DO 9505
INSTRUCTIONS MANUAL
DO 9505
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DO 9505 pH-METER - THERMOMETER - DATA-LOGGER
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DO 9505
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Input A, BNC female connector
Double LCD display
The symbol indicates that the HOLD key has been pressed
Battery symbol
The display shows the mean value
The display shows the relative value
Depending on the function chosen, the symbol indicates that the serial output function is
switched on (flashing symbol) or that the instrument is storing (symbol permanently lit)
HOLD key for blocking the reading
Key for taking relative measurements
Key for selecting the various programs
Key for selecting the serial output function
When enabled, the key increases the values shown on the display; in program P1 it activates
the function for erasing data from the memory
Key for selecting pH or mV measurement
Output for RS-232C (SUB D male 9-pole)
Input B, female 8-Pole connector DIN 41524
The measurement shown on the upper display (for input A) is in pH
The measurement shown on the upper display (for input A) is in mV
The temperature measurement shown on the lower display is in °C
The temperature measurement shown on the lower display is in °F
The display shows the maximum value
The display shows the minimum value
When lit, the symbol indicates that it is possible to activate the function for calibration of the
pH electrode or for changing the manual compensation temperature
Key for switching the instrument on and off
When pressed in sequence the display indicates the MAX, MIN and MEAN value, normal
display
Key for activating the function for calibrating the pH electrode or for changing the manual
compensation temperature
When enabled, the key decreases the value shown on the display, starts, stops and resets
the RCD function
The key has various functions: it starts and stops storage, or confirms the set parameters
The key selects temperature measurement in °C or °F
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KEY
+
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
All the symbols are lit for a few
seconds after pressing the
ON/OFF key.
Complete display.
ON/OFF key. Press this key
repeatedly to switch the instrument on or off.
The instrument has a cut-out
system (Auto Power Off) which
switches off automatically after
about 8 minutes.
H
The symbol flashes to indicate
that Auto Power Off is disabled
HOLD key. If this key is pressed
together with the ON/OFF key
while switching on, for the duration of the switching-on routine,
the self cut-out function (Auto
Power Off) is disactivated.
The symbol flashes at a frequency of 1 Hz.
The instrument can be switched
off only by pressing the ON/OFF
key.
H
HOLD
When this key is pressed during
normal operation the value shown
on the display is frozen and the
HOLD symbol lights up.
When the key is pressed for the
second time the instrument
returns to normal operation and
the HOLD symbol goes off.
pH
°C
g
REL
65
m3
The REL (Relative) key allows
you to display or store relative
values or send them immediately
onto the serial line. The values for
comparison are stored at the precise moment in which the key is
pressed.
Data may be stored when the
REL button is active.
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
When unloading relative data
(REL function active) immediately
onto the serial line, at the end of
the data a report will be provided
giving the maximum, minimum
and mean relative values and the
reference values on which the calculation of the relative values was
based.
pH
pH
°C
pH
°C
MAX
DATA CALL key (Max - Med Min). When DATA CALL is pressed repeatedly the max, min and
mean pH or mV values are shown
on the top part of the display, the
temperature values on the bottom
part of the display.
°C
MIN
MED
Programming of the instrument is
activated by pressing the PROG
key.
The message P0 appears at the
top of the display indicating that
the parameter P0 is being programmed.
By continuing to press the PROG
key the messages P1, P2, P3, P4,
P5, P6, P7, P8, P9, P10, P11, P0,
etc. are displayed.
Press the ENTER key on one of
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
the points just described to activate programming of the desired
parameter.
- P0 When ENTER is pressed with P0
on the display, the instrument
returns to normal operating mode
without storing any parameter.
P0+
P1+
= data dump
P1+
= erase memory
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- P1 When ENTER is pressed with P1
on the display, the data stored in
the memory of the instrument are
unloaded.
The message dUP appears on
the upper display of the instrument and the number of the
memory unit currently being dumped appears on the lower display.
At the end the instrument automatically returns to normal operating
mode.
s
When the
key, MEMORY
CLEAR sub-command, is pressed
with CLr on the display, all the
stored data are erased.
After they have been erased, the
instrument will display the number
of memory units erased.
At the end the instrument automatically returns to normal operating
mode.
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
P2+
storage
= interval
programming
hours minutes
DESCRIPTION
- P2 When ENTER is pressed with P2
on the display, the storage time
parameter may be modified.
This parameter is used for the following two functions:
1. Logging time, or time elapsing
between two consecutive data
storages in the memory.
2. Data dump interval, or time elapsing between two immediate
data dumps on the serial line.
s
seconds
t
The and keys are used to
define the desired interval time.
At bottom right of the display the
instrument indicates the seconds
(1 - 59).
At top right of the display the
instrument indicates the minutes
(1 - 59).
At top left of the display the instrument indicates the hours (1 - 12).
After defining the time, press
ENTER to return to normal operation, or press the PROG key to
move on to step P3.
In the storage function the instrument is able to store more than
30,000 acquisitions made at the
set interval.
The time taken to fill the memory
completely is a function of the
recording interval and may be
obtained from the following table:
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
RECORDING INTERVAL
TIME TO FILL THE MEMORY
1 sec
1 min
1 hour
8 hours
20 days
1250 days
Once the memory has been filled
the instrument automatically stops
and leaves storage status.
The flashing FUL message
appears.
The instrument switches off after
8 minutes.
P3+
= set Baud Rate
- P3 When ENTER is pressed with P3
on the display, the Baud Rate of
the RS-232C serial transmission
may be modified.
The and keys are used to
select the desired value.
The possible values are:
19.2 = 19200 Baud
9.6 = 9600 Baud
4.8 = 4800 Baud
2.4 = 2400 Baud
1.2 = 1200 Baud
0.6 = 600 Baud
0.3 = 300 Baud
Finally press ENTER to return to
normal operation, or press the
PROG key to move on to step P4.
s
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
P4+
= set year
DESCRIPTION
- P4 When ENTER is pressed with P4
on the display, the year value may
be set or changed.
The and keys are used to
select the desired year.
Then press PROG to move on to
step P5 (the ENTER key is not
active).
s
P5+
= set month
- P5 When ENTER is pressed with P5
on the display, the month may be
set or changed.
The and keys are used to
select the desired month.
Then press PROG to move on to
step P6 (the ENTER key is not
active).
s
P6+
t
t
- P6 When ENTER is pressed with P6
on the display, the day may be set
or changed.
The and keys are used to
select the desired day.
Then press PROG to move on to
step P7 (the ENTER key is not
active).
= set day
s
70
t
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
P7+
= set hours
DESCRIPTION
- P7 When ENTER is pressed with P7
on the display, the hour may be
set or changed.
The and keys are used to
select the desired hour.
Then press PROG to move on to
step P8 (the ENTER key is not
active).
s
P8+
= set minutes
- P8 When ENTER is pressed with P8
on the display, the minutes may
be set or changed.
The and keys are used to
select the desired minutes.
Then press ENTER to return to
normal operating mode or PROG
to move on to step P9, without
updating the internal clock.
Quitting with the ENTER key
updates the internal clock with the
date and time just set, setting the
seconds at zero at the time of
quitting.
s
P9+
= enable/disable
self cut-out
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t
t
- P9 When ENTER is pressed with P9
on the display, the instrument
enters the program which enables
or disables the self cut-out function when it is in storage mode
and with a set storage interval
higher than or equal to 1 minute.
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
s
t
The and keys are used to
select the value 00 or 01.
00 With a set storage interval
lower than 1 minute, the
instrument does not switch off
automatically; it remains
always lit.
When the ON/OFF key is
pressed, storage stops and
the instrument switches off.
00 With a set storage interval
higher than 1 minute, the
display switches off automatically after about 8 minutes. At
each set storage interval there
is a beep and the display switches on for a few seconds.
The display can be switched
on or off by pressing the
ON/OFF key. The instrument
keeps on storing if you keep it
switched on.
The display switches off automatically after about 8 minutes.
To stop storage, press the
ON/OFF key (if the instrument
is off). Press the ENTER key.
01 With a set storage interval
lower than 1 minute, the
instrument does not switch off
automatically.
When the ON/OFF key is
pressed, storage is interrupted
and the instrument switches
off.
01 With a set storage interval
higher than 1 minute, the
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
display does not switch off
automatically; it remains
always lit and goes on storing.
When the ON/OFF key is
pressed the display stops till
the next acquisition. Then it
switches on again and
remains lit.
To stop storage, press the
ENTER key.
The ENTER key is used to return
to normal operating mode, while
pressing the PROG key moves on
to step P10.
