Delta OHM HD2306 User manual

Our instruments' quality level is the results of the product continuous development. This
can bring about differences between the information written in this manual and the
instrument that you have purchased. We cannot entirely exclude errors in the manual, for
which we apologize.
The data, figures and descriptions contained in this manual cannot be legally asserted. We
reserve the right to make changes and corrections without prior notice.
HD2306.0
REV. 1.3
Nov.
,
10th 2005

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Conductivity meter – Thermometer
HD2306

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HD2306.0
1. Input for probes, 8-pole DIN45326 connector.
2. Battery symbol: displays the battery charge level.
3. Function indicators.
4. Secondary display line.
5. DATA/ENTER key: during normal operation displays the maximum (MAX), the minimum
(MIN) and the average (AVG) of current measurements. To reset the previous values and restart
with a new measurement session, press DATA until the message "FUNC CLR" appears, then
use the arrows to select YES and confirm using ENTER. In the menu, confirms the current
selection.
6. χ/TDS key: selects the display of conductivity, resistivity, or total dissolved solids (TDS); in
the menu, resets the value set with the arrows. In calibration mode, allows you to exit
calibration.
7. key: in the menu, increases the current value. In calibration mode, increases the displayed
nominal buffer value.
8. °C/°F/MENU key: it allows selection of the unit of measurement; when pressed together with
the DATA key, it allows to open the menu. To exit the menu, press the MENU key at any time.
9. CAL: starts the calibration procedure.
10. /REL key: enables the relative measurement (displays the difference between the current
value and the logged value when the key is pressed); press the key again to return to the normal
measurement. In the menu, decreases the current value. In calibration mode, decreases the
displayed nominal buffer value.
11. ON-OFF/AUTO-OFF key: turns the instrument on and off.
12. MAX (maximum value), MIN (minimum value) and AVG (average value) symbols.
13. Main display line.
14. Line for symbols and comments.

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TABLE OF CONTENTS
1. GENERAL CHARACTERISTICS............................................................................................................................. 5
2. DESCRIPTION OF THE FUNCTIONS .................................................................................................................... 6
3. THE PROGRAMMING MENU ................................................................................................................................. 9
4. CONDUCTIVITY MEASUREMENT...................................................................................................................... 11
4.1 STANDARD PROBE................................................................................................................................................... 11
4.2 4-ELECTRODE OR 2-ELECTRODE PROBES ................................................................................................................. 12
4.3 CELLS WITH TEMPERATURE SENSOR ....................................................................................................................... 12
4.4 CHOOSING THE CELL CONSTANT ............................................................................................................................. 12
4.5 AUTOMATIC OR MANUAL CONDUCTIVITY COMPENSATION...................................................................................... 13
4.6 CALIBRATION OF THE PROBE................................................................................................................................... 13
4.6.1 Automatic calibration of conductivity using memorized buffer solutions ..................................................... 13
4.6.2 Manual calibration of conductivity using non memorized buffer solutions...................................................14
4.6.3 Table of buffer solution at 147μS/cm, 1413μS/cm, 12.88mS/cm and 111.8mS/cm ...................................... 16
4.7 DIRECT INPUT INTO Pt100 AND Pt1000 TEMPERATURE PROBES .............................................................................. 16
4.7.1 Temperature measurement ............................................................................................................................. 16
4.7.2 Connecting the TP47 connector ..................................................................................................................... 17
5. WARNINGS................................................................................................................................................................ 20
6. INSTRUMENT SIGNALS AND FAULTS .............................................................................................................. 21
7. INSTRUMENT STORAGE....................................................................................................................................... 21
8. LOW BATTERY WARNING AND BATTERY REPLACEMENT ..................................................................... 22
8.1 WARNING ABOUT BATTERY USE.............................................................................................................................. 22
9. NOTES ABOUT WORKING AND OPERATIVE SAFETY ................................................................................. 23
10. TECHNICAL CHARACTERISTICS .................................................................................................................... 24
10.1 TECHNICAL INFORMATION ON THE CONDUCTIVITY METER –THERMOMETER ...................................................... 24
10.2 ON LINE INSTRUMENT PROBES AND MODULES TECHNICAL DATA................................................... 26
10.2.1 2 and 4 electrode conductivity probes......................................................................................................... 26
10.2.3 4 wire Pt100 and 2 wire Pt1000 Temperature probes ................................................................................. 26
11. ORDER CODES ....................................................................................................................................................... 27
11.1 CONDUCTIVITY PROBES ........................................................................................................................................ 27
11.2 STANDARD CONDUCTIVITY CALIBRATION SOLUTIONS .......................................................................................... 27
11.3 TEMPERATURE PROBES ......................................................................................................................................... 27

