (Cl2
stabilizer) in sample water.
*CAL.?
In the pH amplifier, the
Check electrode,
tolerance of ± 100 mV was
impedance transformer,
exceeded during pH 7.0
measuring cable and buffer
calibration (intersection of solution (use fresh solution!)
isothermal lines) or the
Replace electrodes.
tolerance of ± 4mV/ pH-value
was exceeded during slope
calibration (e.g. with pH 4.65
buffer solution).
In the Redox amplifier, the
tolerance of ± 50mV was
exceeded during calibration
with 468 mV buffer solution.
50
ERROR MESSAGE
CAUSE
REMEDY
*µA?
The meausring cell current
of DEPOLOX 3 or 4 is
outside the limits of
- 5 µA...+ 200 µA
Check concentration of
chlorine in sample water
(> 10 mg/l?)
Check measuring cell
(short circuit)
DEPOLOX 4: check bias
voltage in P menu.
*mV?
The voltage of pH-value or
Redox electrode is outside
the limits of pH 0..14 /
Redox 0...1000 mV
Check electrode connections
(cable poles, correct
matching of electrodes and
amplifiers, e.g. pH electrode
connected to pH amplifier).
*mA?
Excessive ohmic resistance.
The amplifier cannot drive
the impressed mA output
current through the
connected current loop
(500 Ohm at 20 mA)
Check whether mA signal
is required (e.g. for recorder).
If not, inactivate output
signal by selecting "- - -"
in the P menu, parameter
selection "mA".
Admissible ohmic resistance:
4...20 mA - 500 Ohm
Check mA-signal cable for
0...10 mA - 1000 Ohm
discontinuities.
0... 5 mA - 2000 Ohm
*CSP?
Set-point error.
After a change in the
measuring range, the
controller set-point is outside
the selected range.
Readjust controller set-point.
*Al
*Al
Error limit value MAX
Error limit value MIN
After a change in the
measuring range, HI alarm
or LO alarm contacts are
outside the selected range.
Readjust alarm contacts.
Both Pt100 and positioner
feedback were selected.
(Cl2) invalid option selected
(pH, mV, F-).
Switch positions S1-3 and
S5 must match the built-in
option.
?
?
*OPTION?
51
ERROR MESSAGE
CAUSE
REMEDY
*RAM?
Hardware error in data
memory.
Must be repaired in W&T
factory.
*Pt 100?
Cable failure or short circuit
in a temperature sensor.
Check temperature sensor
and cable.
* COM?
Incorrect transmission of
data between amplifier, PC
control center and COM
interface card.
Time destroyed.
Value outside range.
Wrong format/time.
* System?
or
* ADU?
Loss of data in the
measuring amplifier.
The amplifier has to be
recalibrated by the
manufacturer if the error
remains after the system
has been "reset" as follows:
B-23.PCX - edition 01/1993
B-24.PCX - edition 01/1993
1. Pull amplifier out of basic
unit.
2. Set swichtes M1-6
(page 35) to position
ON.
3. Insert amplifier into basic
unit. "RAM" is displayed.
4. Press key "E".
5. Set swichtes S1-6 back
to position OFF.
6. Customer-specific settings,
e.g. alarm contacts, must
be restored afresh in the
P and F menus as above
proudure reverts the
amplifier to its basis
settings.
General note:
The modular design of the units makes it possible to interchange amplifiers,
electrodes, cables and impedance transformers of the same type so that any
source of error can be tracked down easily.
52
16.
INTEGRAL CONTROLLER (OPTION)
For the chlorine, pH and Redox analyzers the option "digital controller" is available. With
this option the following positioners can be controlled:
Electric positioner or regulating valve (three-step controller)
Motorized metering pumps, solenoid valves (pulse duration controller)
Solenoid metering pumps (pulse frequency controller)
Frequency converter, thyristor controller (continuous PID controller output)
The type of the positioner connected is selected by the software in the menu.
16.1
THREE-STEP CONTROLLER FOR SERVOMOTOR
The servomotor option of the integrated controller permits chlorine regulation in
conjunction with a servomotor as a positioning element. The servomotor determines the
chlorine dosage quantity as a function of control deviation, as is possible for instance
with chlorine gas systems V-761-GST and V-741-GST. The activation of servomotors
for control valves or for the stroke adjustments of dosing pumps is also possible.
The control direction is indicated by the two arrow LED’s in the display field (relay
activation).
The following controller parameters can be set with the three-step controller:
Ym (%)
Xp (%)
Ty (sec.)