P10+
voltage
= calibration
of input A
mV
P11+
calibrate
= temperature
probe in input B
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- P10 When ENTER is pressed with
P10 on the display, the instrument
enters the program for calibrating
the voltage of input A and the
message CAL appears at the bottom of the display.
Pressing the PROG key moves
on to step P11.
The calibration instructions are
described on page 87.
- P11 When ENTER is pressed with
P11 on the display, the program
for calibrating the temperature
probe inserted in input B is activated (series TP 870 or direct 4-wire
Pt100 probe).
In the program for calibrating the
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
°C
pH
°C
g
Serial
Out
Memory
m3
DESCRIPTION
temperature probe inserted in
input B, the instrument shows the
temperature of the probe inserted
in input B at the top of the display
and the message CAL at the bottom of the display.
The calibration instructions are
described on page 88.
SERIAL OUTPUT key. The
SERIAL OUTPUT key sends the
data being acquired onto the
serial line immediately, according
to the set programming parameters.
NOTE: the choice of the Baud
Rate influences the speed at which the data are sent onto the
serial line.
With a data transmission speed of
300 Baud (the character being
composed of 10 bit: 1 start bit +8
character bit +1 stop bit), the time
taken to send 80 characters on
the serial line is: 80/(300/10) =
2.7 sec.
There is therefore a limit on the
minimum time that may be set as a
function of the Baud Rate chosen:
BAUD
RATE
300 Baud
600 Baud
> 600 Baud
74
MINIMUM
SETTABLE
TIME
4 sec.
2 sec.
1 sec.
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
If a time of less than 4 sec. with a
speed of 300 Baud is accidentally
set during programming, the time
is automatically corrected to 4
sec. The Serial Out/Memory symbol flashes during the immediate
unloading of data onto the serial
line. The instrument does not
switch off automatically.
The functions of all the keys are
disabled, preventing the performance of all their functions except
the SERIAL OUTPUT key and the
ON/OFF key.
When pressed again, the SERIAL
OUTPUT key ends the unloading
of data in progress. A report is
issued stating the maximum, minimum and mean values.
t
RCD
pH
°C
75
DOWN
(RCD sub-function).
During programming this key is
used to decrease the value of the
parameter being considered.
In normal mode the RCD subfunction calculates and stores the
maximum, minimum and mean
values.
When pressed repeatedly the
/RCD key starts and stops the
Record function for calculating the
max., min. and mean values.
When the /RCD key is held
down the instrument emits a short
beep followed by a long one. This
confirms that the max., min. and
mean values stored previously
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t
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
have been erased from the
memory and a new series of
recordings is started which will be
used as the basis on which to calculate and store new max., min.
and mean values.
After resetting of the max., min.
and mean values, the RCD function has a duration of about
30,000 readings, that is 4 hours.
At the end, the RCD function is
automatically interrupted and the
max. min. and mean values calculated up till then are maintained.
During /RCD mode the Auto
Power Off function is disabled and
the symbol flashes at a frequency of 2 Hz.
ATTENTION:
If the symbol does not flash at
a frequency of 2 Hz when the
RCD key is pressed it means that
the RCD function has stored more
than 30,000 readings and cannot
continue any longer.
t
H
H
pH
°C
CAL
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CAL key. The key allows access
to the functions for calibrating the
pH electrode and for changing the
compensation temperature which
may be set manually.
See the instructions for use on
page 86.
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
s key. During programming this
key is used to increase the value
of the parameter being considered.
During programming, if the key
is pressed in function P1, all data
present in the memory are erase
(Memory Clear).
s
pH
°C
pH
°F
°C/°F key. When this key is pressed alternately the temperature
received from probe B is shown at
the bottom of the display in
degrees °C or degrees °F.
If the temperature probe is not
connected to the instrument, the
manually set compensation temperature is displayed.
The key is active in RCD, REL,
DATA CALL and HOLD status.
ENTER key (Start-Stop sub-function). During programming this
key is used both to enter programming and to confirm the
value of the parameter considered.
In normal mode the ENTER key
as Start-Stop sub-function is used
alternatively to start or stop storage of a new block of data to be
kept in the memory of the instrument.
Data storage is performed at the
rate set during programming of
step P2.
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
DESCRIPTION
The data stored between one
start and the following stop form a
block.
Different blocks can thus be formed, all ending (during unloading)
with the report giving the maximum, minimum and mean values.
The Serial Out/Memory symbol
remains lit for the whole period.
The Auto Power Off function is
active and the instrument switches itself off after about 8 minutes of inactivity.
It is restarted automatically by the
clock interrupt control which reactivates the instrument for only the
time needed for all the acquisition
and storage operations.
Once this has been done the
instrument switches itself off
again.
During this phase the instrument
is apparently off, but it is active in
operative mode.
If the Serial Out/Memory symbol
lights up when switching on the
instrument with the ON/OFF key,
this means that the instrument
was in storage status.
In this stage the SERIAL
OUTPUT and PROG keys are not
enabled. When this operative
mode is disactivated the Serial
Out/Memory symbol is not lit.
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KEY
SYMBOLS LIT BESIDES
THE NUMBERS
pH
°C
pH
mV
°C
DESCRIPTION
pH/mV key. When this key is
pressed alternately the pH or mV
value received from the probe
inserted in input A is shown at the
top of the display(when measuring the redox potential ORP or
measuring with a specific ion
electrode).
°F
The key is active in RCD, REL,
DATA CALL and HOLD status.
79
80
Ag/AgCI
0 - 100°C
BNC
GK 90
CP
BNC
Ag/AgCI
0 + 100°C
GK 80
Ag/AgCI
0 + 100°C
GK 60
Ag/AgCI
Ag/AgCI
0 + 80°C
GK 30
0 + 100°C
Ag/AgCI
0 + 80°C
GK 20
GK 70
Internal
reference
Working
temperature
No. Cod.
Glass
Glass
Glass
Glass
Epoxy
Epoxy
Body
Liquid
Liquid
Liquid
Liquid
Gel
Gel
Reference
S7
S7
S7
S7
S7
Drawing
S7
Extension cable
Redox - platinum
Meat - Fish
Micro version for laboratory
Dairy products - Jelly solutions
General uses - agriculture
General uses - agriculture
Application fields
pH Combined electrodes - Glass/epoxy body - KCI electrolyte saturation + AgCI
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PROBE CONNECTION
A BNC female connector at input A allows the connection of electrodes for measuring pH, electrodes for measuring the redox potential (ORP) and specific ion electrodes (ISE).
In each case the signal supplied is a voltage.
As the internal impedance of the electrodes (especially pH and specific ion) is very high (50÷200
Mohm), care must be taken to ensure that the connectors are clean. If no electrode is connected to
the BNC connector, it must be closed with the plastic cap provided. Electrodes with special couplings may be connected to the instrument using adapter extension cables.
At input B an 8-pole female connector DIN 41524 allows series TP 870 temperature probes or 4wire Pt100 probes to be connected to the instrument.
These probes may be used for measuring temperature or for the automatic compensation of the
temperature coefficient with the electrode in pH measurement (Nernst coefficient).
A Pt100 temperature sensor is used in series TP 870 probes. In the connector (8-pole male connector DIN 41524) there is a printed circuit which amplifies and linearizes the low impedance signal
provided (2.375 mV/°C). Since each probe is calibrated individually at 0°C and 100°C a good interchangeability of probes is obtained.
Connection of a 4 wire Pt100 probe or TP 870 series in the input B.
Probe Pt100
6
1
4
8
Probe TP 870 series
7
3
5
6
1
4
8
2
2 3
Passive probe
Pt100 4 wire
DO 9505
7
7
3
5
3
7
6
6
8
5
2
4 5
Pt100
Instrument
Input for probes
Pt100 or
TP 870 series
1
4
2
1
8
5 4
+Vcc GND OUT -Vcc
2.375 mV/°C
Active probe Pt100
TP 870 series
81
3 2
8
1
6
7
Pt100
-Vcc OUT GND +Vcc
2.375 mV/°C
Probe Pt100
Probe TP 870 series
82
Air probe
Immersion probe
TP 870/A
TP 871
Description
*
*
*
*
*
B) Time constant observed with metal surface at 200°C
∅ 3 x 70 mm
∅ 4 x 230 mm
∅ 4 x 230 mm
∅ 4 x 150 mm
∅ 3 x 230 mm
Note: The time constant is the time needed to respond to 63% of the temperature changes.
A) Time constant in water at 100°C
Surface probe
Penetration probe
TP 870/P
TP 870/C
Immersion probe
TP 870
No. Cod.
TEMPERATURE PROBES
Drawing
*
C) Time constant in air at 100°C
3”
A
3”
B
12"
C
3”
A
3”
A
Sec.
- 60
+ 200
- 60
+ 300
- 60
+ 300
- 60
+ 400
- 60
+ 400
Temp
°C
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HOW TO MEASURE
1. Press the ON/OFF key to switch on the instrument.
* This operation enables the automatic cutout timer (Auto Power Off).
* If you wish power supply without automatic interruption, press the HOLD and ON/OFF keys
simultaneously when switching the instrument on; the HOLD key must be held down for the
duration of the switching-on routine. In this case the symbol flashes at a frequency of 1 Hz.
2. Check display.
* After all the segments are lit, the measured pH value (indicated by the pH symbol) is shown
at the top of the LCD display and the temperature value (indicated by the °C symbol) at the
bottom.
* If there is no electrode connected to the BNC connector (input A) or if it is faulty or badly connected, the measurement fluctuates and the Err signal appears. In this case the electrode part
or the connector must be checked.
* If the electrode connected to the BNC connector is not immersed in a solution or is not a pH
electrode, immerse it in the measuring liquid or select the correct measuring unit mV if it is a
specific ion electrode or an electrode for measuring redox potential.
3. Selecting the measuring unit (pH/mV or °C/°F).
* After the instrument has been switched on the measuring unit can be chosen. The pH or mV
unit may be chosen by pressing the pH/mV key alternately. The symbol appears on the display.
* Temperature measurements in °C or °F may be chosen by pressing the °C/°F key alternately.
The symbol appears on the display.
* If the temperature probe is not connected the value set for manual temperature compensation
appears.
4. The instrument is switched off by pressing the ON/OFF key.
* Because of the Auto Power Off function the instrument may switch itself off during measurements. In this case press the ON/OFF key to switch it on again.
5. Memory DUMP Function.
The DUMP function allows unloading of the data stored in the internal memory of the instrument.
The total memory capacity available is 512 Kbyte, with the possibility of storing more than 30,000
recordings. Access to this function is obtained by launching program P1 on the display and pressing the ENTER key. In this way the data are unloaded onto the serial line and the message dUP
appears at the top of the display throughout the duration of the Dumping process while the number of the memory unit currently being dumped appears at the bottom.
The data are transferred directly on the serial line through the CP 232 C adapter cable.
During this phase the instrument does not switch itself off (Auto Power Off is disabled). When the
ENTER key is pressed, data unloading is stopped for a moment. When the ENTER key is pressed again, data unloading is resumed.
By using the Xon/Xoff protocol it is possible to unload the data on a computer for the control of
data flow:
H
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- the Xoff character (hex 13) on the serial port stops the current unloading of data
- the Xon character (hex 11) reactivates the current unloading of data which was interrupted.
When the PROG key is pressed, data dumping is concluded.
At the end of each block a report is issued giving the maximum, minimum and mean values calculated on the block.
At the end of Dumping the instrument returns to normal function.
During the DUMP phase the instrument does not switch off automatically, all the key functions
are disabled except the ENTER key and the ON/OFF key.
NOTES: The block is defined at the time of storage as a group of consecutive recordings. The
first interruption in storage ends and determines the block.
6. Various operations.
* For operations such as HOLD, REL, DATA CALL, PROG, SERIAL OUTPUT, RCD, CAL and
ENTER, see the specific functions described in the text.
* The instrument usually switches off automatically after 8 minutes of inactivity, with the following
few exceptions:
a) Instrument in RCD status.
b) Instrument in Auto Power Off Disabled status.
In these two cases the instrument switches off only when the ON/OFF key is pressed.
c) Instrument during unloading of stored data.
d) Instrument during SERIAL OUTPUT of immediate data.
e) Instrument in storage function.
The instrument switches off automatically 8 minutes after the low battery warning and interrupts
storage. When it switches on again there are two possibilities:
1. If the battery is definitively low, even when the instrument switches on again LOU appears
on the display together with the battery symbol.
The PROG key (P1+ENTER) enables the activation of the unloading of stored data even when
the battery is low.
2. If the battery has had time to recover and when the instrument switches on its charge
seems, even just a little, higher than the minimum value, LOU appears on the display without
the symbol for a short period of time (about 4 seconds), after which the instrument returns
to normal operation; this is to remind the user that the instrument was previously in storage
function and that this procedure was interrupted by the low battery warning.
H
ATTENTION:
The use of the keys is relatively simple, but care must be taken to avoid setting it by mistake in an
undesired mode. Ensure that HOLD, RCD, REL, MAX, MIN, MED, Serial Out/Memory are not
displayed during normal operation.
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CALIBRATING THE INSTRUMENT WITH A pH ELECTRODE
t
t
With the CAL key and the and keys it is possible to calibrate any pH electrode with the instrument DO 9505. Calibration may be automatic or manual.
A) AUTOMATIC CALIBRATION
Any kind of pH electrode may be adapted for the instrument by calibrating it. This is possible with
pH 4.01, pH 6.86 and pH 9.18 buffer solutions.
Calibrating offset. 1st calibration
1. Connect a pH electrode to input A. Remove the protection cap at the end of the electrode and
immerse the electrode in a pH 6.86 buffer solution. Immerse the temperature probe connected
to input B of the same instrument (automatic temperature compensation).
2. Stir the electrode for a few seconds until a stable pH value is achieved. Press the CAL key. The
CAL symbol appears, indicating the calibration phase has begun. Press the pH/mV key. The
instrument shows the pH value of the buffer solution at the top of the display, the pH symbol flashes. The automatic compensation temperature value appears at the bottom.
3. Press the CAL key to confirm the pH value and to confirm the first calibration point. The pH symbol stops flashing. The CAL symbol disappears.
Calibrating gain or slope. 2nd calibration
1. Remove the electrode and the temperature probe from the pH 6.86 buffer solution and wash
them accurately with running water. Dry with absorbent paper without rubbing the pH electrode
so as not to create an electrostatic load.
2. Immerse the electrode and the temperature probe in a pH 4.01 or pH 9.18 buffer solution (whichever of the two is nearer to the value of the solution to be analysed). Stir the electrode for a
few seconds until the measurement on the display is stable. Press the CAL key. The CAL symbol appears, indicating the calibration phase has begun. Press the pH/mV key. The instrument
shows the pH value of the buffer solution at the top of the display, the pH symbol flashes. The
automatic compensation temperature value appears at the bottom.
3. Press the CAL key to confirm the pH value and to confirm the second calibration point. The pH
symbol stops flashing. The CAL symbol disappears.
4. Remove the electrode and the temperature probe from the buffer solution and wash them accurately with running water.
At this point calibration is complete and the electrode is ready for use.
The instrument stores the calibration pH and temperature values and the date of calibration of the
electrode. These values are printed in the various reports supplied by the instrument.
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NOTE: The instrument is programmed to recognize three buffer solutions: pH 6.86, pH 4.01 and pH
9.18. If the error signal E3 or E4 appears during the calibration phases, E3 means that the
slope of the line pH/mV set for the two buffer solutions is 20% lower than the rated value;
E4 means that the slope of the line pH/mV set for the two buffer solutions is 150% higher
than the rated value.
B) MANUAL CALIBRATION
Manual calibration of the DO 9505 with any pH electrode may be carried out with any buffer solution. To calibrate, proceed as follows:
Calibrating offset. 1st calibration (buffer solution close to pH 7.00)
1. Connect a pH electrode to input A. Remove the protection cap at the end of the electrode and
immerse the electrode in the buffer solution. Immerse the temperature probe connected to input
B of the same instrument (automatic temperature compensation).
2. Stir the electrode for a few seconds until a stable pH value is achieved. Press the CAL key. The
CAL symbol appears, indicating the calibration phase has begun. Press the pH/mV key. The
instrument shows the pH value of the buffer solution at the top of the display, the pH symbol flashes. The automatic compensation temperature value appears at the bottom.
3. Using the and keys, correct the value shown on the display until it coincides with the value
of the buffer solution used.
4. Press the CAL key to confirm the pH value and to confirm the first calibration point. The pH symbol stops flashing. The CAL symbol disappears.
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Calibrating gain or slope. 2nd calibration (acid or basic buffer solution, depending on the
measurement to be made)
1. Remove the electrode and the temperature probe from the buffer solution used previously and
wash the electrode and the probe accurately with running water. Dry with absorbent paper
without rubbing the pH electrode so as not to create an electrostatic load.