Tn (sec.)
positioner feedback
proportional factor
positioner running time
integral action time
autom. adjustment (0...99%)
1...999 %
10...120 sec.
1...99.9 min.
The dynamic behaviour of the controller is adjustable via parameters Xp and Tn. This
permits the adaptation of the controller to different control loops.
In the "HAND" mode the servomotor can be operated with the arrow buttons OPEN
and CLOSE.
53
16.4
CONTROLLER WITH CONTINUOUS OUTPUT
This controller operating as a fixed value controller with continuous output calculates in
function of the measured value and the stored setpoint and the control parameters
an output current proportional to feedrate. The output current can be set to be 0...20
mA, 4...20 mA, 0...5 mA or 0...10 mA.
In the case of a control deviation of % the output current is 0, respectively 4 mA. For
higher deviations the output current is 5, 10 or 20 mA.
Typical positioners for this type of controller are metering pumps with current input,
thyristor control units with DC pumps or analog control valves.
The following parameters can be set with the continuous output controller:
Xp (%)
Ymin (%)
Ymax (%)
Tn (min.)
proportional factor
basic load
feedrate limit
integral action time
1...999 %
0...30 %
2...100 %
1...99.9 %
The dynamic response of the controller is adjustable via parameters Xp and Tn.
NOTE: Since each measuring amplifier has only one electrically isolated
current output, the current output for analog measured value
recording is not available in this mode.
In this case it is only possible to record the measured value via the
COM interface card.
The current output signal can be controlled with the direction keys in
the "HAND" mode. The display (arrow LED) of the direction of control
is not activated in this case.
57
16.5
CONTROL PARAMETERS AND THEIR INFLUENCE ON THE
CONTROL LOOP
Xp proportional factor
With the proportional factor the controller influence (gain) is affected by a control
deviation.
Gain = (1/Xp) x 100 %
For example, Xp = 100 % signifies that a control deviation of 10 % (measuring range
1.0 mg/l, setpoint 0.50 mg/l, actual value 0.40 mg/l) is amplified by the factor 1.
With the setting Xp = 50 % the same control deviation is amplified by the factor 2.
Effect:
The smaller the selection of the proportional factor Xp as a %, the greater
will be the amplification of the deviation from the setpoint and the faster the
attempt by the controller to correct the control deviation.
The gain can be changed within limits Xp = 1% (factor 100) to Xp = 999% (factor
0.1).
Tp operating cycle (only valid for metering pumps)
The operating cycle Tp defines a period in seconds which is to be adjusted to the type
of pump in question (see 12.3.2).
If an operating cycle of 30 sec. is selected, the pump starts every 30 sec. The running
time duration is dependent on the control deviation and the other set parameters. The
pump-on-time and pump-off-time always make the selected operating cycle Tp, in the
above example, 30 sec.
58
Ymax feedrate limitation (only applicable for metering pumps, solenoid pumps
or continuous positioners)
Ymax has been defined in conjunction with the metering pump activation as the
feedrate limitation.
With Ymax = 100 %, the feedrate factor Y is present at the controller output. With
a large control deviation the metering pump can run in continuous mode.
With Ymax = 30 %, the calculated feedrate factor Y is present at the controller
output, however only up to the limit of 30 % pump-on-time and 70 % pump-offtime. The control parameters correspond to an electronics dosing limit of the
positioning element.
Ymax can be set from 2 % to 100 %
Continuous output controllers:
If Ymax is set to 50 %, then the max. control signal (e.g. 20 mA)
half (10 mA).
is
limited
to
Ymin feedrate basic load (only applicable for metering pumps, solenoid pumps
or continuous positioners)
By means of this control parameter the following control elements
-
metering pump
solenoid pump
continuous controller
can be programmed for a basic load in the range of 0...30 %. The control element
will then regulate at least the basic load, independent of the controller.
If the controller requires more than the basic load the feedrate can be increased
up to Ymax limitation.
The menus Ymin and Ymax limit the feed range!
59
Control direction
In conjunction with the "Controller" option, the menu item "Control direction" is
interrogated in the P-menu. Available at the chlorine measuring amplifier are "Chlorine"
or "Dechlorination". Possible selections at the pH measuring amplifier are "Acid" and
"Alkaline".
This defines the activation behaviour of the output relay for the positioning element.
"Chlorine"
"Dechlorinate"
"Alkaline"
"Acid"
"Open"
"Close"
Control factor
the setpoint.
Control factor
the setpoint.
Control factor
the setpoint.