2. Immerse the electrode and the temperature probe in the new buffer solution. Stir the electrode
for a few seconds until the measurement on the display is stable. Press the CAL key. The CAL
symbol appears, indicating the calibration phase has begun. Press the pH/mV key. The instrument shows the pH value of the buffer solution at the top of the display, the pH symbol flashes.
The automatic compensation temperature value appears at the bottom.
3. Using the and keys, correct the value shown on the display until it coincides with the value
of the buffer solution used.
4. Press the CAL key to confirm the pH value and to confirm the second calibration point. The pH
symbol stops flashing. The CAL symbol disappears.
5. Remove the electrode and the temperature probe from the buffer solution and wash them accurately with running water.
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At this point calibration is complete and the electrode is ready for use.
The instrument stores the calibration pH and temperature values and the date of calibration of the
electrode. These values are printed in the various reports supplied by the instrument.
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C) MANUAL TEMPERATURE SETTING
The pH measurement is influenced by temperature. If during calibration the temperature probe is
not available or is broken, temperature is set by hand.
If there is no probe this temperature remains fixed on the display. To set it, proceed as follows:
1. Press the ON/OFF key to switch on the instrument.
2. Press the CAL key. The CAL symbol appears. Press the °C/°F key. The °C or °F symbol flashes
(depending on the unit chosen).
3. Use the and keys to set the temperature value corresponding to the temperature of the
liquid that is to be measured.
4. Press the CAL key to confirm the set value. The °C or °F symbol stops flashing and the CAL
symbol disappears
NOTE: This value will remain stored in the instrument until it is changed.
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INSTRUCTIONS ON CALIBRATING THE INSTRUMENT FOR VOLTAGE
(INPUT A) AND TEMPERATURE (INPUT B) FOR TP 870 and 4-WIRE Pt100
VOLTAGE CALIBRATION INPUT A
In program P10, when ENTER is pressed the instrument enters the procedure for calibrating the
voltage of input A; the voltage value measured at the input is shown at the top of the display and
the message CAL at the bottom.
Instrument calibration comprises compensation of the offset (with the first calibration point) and
of the amplification of the instrument (with the second calibration point).
First calibration point 0.0 mV
With the voltage simulator inserted in input A, simulate a voltage of 0.0 mV.
Wait for the instrument measurement to become stable.
Press the CAL button, the mV symbol will flash and the instrument will propose the calibration voltage of 0.0 mV.
Press the CAL button, the mV symbol will stop flashing and the instrument will gradually go to
the calibration value of 0.0 mV.
Second calibration point 480 mV
With the voltage simulator inserted in input A, simulate a voltage of 480 mV.
Wait for the instrument measurement to become stable.
Press the CAL button, the mV symbol will flash and the instrument will propose the calibration voltage of 480 mV.
Press the CAL button again, the mV symbol will stop flashing, the CAL symbol will disappear
from the bottom of the display and the instrument will return to normal operation, leaving the
calibration process, and will gradually go to the calibration value of 480 mV.
After the second calibration point the procedure is complete and the instrument updates the calibration date, stated in the reports.
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TEMPERATURE CALIBRATION INPUT B WITH THE TP 870 PROBE
In program P11, when ENTER is pressed the instrument enters the procedure for calibrating input
B for the TP 870 or 4-wire Pt100 probe.
Before entering program P11, insert the simulator or the probe with which calibration is to be
performed.
The instrument shows the temperature value measured at input B at the bottom of the display and
the message CAL at the top.
Instrument calibration comprises compensation of the offset (with the first calibration point) and
of the amplification of the instrument (with the second calibration point).
First calibration point 0.0°C (or 32.0°F)
With the Pt100 simulator inserted in input B, simulate a temperature of 0.0°C (32.0°F).
Wait for the instrument measurement to become stable.
Press the CAL button, the °C symbol (or the °F symbol) will flash and the instrument will propose the calibration temperature of 0.0°C (or 32.0°F).
Press the CAL button, the °C symbol (or the °F symbol) will stop flashing and the instrument
will gradually go to the calibration value of 0.0°C (or 32.0°F).
Second calibration point 197.0°C (or 386°F)
With the Pt100 simulator inserted in input A, simulate a temperature of 197.0°C (386°F).
Wait for the instrument measurement to become stable.
Press the CAL button, the °C symbol (or the °F symbol) will flash and the instrument will propose the calibration temperature of 197.0°C (or 386°F).
Press the CAL button again, the °C symbol (or the °F symbol) will stop flashing and the
instrument will return to normal operation, leaving the calibration process, and will gradually
go to the calibration value of 197.0°C (or 386°F).
After the second calibration point the procedure is complete and the instrument updates the calibration date of input B, stated in the reports.
TEMPERATURE CALIBRATION INPUT B WITH THE 4-WIRE Pt100 PROBE
In program P11, when ENTER is pressed, it is possible to enter the procedure for calibrating input
B for the 4-wire Pt100 probe.
Before entering program P11, insert the probe with which calibration is to be performed.
The instrument shows the temperature value measured at input B at the bottom of the display and
the message CAL at the top.
Instrument calibration comprises compensation of the offset (with the first calibration point) and
of the amplification of the instrument (with the second calibration point).
First calibration point 0.0°C (or 32.0°F)
Bring the calibration oven to a temperature of 0.0°C (or 32.0°F) and insert the probe to be
used with the instrument, connecting it to input B. When the instrument reading has become
stable, move on to the next step.
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Press the CAL button, the °C symbol (or the °F symbol) will flash and the instrument will propose the calibration temperature of 0.0°C (or 32.0°F).
Using the and keys, correct the temperature value indicated by the instrument being
tested to make it is the same as the one on the instrument whose probe is inserted in the
calibration oven.
Press the CAL button, the °C symbol (or the °F symbol) will stop flashing.
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Second calibration point 197.0°C (or 386°F)
Bring the calibration oven to a temperature of 197.0°C (or 386°F). When the instrument reading has become stable, move on to the next step.
Press the CAL button, the °C symbol (or the °F symbol) will flash and the instrument will propose the calibration temperature of 197.0°C (or 386°F).
Using the and keys, correct the temperature value indicated by the instrument being
tested to make it is the same as the one on the instrument whose probe is inserted in the
calibration oven.
Press the CAL button, the °C symbol (or the °F symbol) will stop flashing.
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After the second calibration point the procedure is complete and the instrument updates the calibration date of input B, stated in the reports.
NOTE: After the procedure for calibrating the Pt100 probe, to obtain correct measurements the
same probe used for calibration must be used.
DO 9505
Instrument input B
B
7
3
Instrument input A
A
6
8
5
1
SIGNAL
4
2
Probe Pt100 4 wire input
1
6
7
+5V
Pt100
8
GND
3 2
-5V
5 4
OUT
2.375mV/°C
GND
Probe Pt100 TP 870 series input
89
pH, ORP or ISE electrode
SIGNAL
GND
ENGLISH
METHOD OF USE
* After the measurement the pH electrode must be cleaned and kept in a saturated solution of KCl
or, failing that, in a buffer solution at pH 6.86.
* During transport or storage the sensitive part of the electrode must be closed with a protection
cap so that it is always well hydrated (damp). Depending on use and on the desired precision,
zero calibration (offset) may be carried out every 5÷20 days. Calibration of the second point (gain)
may be carried out once a month or more, unless higher levels of precision are required.
* If the electrode breaks or becomes faulty it may be replaced. In this case the electrode must be
recalibrated.
* Do not let the surfaces of the sensor come into contact with sticky surfaces or substances that
can corrode or damage the sensor
* Do not use the temperature probes in the presence of corrosive gases or liquids; the container in
which the sensor is housed is made of stainless steel AISI 316, while the container for the contact
probe is of AISI 316 plus silver and the thermocouple housing is of Inconel.
* Do not bend or force the contacts when inserting the connector.
* Do not bend or deform the probes as this could cause irreparable damage.
* Always use the most suitable probe for the measurement to be taken.
* Be careful with the range of use of the probe, measurements at limit values are possible only for
short periods.
* To obtain a reliable temperature measurement, too fast temperature variations must be avoided.
* Temperature probes for surface measurements must be held in a vertical position with respect to
the surface. Apply a drop of oil or heat-conductive paste between the surface and the sensor so
as to improve contact and reduce the reading time. Do not use water or solvents to do this.
* Temperature measurements on non-metal surfaces require a great deal of time on account of
their low heat conductivity.
* Always clean the probes carefully after use.
* The instrument is resistant to water but it is not watertight and should not therefore be immersed
in water. If it should fall into the water, take it out immediately and check that no water has infiltrated.