Control factor
the setpoint.
Control factor
the setpoint.
Control factor
the setpoint.
increases when the measured value is smaller than
decrease when the measured value is smaller than
increases when the measured value is smaller than
decrease when the measured value is smaller than
increases when the measured value is smaller than
decreases when the measured value is smaller than
Control deviation
The control deviation (Xd in %) represents the difference between setpoint and measured
value relative to the full range value.
Control deviation (Xd)
=
setpoint - measured value
full range value
Example:
setpoint:
measured value:
full range value:
0.40 mg/l
0.30 mg/l
2.00 mg/l
control deviation:
+ 5 %
61
x
100 %
17.
ADAPTATION OF THE CHLORINE AMPLIFIER
B-56.PCX - edition 01/1993
17.1
USE OF THE ADAPTATION
The adaptation is used for the automatic determination of the reaction times of the
control loop (dead time Tu and raise time Ts) respectively of the resulting controller
parameters Xp and Tn.
The adaptation menu is accessible by code number 900.
IMPORTANT NOTE!
The controller parameters determined by the adaptation must be considered as
recommended values for the initial start-up! In order to obtain the best control quality
the controller parameters Xp and Tn may be optimized manually.
62
17.2
PRECONDITIONS FOR THE ADAPTATION
-
Electric positioner or metering pump to be on automatic mode
Calibrated amplifier (zero and DPD value)
Dead time < 60 min.
Raise time < 480 min. (8 h) for 0...100 % feed range
Decomposition time of measured chlorine residual to 20 % of
measuring range < 480 min. (8 h)
Correct menu programme of:
measuring range (RGE mg/l)
direction of control (for example chlorine)
positioner (for example electric positioner)
positioner running time (Ty)
-
The adaptation should not be started at the following operating conditions:
when high doses of fresh water have been added
when the measuring cell is not yet run in
while the pool is cleaned
while filters are back-flushed
17.3
*
ADAPTATION MENUS
TEXT DISPLAY
DESCRIPTION
POSSIBLE SETTINGS
Code
Access to adaptation
menu
Access code for adaptation is 900
Chlor
Direction of control
Chlorination or dechlorination
El. Pos.
Control element
Electric positioner, metering pump,
solenoid pump or continuous
controller
* Ty (sec)
Control element
running time
10...180 sec.
Adapt
Adaptation
Automatic cycle for the
determination of Tu, Ts, Xp
and Tn
Tu (min)
Ts (min)
Dead time
Raise time
0.1 ... 60 min.
1 ... 480 min.
Only available when the control element is on electric positioner.
63
17.4
SEQUENCE OF THE ADAPTATION
By selecting code No. 900 in the code menu the menus for the adaptation are made
accessible. Instead of the standard P menus now the adaptation menus are displayed.
The adaptation is started in the menu "Adapt" by pressing key "E". Each phase of the
adaptation is displayed indicating the respective status, for example "Adapt 02". During
the sequence of the adaptation the following status conditions are displayed:
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
"Adapt
00"
01"
02"
03"
04"
05"
06"
07"
08"
09"
10"
11"
12"
13"
Activation
Chlorinator feedrate 0 % or metering pump OFF
Waiting period until measured value is < 0.2 of range
Chlorinator feedrate 100 % or metering pump ON
Waiting period until chlorinator at 100 %
Activation of dead time measurement
Measurement of dead time Tu
Plausibility interrogation of the dead time
Activation of the raise period measurement
Measurement of the raise period Ts
Calculation of control parameters
Chlorine feedrate 0 % or metering pump OFF
Waiting period until chlorinator 0 %
Switching over to mode AUTOMATIC
Depending on the type of positioner some of the status display may be skipped. Different periods are required to perform the individual steps. It is possible that some status
displays, due to the short period required for their performance, show up very shortly
or do not appear at all. The adaptation mode is also indicated via the COM-card.
NOTE!
Depending on the control loop the adaptation may require up to 13 hours. During
this period no substantial disturbing of the control loop should take place, such
as back-washing of filters or considerable variations in pool attendance.
64
17.5
ENDING THE ADAPTATION SEQUENCE
The adaptation sequence may be stopped at any time using the MAN/AUTO key. The
set parameters remain unchanged.
17.5.1
ENDING OF THE ADAPTATION WITHOUT ERROR
After the loop periods (dead time Tu and raise time Ts) have been determined without
an error, calculation of the control parameters Xp and Tn starts. This is indicated by
display "Adapt 10". The calculated parameters are marked off (Xp between 1...999
% and Tn between 0.1 ... 99.9 min.) and entered into the menu. Then the chlorinator
is run to 0 % or the metering pump is switched off (display "Adapt 12"). After the
adaptation has been completed the amplifier is switched to the AUTOMATIC mode.
The loop periods are entered into the menus "Tu (min)" and "Ts (min)" for control.
If a disturbance of the control loop takes place during the adaptation period, wrong
loop takes place during the adaptation period, wrong loop periods and consequently
wrong controller parameters may be determined.
NOTE!
Carrying out the adaptation does not influence the other control parameters Ymin, Ymax
and Tp. The parameters Xp and Tn are fixed for Ymin = 0 % (no basic load of the
metering pump) and Ymax (no feedrate limitation). If the plant should require a basic
load Ymin or a feedrate limitation Ymax, it must be noted that this will limit the control
range. This involves the risk of overchlorination (Ymin too high) or underchlorination
(Ymax too much limited). The controller parameter Tp must always be adapted to the
metering pump used:
Pump strokes/min.
Tp value
<=20
20-40
40-80
80-125
125-200
120
100
60
30
15
65
17.5.2
ENDING OF THE ADAPTATION WITH ERROR
In case there are serious disturbances of the control loop during the adaptation period,
for example filter back-washing, or if the control loop is too long, the adaptation process
is stopped.
Possible error conditions:
-
Starting value not reached
After activation of the adaptation and running the chlorinator to zero or switching
off the dosing pump, the amplifier waits until the measured value has
dropped below the starting value (0.2 * of range). This waiting period is displayed
as "Adapt 02" and must not exceed 8 hours.
-
Dead time too big
The period of time measured between the feedrate increase of the chlorinator
respectively starting of the dosing pump and the rise of the measured value must
not exceed one hour. This time measurement is displayed as "Adapt 06".
-
Raise time too big
The period of time required for increasing the measured value to 50 % of the
range while the chlorinator or dosing pump are operating at 100 % capacity must
not exceed 4 hours. This time measurement is displayed as "Adapt 09".
If any of the above error conditions occurs, the adaptation is stopped. The amplifier is
switched to the DEFAULT AUTOMATIC mode (display DFT mg/l). In this mode the
amplifier reacts as in the AUTOMATIC mode, but uses the control parameters set prior
to the adaptation process. This condition is also indicated via the COM-card.
The DEFAULT AUTOMATIC mode can be stopped by pressing the "MAN/AUTO" key.
Then the amplifier is in the MANUAL mode.
66
17.6
DETERMINATION OF THE CONTROLLER PARAMETERS USING
Tu AND Ts
If the loop periods Tu and Ts are already known or if it is impossible to determine
them automatically, the manually measured loop periods may be entered into the menus
"Tu (min)" and "Ts (min)". When starting Tu and Ts also the parameters Xp and Tn
are calculated and entered into the menus. After this operation the amplifier is not
switched automatically to the AUTOMATIC mode.
NOTE!
By storing Tu and Ts respectively the calculated values Xp and Tn the remaining
parameters Ymin, Ymax and Tp are not influenced. The parameters Xp and Tn are
fixed for Ymin = 0 % (no basic load of the dosing pump) and Ymax (no feedrate
limitation). If the plan should require a basic load Ymin or a feedrate limitation Ymax,
it must be noted that this will limit the control range. This involves the risk of
overchlorination (Ymin too high) or underchlorination (Ymax too much limited).
The controller parameter Tp must always be adapted to the dosing pump used:
Pump strokes/min.
Tp value
<=20
20-40
40-80
80-125
125-200
120
100
60
30
15
67
18.
COM INTERFACE CARD
Measuring amplifiers of the DEPOLOX 4 serie may be related to RS485-PROWAY via
interface card COM485. Placing of the interface card is possible in every box of the DEPOLOX
4. It is used as an interface for 1 to 3 amplifiers.
These are:
-
Test amplifiers for chlorine, chlorine dioxyde and ozone
Test amplifier for pH measuring
Test amplifier for redox measuring
Test amplifier for conductivity measuring
Test amplifier for fluoride measuring
Test amplifier for temparature measuring
Process data like
- actual feed back value
- measuring range
- unit of the measured value
- parameters of the set points (value, hysteresis, and deceleration)
- set point
- measured value of the option (i.e. temparature or reply of the regulator)
- operation state of the amplifier
- error message and alarm message
may be printed or further operated with CMS. Set point and parameters of the limit may be
changed centrally with the CMS.