* The temperature sensor is not insulated from its external casing. Be very careful not to
come into contact with live parts (above 48V) as this could be dangerous not only for
the instrument but also for the operator, who could suffer an electric shock.
* Avoid taking measurements in the presence of high frequency sources, microwaves or large
magnetic fields, as the results would not be very reliable.
ERROR SIGNALS
During measurement or calibration, error signals may appear on the display which have the following meanings:
Err - Signal which appears during measurement when the value to be shown is out of scale, or
when the measurement is taken with a very low battery.
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E1 - Error signal which appears during calibration when the two buffer solutions used give mV readings which are too different from each other.
E2 - Error signal which appears during calibration when the two buffer solutions used give mV readings which are too close to each other (about 50 mV at 25°C).
E3 - Error signal which appears during calibration when the slope of the line pH/mV set for the two
buffer solutions is 20% lower than the rated value.
E4 - Error signal which appears during calibration when the slope of the line pH/mV set for the two
buffer solutions is 150% higher than the rated value.
E5 - Error signal which appears during calibration when the electrode offset value is too high in the
absolute value.
E6 - Indicates errors in the management of the internal clock and of the display.
E7 - Indicates errors in the management of the internal storage unit.
LOW BATTERY WARNING AND BATTERY REPLACEMENT
If the battery has run down, or if its voltage has reached the limit value of 6.5V, a beep sounds
every 10 seconds and the symbol appears permanently on the display. In these conditions the
battery should be replaced as soon as possible.
If you continue to use the instrument and the battery voltage falls as low as 5.5V, the instrument is
no longer able to ensure correct measurement and two Err codes are shown alongside the temperature values.
H
AFTER CHANGING THE BATTERY YOU MUST UPDATE THE CLOCK AND THE PARAMETERS P2, P3... AND SO ON.
To change the battery turn the instrument retaining screw in an anti-clockwise direction. After replacing it (with an ordinary 9V alkaline battery) close the instrument, inserting the tag into the slot provided, and turn the screw in a clockwise direction.
The stored data will not be lost even if the instrument remains without batteries for some instants.
Ensure that the instrument is switched off before changing the battery.
H
The symbol appears fixed to indicate that the battery is low. This indication prevails over all the
other signals which make use of the symbol. In RCD function the symbol flashes at a frequency of 2 Hz. In Auto Power Off function the symbol flashes at a frequency of 1 Hz. The flashing of the RCD function prevails over the flashing of Auto Power Off.
H
H
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FAULTY OPERATION WHEN SWITCHING ON AFTER CHANGING THE BATTERY
Repeat the battery changing procedure, waiting for a few minutes to allow the circuit condenser
capacities to be completely discharged, then insert the battery.
WARNING
- If the instrument is not to be used for a long period, it is better to remove the battery.
- If the battery is flat it must be replaced immediately.
- Take steps to avoid leakage of liquid from the battery.
- Use good quality leakproof batteries, alkaline if possible.
MAINTENANCE AND CLEANING OF THE ELECTRODE
Instrument storage conditions:
* Temperature: -10 to +50°C
* Humidity: less than 90% relative humidity; avoid the formation of condensation.
* Do not store the instrument in places where:
1. There is a high degree of humidity;
2. The instrument is exposed to direct sunlight;
3. The instrument is exposed to a source of high temperature;
4. There are strong vibrations;
5. There is steam, salt and/or corrosive gas.
* The instrument body is made of ABS plastic so it must not be cleaned with solvents which can
spoil plastic.
* Regular maintenance of the pH electrode ensures optimum performance, longer life and less
costs for part replacement.
The pH electrode should be checked every 10÷20 days for cracks, formations of salt crystals or
deposits around the porous septum.
Wash the saline deposits with distilled water. Various deposits around the porous septum and on
the pH-sensitive membrane may be removed by immersing the electrode in a 0.1 molar solution
of HCl or HNO3 for 15 minutes. A blocked porous septum may be cleared by immersion in
KCl 0.1 Mol at 70°C (60°C for calomel electrodes) for 15 minutes. Empty the reference electrode
and fill it with fresh electrolyte.
Immerse the electrode in a solution of KCl, identify the substance causing the blockage and use
a specific solvent. For example, protein deposits may be removed with 1% pepsin in 0.1 mole of
HCl; grease and oil may be dissolved in a detergent or a solution of methyl alcohol.
For an electrode to be always ready for use, it must always be well hydrated.
We advise keeping the electrode in a storage solution or in a saturated solution of KCl. If no KCl
is available, use a buffer solution with pH 6.86. Otherwise the electrode may be preserved by
covering it with a protective cap containing a saturated solution of KCl.
Do not use demineralized water. The level of the solution that fills the reference electrode must
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be higher than the level of the solution in which the electrode is immersed (a few centimetres
higher). This avoids a flow towards the internal solution in the reference electrode.
The electrode connector and the BNC input of the pH-meter must not be wet. A wet or dirty connector may be cleaned by washing it in a dehydrating solvent that does not leave residue (e.g.
alcohol).
If the electrode is disconnected from the instrument, close the BNC input with the plug provided.
Cleaning the electrode
Deposits
General deposits
Inorganic coatings
Metallic components
Oil, grease
Biologic-protein substances
Resin
Highly resistant deposits
Cleaning agents
Medium detergents
Solutions for cleaning glass
HCl 1 Mol/l
Complex agent (EDTA) or solvent
Pepsin 1% in 0.1 Mol HCl
Acetone
Hydrogen peroxide, sodium hypochlorite
MEASUREMENT OF THE pH VALUE
Connect the instrument to a pH electrode suitable for measuring requirements (e.g., use a pointed
electrode for measurements in cheese and meat, a flat electrode for measurements on surfaces,
etc.). Connect the temperature probe TP 870 and ensure that it is at the same temperature as the
pH electrode.
If the temperature probe is not available, set the temperature of the pH electrode manually. (Press
the CAL key, then the °C/°F key and use the and keys until the value corresponding to the
temperature to be analysed is reached). CAL again to confirm the value.
Note the pH value once the reading is stabilized. If you stir the pH electrode about in the solution to
be analysed you will observe a slight change in the reading.
This phenomenon is due to a change in the diffusion speed of the ions which migrate from the solution inside the reference electrode into the solution to be analysed.
If calibration is carried out while the buffer solution is being stirred (e.g. with a magnetic stirrer),
then measurements must also be taken while the unknown solution is being stirred. The same
applies to a still electrode. When the solution is stirred there is a quicker response and the readings
are more easily reproduced.
When passing from one solution to another with a notably different pH value, there is the
risk that residue of the first solution will cling to the electrode, thus threatening to alter the
pH value of the second solution.
Solutions with a low ionic concentration (low conductivity) are particularly prone to pollution.
However we do not advise cleaning the electrode with paper towels, rags, etc.
When the glass of the electrode is rubbed this generates an electrostatic charge that has a transitory worsening effect on reproducibility.
The most practical way of cleaning the electrode is to divide the solution you wish to analy-
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se into two parts: use the first part only for rinsing the electrode and take the measurement
in the second part.
MEASUREMENT OF THE pH OF THE EARTH
There are various methods of measuring the pH of the earth.
As the different methods give different results, it is essential to quote the method used as well as
the pH value obtained. The table shows the pH values obtained on immersing a combined pH electrode in a mixture of earth and distilled water.
Table 1 - Effect of the earth/water ratio on the pH value
ml of water added
to 100 g of earth
10
25
100
1000
pH of the suspension
earth 1
earth 2
earth 3
7.45
7.60
7.70
8.15
9.10
9.40
9.85
9.90
7.95
8.00
8.20
9.20
The glass electrode is immersed in the sediment (obtained by letting the suspension rest for a
time), while the porous septum (or the reference electrode if this is physically separate from the
glass electrode) remains in the liquid on top.
More reproducible recordings may be made by measuring the pH of a suspension of earth in a neutral salt solution. Solutions of KCl 1 Mol or CaCl 2 0.01 Mol are generally used.
These give pH values lower than those obtained for the same earth suspended in water.
Table 2 - pH values measured in different conditions
Earth
suspended in
distilled water
KCl 1 M
pH recorded in
liquid above
suspension
sediment
6.2
5.1
5.8
5.1
4.7
5.1
Furthermore, the value measured is the same in the solution, the suspension and the sediment
(contrary to what occurs when using a mixture with distilled water).
For some types of earth, the earth-water mixture has a very low electric conductivity; in these cases
the measurement is unstable and is not easily repeated. If on the other hand a solution of KCl is
used, excellent repeatability may be obtained even in these difficult cases.