Detailed information is given in the instruction manual BA-40014 E for the interface card
COM485.
19.
SERVICING AND REPAIR
The WALLACE & TIERNAN GmbH service department is continuously at your service
for installation, commissioning, servicing and repairs. We recommend that you conclude
an appropriate sevice contract with us.
68
20.
TECHNICAL DATA
20.1
DEPOLOX 4 MEASURING CELL
Measuring cell:
potentiostatic 3 electrode cell
Accuracy:
0.01 mg/l ± 1 digit
(2 % of full scale value)
Sensitivity:
0.01 mg/l
(1 % of full scale value)
Repeatability:
0.01 mg/l ± 1 digit
(2 % of full scale value)
Stability:
± 2 % of full scale value for the period of
one month under favourable conditions
Response time:
90 % of the change of the Cl2 residual within
60 sec. of the entry of the sample water into
the measuring cell
Output signal:
µA current
Dimensions:
260 W x 350 H x 160 D (mm)
Weight:
3.8 kg
Material:
ABS, PVC, Plexiglass
Temperature range:
0...50°C for the sample water
20.2
BASIC UNIT FOR WALL MOUNTING
Dimensions:
337 W x 223 H x 228 D (mm)
Weight:
2.8 kg
Type of protection:
IP 65
Terminal compartment
connection:
1x PG16; 3x PG13; 4x PG11; 3x PG9; 3x PG7
Enclosure:
plastic, ABS, light grey/dark grey,
hinged front with cylinder lock
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20.3
CHLORINE RESIDUAL AMPLIFIER
Measuring range:
0 ... 500 ppb / 0 .... 1.0 / 0 ... 2.0
0 ... 5.0 / 0 ... 9,99 mg/l
Current inputs:
- 5 ... 200 µA
Current output:
0 ... 20 / 4 ... 20 / 0 ... 10 / 0 ... 5 mA
volt-free (500 V to earth)
Load voltage 10 V
Accuracy 0.2 % referred to full scale value
Temperature drift 0.1 % / 10°C
Ambient temperature:
0 ... 50°C
Temperature compensation:
optional with PT100 sensor (0 ... 50°C)
Relay outputs:
2 changeover contacts 250V/1A,
volt-free limit contacts
2 relay outputs 250V/1A for electric positioner
or metering pump activation
Power consumption:
max. 10 VA
Power supply:
230V ± 15 % / 115V ± 15 %
50/60Hz
Dimensions:
width:
height:
depth:
Weight:
775 g
70
15 TE (76 mm)
3 TE (129 mm)
160 mm
20.4
pH MEASURING AMPLIFIER
Measuring range:
pH 0 ... pH 14
stepless adjustable bottom value
pH 0 ... pH 5
stepless adjustable top value
pH 9 ... pH 14
Current output:
0 ... 20 / 4 ... 20 / 0 ... 10 / 0 ... 5 mA
volt-free (500 V to earth)
Load voltage 10 V
Prescision 0.2 % referred to full scale value
Temperature drift 0.1 % / 10°C
Ambient temperature:
0 ... 50°C
Temperature compensation:
optional internal (0...99°C) or
external compensation using Pt 100 sensor
(0...50°C)
Relay outputs:
2 changeover contacts 250V/1A,
volt-free limit contacts
2 relay outputs 250V/1A for servomotor
or metering pump activation
Power consumption:
max. 10 VA
Power supply:
230V ± 15 % / 115V ± 15 %
50/60Hz
Dimensions:
width:
height:
depth:
Weight:
775 g
71
15 TE (76 mm)
3 TE (129 mm)
160 mm
20.5
REDOX MEASURING AMPLIFIER
Measuring range:
0 mV ... +999 mV
stepless adjustable range, min.
300mV between bottom and top value
Current output:
0 ... 20 / 4 ... 20 / 0 ... 10 / 0 ... 5 mA
volt-free (500 V to earth)
Load voltage 10 V
Prescision 0.2 % referred to full scale value
Temperature drift 0.1 % / 10°C
Ambient temperature:
0 ... 50°C
Relay outputs:
2 changeover contacts 250V/1A,
volt-free limit contacts
2 relay outputs 250V/1A for servomotor
or dosing pump activation
Power consumption:
max. 10 VA
Power supply:
230V ± 15 % / 115V ± 15 %
50/60Hz
Dimensions:
width:
height:
depth:
Weight:
775 g
72
15 TE (76 mm)
3 TE (129 mm)
160 mm