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ERRORS IN MEASURING THE pH VALUE
There are basically two types of pH measurement error: instrumental errors and errors due to the
sensor (electrode). Instrumental errors (pH ±0.015) are generally negligible in comparison with those due to the electrode. Especially for values of pH > 12 and in the presence of Na+ ions there are
deviations from the ideal behaviour due to the composition of the pH sensitive glass (about pH 0.1).
Another source of error is the diffusion potential created at the ends of the porous septum.
For diluted solutions of acids, bases and salts with a concentration of less than 0.1 mole/litre there
are errors lower than pH ±0.05; in a base or a concentrated acid there may be errors of pH ±0.2.
These errors may be minimized by calibrating with solutions that have a pH value and an ionic concentration similar to that of the specimen.
In specimens with suspended particles there may be errors of up to pH ±2. These errors may be
eliminated by filtering the solution.
In solutions with a very low electric conductivity, pH measurements are unstable and are not easily
repeated; when a special solution is added (pHiX adjuster), the ionic concentration and consequently the conductivity are increased and the measurements become more stable. The change of pH
due to the addition of the pHiX adjuster is negligible (pH < 0.003).
The glass membrane of a pH electrode must always be well hydrated. If the electrode is
immersed in an anhydrous, water-greedy substance (such as alcohol), its hydrated layer may be
destroyed.
Likewise this layer may be destroyed if the electrode is allowed to dry in the air.
In contact with water the hydrated layer regenerates slowly, so the measurements are not reliable
in the first two hours (passing from dry to damp).
Hydrofluoric acid, some fluorine compounds with pH < 5, strongly alkaline solutions at a
high temperature and saline solutions in high concentration and at a high temperature may
attack the glass membrane, so it is not advised to carry out measurements in these conditions.
MEASURING THE REDOX POTENTIAL (ORP)
In order to measure the redox potential (ORP), combined electrodes made of a noble metal are
used, immersed in the solution to be analysed. Platinum is the most frequently used noble metal.
Before a platinum electrode can be used it must be cleaned mechanically using abrasive substances, then immersed in diluted hydrochloric acid and finally washed with water. In some cases, e.g.
if platinum has a catalysing effect or if the speed of response is slow (this also depends on the
reversibility of the reaction), it will be preferable to use a gold electrode. Gold is not recommended
in the presence of cyanide or chloride. The formation of air bubbles or other gases on noble metals
should be avoided.
Measurements are made by connecting a combined electrode for ORP measurement to the BNC
connector and selecting mV measurement with the pH/mV key.
Temperature compensation is not possible on account of the many factors that influence the ORP
(type of noble metal, valency of the reagents, pH of the solution, etc.).
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In order to have a means of comparison it is therefore convenient to record the ORP and the temperature of the solution to be analysed.
When measuring the redox potential there is no need to calibrate the electrode as the mV measured are always absolute mV.
MEASUREMENTS WITH SPECIFIC ION ELECTRODES
Specific ion electrodes possess the following characteristics:
1. The signal is a voltage that must be measured without charging the electrode (high impedance).
2. The signal is proportional to the logarithm of the ionic activity.
3. The signal does not depend on the sensitive area of the electrode.
Ideally, a specific ion electrode should be sensitive only to one ionic species (similarly to the almost
ideal situation of the pH electrode). In actual fact there is a more or less marked dependence on
other ions (or other gases if the electrode measures a dissolved gas, for example ammonia). The
degree of interference is specified by the manufacturers of selective ion electrodes.
In many cases the solution must be titrated beforehand to an optimal pH value and/or ionic concentration.
The solutions for preparing the specimens are called TISAB (Total Ionic Strength Adjustment
Buffer) or CONDISOL (Conditioning Solution).
The measuring technique (preparation of specimens) influences the measurement result and therefore it must be specified.
At 25°C a monovalent selective ion electrode (for example Na+) gives 59 mV for every decade of
concentration; for bivalent ions (e.g. Ca++), values of 29.5 mV/decade are obtained.
This means that an error in measurement of ±1 mV leads to an error in terms of concentration of
±4% with monovalent ions and ±8% with bivalent ions.
From the instrumental point of view it is possible to obtain greater precision than ±1 mV, however
this is not accompanied by a significant improvement of the final result, since the greatest limit is
caused by the diffusion potential of the reference electrode.
This potential is created at the ends of the porous septum and depends on ionic concentration.
With special reference electrodes and/or by titration, uncertainty may be less than ±1 mV.
Combined specific ion electrodes (ISE) may be connected directly to the BNC input.
However, if the specific ion electrode and the reference electrode are two distinct units, the reference electrode and the screening of the specific ion electrode must be connected to the external
metal part of the BNC connector, while the signal of the specific ion electrode must be applied to
the core (internal part) of the BNC connector.
The measurement may be carried out by measuring the mV (absolute), pressing the pH/mV key
after the instrument has been switched on. Specific ion electrodes are supplied with a chart or a
graph showing the ionic concentration as a function of the mV generated.
It must also be remembered that, according to Nernst’s law, measurements vary with the temperature of the electrode.
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TEMPERATURE MEASUREMENT
Temperature probes in the TP 870 series may be connected to the DO 9505. The types available
include TP 871 and TP 870 for immersion measurements, TP 870C surface probes, TP 870P
penetration probes and TP 870A probes for air and gas.
Connect the chosen probe to input B of the instrument (DIN 8-pole female). Switch the instrument
on with the ON/OFF key and press the °C/°F key to choose the temperature measuring unit.
The temperature value with the symbol of the chosen unit is shown at the bottom of the display.
The working range of the probes and their response time are specified in the table.
In surface measurements, apply a few drops of oil or conductive paste to improve the thermal contact between the measuring surfaces and the sensor, this improves the response time. Contact
measurements on plastic surfaces require a great deal of time on account of the low thermal conductivity coefficient of plastics.
SERIAL INTERFACE RS-232C
The instrument is equipped with the standard serial interface RS-232C, galvanically insulated; it is
supplied with the adapter cable CP 232 C. The following signals are available on the SUB D 9-pin
male connector of the DO 9505.
PIN
3
2
5
SIGNAL
TD
RD
GND
DESCRIPTION
Datum transmitted by the instrument
Datum received by the instrument
Reference logic mass
NOTE: The deflector on the connector of the adapter cable CP 232 C must be turned to COMPUTER or PRINT position, depending on the chosen connector.
The signals present in pins 2 and 3 are at logic levels compatible with the standard
RS-232C.
The transmission parameters with which the instrument is supplied are:
- Baud Rate
19200 Baud
- Parity
None
- No. bits
8
- Stop bit
1
The data transmission speed may be changed by pressing the PROG key on the instrument to alter
the set-up parameter P3. The possible Baud Rates are: 19200, 9600, 4800, 2400, 1200, 600, 300.
The other transmission parameters are fixed.
All the messages reaching and leaving the instrument must be inserted in a “Communication frame” with the following structure:
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Record-cr
where:
-Record-cr-
constitutes the message
Carriage Return (ASCII 0D)
HOST COMMANDS
COMMAND
REPLY
AA
AG
AH
SA
SB
SC
SD
SE
SI
S*
Xoff (Ctr-S)
Xon (Ctr-Q)
Type of terminal
pHMETER - DL
Firmware Version
V. x R. x
Firmware Date
dd/mm/yy
pH request
pH (current)
mV request
mV (current)
Temp. request
temperature probe TP 870...
Temp. request
4-wire Pt100 temperature probe
Temp. request
manually set temperature
Terminal Type
pHMETER - Pt100
NC
Stops transmission in progress
Resumes transmission in progress
COMPUTER
8
7
6
5
4
3
2
5 4
25 24 23 22 21 20 19 18 17 16 15 14
9
98
3
8
1
6
NC
NC
11
12
24
TEST
23
13
25
NC
10
22
2
7
NC
NC
9
21
NC
NC
NC
8
20
NC
7
19
NC
6
18
DTR
5
17
DCD
GND
DSR
CTS
RTS
1
4
16
NC
TC
NC
13 12 11 10 9
3
15
NC
2
14
PRINT
RC
TXD
1
COMPUTER
RXD
SCR
PRINT
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EXAMPLE OF A REPORT PRINTED BY THE INSTRUMENT
pHMETER - Data Logger
Immediate serial report
DATE
TIME
------- A ------
---- B ---
31-12-97 13:55:16
31-12-97 13:55:18
31-12-97 13:55:20
7.00 pH 0.0 mV
7.00 pH - 0.1 mV
7.00 pH - 0.1 mV
20.0°C
20.0°C
20.0°C
Max. Values
:
Min. Values
:
Medium Values :
7.00 pH 0.0 mV
7.00 pH - 0.1 mV
7.00 pH 0.0 mV
20.0°C
20.0°C
20.0°C
Instrument Calibration date: 12-12-97
Probe Calibration date: 21-12-97
Buffer Solution: 6.86 pH 25.0°C
Buffer Solution: 9.18 pH 25.0°C
pHMETER - Data Logger
Immediate serial report
DATE
TIME
------- A ------
---- B ---
31-12-97 13:55:35
31-12-97 13:55:37
0.00 pH 0.0 mV
0.00 pH 0.0 mV
0.0°C
0.0°C
Max. Values
:
Min. Values
:
Medium Values :
0.00 pH 0.0 mV
0.00 pH 0.0 mV
0.00 pH 0.0 mV
0.0°C
0.0°C
0.0°C
Instrument Calibration date: 12-12-97
Probe Calibration date: 21-12-97
Buffer Solution: 6.86 pH 25.0°C
Buffer Solution: 9.18 pH 25.0°C
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pHMETER - Data Logger
Remote memory report
DATE
TIME
------- A ------
---- B ---
31-12-97 13:55:45
31-12-97 13:55:47
7.00 pH 0.1 mV
7.00 pH 0.0 mV
20.0°C
20.0°C
Max. Values
:
Min. Values
:
Medium Values :
7.00 pH 0.1 mV
7.00 pH 0.0 mV
7.00 pH 0.0 mV
20.0°C
20.0°C
20.0°C
Instrument Calibration date: 12-12-97
Probe Calibration date: 21-12-97
Buffer Solution: 6.86 pH 25.0°C
Buffer Solution: 9.18 pH 25.0°C
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DO 9505 DIAGRAM
Temperature probe
pH electrode
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INSTRUCTIONS FOR CONNECTING DELTA OHM INSTRUMENTS TO A PC
WITH WINDOWS OPERATIVE SYSTEM
Hardware connection:
1) The measuring instrument must be switched off.
2) Connect the serial gate of the measuring instrument to a free serial gate on the PC
(COM1/COM2) using the special DELTA OHM RS-232C cable.
NOTE: The CP 232 C cable ends in a female 25-pin connector; if your PC does not have a compatible connector, use the adapters normally found on the market to make the connection.
3) Turn the switch on the CP 232 C cable to COMPUTER position.
Software connection with WINDOWS 3.1:
A) Start WINDOWS.
B) Select ACCESSORIES (2 click)
C) Select TERMINAL and activate the communications program (2 click)
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D) To alter the communication settings of the terminal, in order to make them compatible with those
of the measuring instrument used (unless a terminal setting file has already been saved):
select SETTINGS in the terminal window (1 click)
select COMMUNICATIONS from the menu (1 click)
the COMMUNICATIONS window for setting the communication procedures will appear on
the screen; set:
TRANSMISSION SPEED: 19200 which must correspond to the speed set on the
instrument (1 click)
DATA BITS: 8 (1 click)
STOP BITS: 1 (1 click)
PARITY: None (1 click)
FLOW CONTROL: Xon/Xoff (1 click)
CONNECTOR: COM1 or COM2 depending on the gate used for connection (1 click)
CHECK PARITY and SHOW CARRIER must remain unmarked
OK to confirm the setting (1 click)
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E) To set the correct character type:
select SETTINGS in the terminal window (1 click)
select TERMINAL PREFERENCES in the pull-down window (1 click)
the TERMINAL PREFERENCES window appears on the screen; set:
mark local Echo (1 click),
Character type: Terminal,
Translation: None,
leave the rest unchanged.
OK to confirm the setting (1 click)
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F) If you want to save this terminal setting:
select FILE from the terminal window (1 click)
select SAVE AS from the menu and the SAVE FILE AS window will appear (1 click)
type the name of the terminal setting file (max. 8 characters) on the line provided
OK to confirm and save the setting (1 click)
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G) To receive and store data from an instrument:
select TRANSFER from the terminal window (1 click)
select RECEIVE TEXT FILE from the menu and the window will appear (1 click)
type the name of the file in which data are to be stored (max. 8 characters) on the line provided
OK to confirm and start storage (1 click)
At this point the terminal is ready to receive data from the measuring instrument. Everything sent by
the measuring instrument will be stored in the file indicated previously.
H) Switch on the measuring instrument.
When the instrument has completed the switching-on routine, activate the immediate unloading of
data at the set rate, pressing the SERIAL OUTPUT button, or activate the unloading of the data
stored in the internal memory with the program P1 (press the PROG button twice) and press the
ENTER button.
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I) End of storage of the data sent by the instrument
select TRANSFER from the terminal window (1 click)
to end storage, select END from the menu (1 click)
The software returns to the terminal window.
L) End use of the TERMINAL
select FILE from the terminal window (1 click)
select QUIT from the menu (1 click)
The text file, containing the data received from the measuring instrument connected to the PC, is
now stored in our computer. To read and process the file obtained we can use any text or table processing program in the Windows environment (WORD, EXCEL, WORKS, etc.).
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Software connection with WINDOWS 95
A) After starting WINDOWS 95, select START, PROGRAMS, ACCESSORIES, HYPERTERMINAL.
Run HYPERTRM (2 click).
B) Name of the communication.
In the window “Description of connection”, give a name to the communication that you want to
activate and choose an icon (in subsequent communications it will be possible to activate directly the icon chosen in place of HYPERTRM, automatically recovering all the settings saved with
the icon).
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C) Setting communication
- select FILE from the Hyper Terminal window (1 click)
- select PROPERTIES from the menu (1 click) and the “Properties” window will appear
- on the “telephone number” card, for the Connect property, choose “directly to COM1” or
COM2, depending on the serial gate that you intend to use for communication with the measuring instrument.
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- on the “telephone number” card, select CONFIGURE (1 click) and the “Gate settings” card
will appear.
- on the “Gate settings” card select:
BITS PER SECOND: 19200
DATA BITS: 8
PARITY: None
STOP BITS:
FLOW CONTROL: Xon/Xoff (1 click)
OK to confirm the gate setting (1 click)
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- select SETTINGS to display the “Settings” card
- on the “Settings” card, for the “Emulation” property, select: TTY
- OK to confirm the “Properties” set (1 click)
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D) To set the correct type of character:
- select DISPLAY in the Hyper Terminal window (1 click)
- select CHARACTER in the pull-down window (1 click)and the window for selecting the character appears on the screen; set:
- Terminal.
- OK to confirm (1 click)
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E) To receive and store data from an instrument:
- select CALL from the Hyper Terminal window (1 click)
- select CONNECT from the menu
At this point the Hyper Terminal software is able to receive data from the measuring instrument and
store them in the set file.
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To store data from an instrument:
- select TRANSFER from the Hyper Terminal window (1 click)
- select CAPTURE TEXT from the menu (1 click) and the window will appear where you have
to set the name of the file in which to store the data received from instrument
- type the name of the file in which data are to be stored on the line provided
- OK to set the name of the receiving file (1 click)
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F) To end receiving data from an instrument:
- select TRANSFER from the Hyper Terminal window (1 click)
- select CAPTURE TEXT from the menu (1 click)
- select END from the sub-menu (1 click)
At this point data reception form the instrument is ended and the file stored in the computer can be
used with any of the software packages used with WINDOWS 95.
G) To quit running the Hyper terminal:
- select FILE from the Hyper Terminal window
- select QUIT from the menu
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TECHNICAL CHARACTERISTICS DO 9505
- Display: dual LCD with 31/2 digits, height 12.5 mm, with symbols.
- Inputs: n° 2.
Input A electrode for measuring pH, redox potential, or specific ion electrode; impedance 10x1012
ohm.
Input B for temperature probes, series TP 870 (Pt100 sensor with amplification and linearization
circuit) or 4-wire Pt100 probes with direct input.
- Instrument measuring range:
* pH
-2.00...16.00 pH
* mV
-1999...1999 mV
* temperature -50...200°C.
- Instrument precision:
pH
mV
temperature
instrument precision
from 18 to 25°C
instrument precision
from -10 to 18 and from 26 to 50°C
± 0.02 pH
± 0.2 mV
± 0.2 °C
0.02 pH + 0.001 pH/°C
0.2 mV + 0.01 mV/°C
0.2 °C + 0.01 °C/°C
- Resolution:
* pH
0.01 pH
* mV
0.1 mV in the range -199.9...+199.9 mV, 1 mV beyond
* temperature 0.1°C in the range -50.0...+199.9°C, 1°C beyond.
- Instrument conversion frequency: 2 per second on both inputs.
- Temperature compensation in pH measurement: 50°C +200°C manual or automatic
- Instrument working temperature: -5...+50°C, 0...90% R.H., no condensation.
- Storage temperature: -20...+60°C.
- Power supply: 9V battery, lifetime with alkaline battery 100 hours.
- Connectors: input A female BNC, input B DIN 41524 female eight-pole circular connector, serial
gate SUB D male 9-pole.
- Instrument case: ABS.
- Dimensions: instrument alone 210 x 72 x 40 mm.
kit 370 x 295 x 85 mm.
- Weight: instrument alone 350 gr.
kit 1600 gr.
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ORDER CODE
DO 9505KE : Diplomatic carrying case, instrument DO 9505, temperature probe TP 871, epoxy
electrode with cable L=1 metre, pH 6.86 and pH 4.01 buffer solutions, connecting
cable CP 232 C.
DO 9505K : Diplomatic carrying case, instrument DO 9505, temperature probe TP 871, without
electrode, pH 6.86 and pH 4.01 buffer solutions, connecting cable CP 232 C.
DO 9505 : Flexible case, instrument DO 9505.
BUFFER SOLUTIONS, ELECTRODES, PROBES AND CONNECTING CABLES
HD 8642 : Buffer solution pH 4.01, 200 cc.
HD 8672 : Buffer solution pH 6.86, 200 cc.
HD 8692 : Buffer solution pH 9.18, 200 cc.
CP
: Extension cable 1.5 mt., with S7 screw connector on one end, BNC male connector on
the other.
GK 20 : Combined pH electrode with GEL, S7 screw connector, made of EPOXY Ag/AgCl sat KCl.
GK 30 : Combined pH electrode, 1 mt. cable, with GEL, body made of EPOXY Ag/AgCl sat KCl
(SPARE FOR KITS).
GK 60 : Combined pH electrode with 2 diaphragms, S7 screw connector, filling type, glass
body, Ag/AgCl sat KCl.
GK 70 : Combined pH micro electrode, diam. 6 x L=70 mm with S7 screw connector, filling
type, glass body, Ag/AgCl sat KCl.
GK 80 : Combined pH electrode with tip, S7 screw connector, filling type, glass body, Ag/AgCl
sat KCl.
GK 90 : PLATINUM REDOX electrode with screw connector, filling type, glass body.
TP 871 : Immersion temperature probe, diam. 3 x 90 mm, measuring range -60...+200°C
TP 870 : Immersion temperature probe, diam. 3 x 230 mm, measuring range -60...+400°C
TP 870P : Penetration temperature probe, diam. 4 x 150 mm, measuring range -60...+400°C
TP 870C : Contact temperature probe, diam. 5 x 230 mm, measuring range 0...+400°C
TP 870A : Air temperature probe, diam. 4 x 230 mm, measuring range 0...+300°C
CP 232 C: Connecting cable from SUB D female 9-pole to SUB D female 25-pole, for serial output
RS-232C.
GUARANTEE
This instrument is strictly inspected before being sold. However if there should be any defect due to
manufacture and/or transport, apply to the dealer from whom you bought the instrument.
The guarantee period is 2 (two) years from the date of purchase. During this period all defects
found by us will be repaired free of charge, excluding those due to incorrect use and careless handling. The probes and sensors are not covered by the guarantee, as they can be irreparably damaged after only a few minutes of incorrect use.
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EXAMPLES OF USE OF THE KEYBOARD
1.
Switches the instrument on or off.
2.
Blocks or releases updating of the display.
3.
Allows relative values to be displayed, stored or sent immediately onto the serial
line.
4.
Pressing DATA CALL repeatedly gives:
1.
pH
°C
The Maximum value of the probes
connected to inputs A and B
MAX
2.
pH
°C
MIN
3.
The Minimum value of the probes
connected to inputs A and B
CAL
pH
°C
The Mean value of the probes connected to inputs A and B
MED
4.
pH
°C
118
Return to normal operating mode
ENGLISH
5.
:
Confirms the selected
value and returns to
normal operating mode
without confirming the
changed values
pH
=
=
+
=
°C
= Unloads data from the memory
+
the memory (Memory Clear)
= Erases
Return to normal operating mode
Hours
Minutes
Seconds
=
+
+
=
Confirms the selected
value and returns to
normal operating
mode
=
Confirms the selected
value and returns to
normal operating
mode
+
Sets reading or storage interval
(from 1 sec. to 12 hours)
=
+
+
+
Sets BAUD RATE
=
+
+
+
Sets year
00, 01, 02 ... 99
eg. 2000
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=
+
+
+
Sets month
01, 02, 03 ... 12
eg. 01 january
=
+
+
+
Sets day
01, 02, 03 ... 31
eg. 01
=
+
+
+
Sets hours
01, 02, 03 ... 24
eg. 01 p.m.
Confirms the selected
value and returns to noroperating mode,
storing the set date and
time.
= mal
=
+
+
+
Sets minutes
01, 02, 03 ... 59
eg. 01 minutes
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=
+
+
Confirms the selected
and returns to
= value
normal operating mode
Enables self cut-out
during storage with an
intervention time equal to
or greater than 1 minute.
+
The instrument does not cut out
automatically during storage.
=
+
Calibration Input A
=
+
Calibration Input B
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6.
Before pressing the key the Baud Rate must be set, which has to be compatible with
the printer or computer to which the instrument is to be connected.
A) Setting the BAUD RATE:
+
+
B) Setting the reading or storage interval:
hours
0-12
+
minutes
0-59
seconds
0-59
=
Set time 1 minute
C) Dump data on the serial line
pH
pH
°C
°C
Start serial dumping.
End serial dumping.
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7.
When the key is pressed the instrument starts
to store and update the MAX, MIN and MED
value.
pH
RCD
°C
beep
When it is pressed for a few seconds it emits a beep, clears the Maximum, Minimum
and Mean value and starts again, or updates the MAX, MIN, MED values.
RCD
s
8.
When used with the and
manual) of any pH electrode.
t keys the CAL key allows calibration (automatic or
pH
AUTOMATIC
pH
+
=
CAL
+
pH
1st calibration
pH
pH
+
=
+
=
MANUAL
CAL
CAL
pH
AUTOMATIC
pH
+
=
CAL
+
pH
2 calibration
pH
pH
nd
+
=
+
MANUAL
CAL
CAL
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=
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9.
In programming, erases the memory in P1 function.
10.
the memory (Memory Clear)
= Erases
Return to normal operating mode
+
Memory
Clear
Display temperature in °C or °F.
pH
°C
pH
°F
11.
Storage.
Serial
Out
pH
pH
°C
°C
CAL
Memory
START Memory
STOP Memory
pH
DUMP
memory data
+
=
°C
Serial
Out
Memory
12.
The measurement may be made in pH or mV.
pH
°C
mV
°C
124
CE CONFORMITY
Safety
Electrostatic discharge
Electric fast transients
Voltage variations
Electromagnetic interference
sucseptibility
Electromagnetic interference
emission
EN61000-4-2, EN61010-1 level 3
EN61000-4-2 level 3
EN61000-4-4 level 3
EN61000-4-11
IEC1000-4-3
EN55020 class B
GUARANTEE CONDITIONS
All our appliances have been subjected to strict tests and are guaranteed for 24 months from date
of purchase. The Company undertakes to repair or replace free of charge any parts which it considers to be inefficient within the guarantee period. Complete replacement of the instrument is excluded and no requests for damages are recognized, whatever their origin. Repairs are carried out in
our own Technical Service Department. Transport expenses are borne by the buyer. The guarantee does not include: accidental breakages due to transport, incorrect use or neglect, incorrect connection to voltage different from that contemplated for the instrument, probes, sensors, electrodes and all accessories. Furthermore the guarantee is not valid if the instrument has
been repaired or tampered with by unauthorized third parties, or adjusted for faults or casual
checking. The guarantee is valid only if all parts of the guarantee card have been filled in. Any
instruments sent for repairs must be accompanied by their guarantee certificate. For all disputes
the competent court is the Court of Padua.
SIT CALIBRATION
CENTRE N° 124
DELTA OHM SRL
VIA G. MARCONI, 5 - 35030 CASELLE DI SELVAZZANO (PD) - ITALY
TEL. 0039-0498977150 r.a. - FAX 0039-049635596
e-mail: deltaohm@tin.it - Web Site: www.deltaohm.com
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