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1. GENERAL CHARACTERISTICS
The Conductivity meter – Thermometer Model HD2306.0 is a portable instrument, fitted with a
large LCD display for excellent visualization of the measured data, that allows measurement of the
following:
•conductivity;
•liquid resistivity;
•total dissolved solids (TDS);
with combined 4-ring or 2-ring conductivity/temperature probes.
Temperature only is measured by Pt100 or Pt1000 immersion, penetration or contact probes.
The probe calibration can be performed automatically in one or more of the 147μS, 1413μS,
12880μS or 111,800μS/cm conductivity calibration solutions (see chapter 4).
Using the Max, Min and Avg function of this instrument respectively obtains the maximum,
minimum or average values.
Other available functions are:
•the relative measurement REL;
•the automatic turning off which can also be disabled.
See chapter 2 for further details.

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2. DESCRIPTION OF THE FUNCTIONS
The keyboard of the Conductivity meter – Thermometer Model HD2306.0 is composed of double-
function keys. The function on the key is the "main function", while the one above the key is the
"secondary function".
When the instrument is in standard measurement mode, the main function is active.
Once the Settings Menu has been opened, by pressing simultaneously the DATA+°C/°F keys, the
secondary function is enabled.
The pressing of a key is accompanied by a short confirmation "beep": a longer "beep" sounds if the
wrong key is pressed. Each key specific function is described in detail below.
This key has two functions:
•ON/OFF: to turn the instrument on press ON, to turn it off press OFF.
The turning on enables all display segments for a few seconds, starts an Auto-test including the
detection of the probe connected to the input, and sets the instrument ready for normal
measurement. The following is displayed:
MIN
cm
min s
2
3
m
µ
m
k
>>>
•AUTO/OFF: the AutoPowerOff function can be disabled by simultaneously pressing this key
and the "CAL" key when turning the instrument on.
During turning on, should no temperature probe be connected, the last manually-set temperature
appears in the secondary line. The unit of measurement symbol (°C or °F) starts blinking, and a
letter "m" meaning "manual" appears next to the battery symbol.
Caution! Replace the probes when the instrument is off.
The instrument has an AutoPowerOff function that automatically turns the instrument off after about
8 minutes if no key is pressed during the intervening time. Press simultaneously the ON/OFF key
and the CAL key to disable this function.
In this case, remember to turn the instrument off using the ON/OFF key: disabling of the automatic
turning off is shown by the blinking battery symbol.
ON-OFF and AUTO-OFF key
Disabling of the automatic turning off

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The χ/TDS/ESC key has two functions:
•χ/TDS: pressing this key in sequence selects the display of: conductivity, resistivity, or total
dissolved solids (TDS).
•ESC: once the MENU has been opened with the DATA+°C/°F keys, the χ/TDS key will allow
to cancel the parameters set using the and arrows.
•In calibration mode, it allows to exit calibration.
The DATA key is used for the following functions:
•DATA: during normal measurement, by pressing this key once the maximum (MAX) value of
the measurements captured by the probe connected to the instrument is displayed, updating it
with the acquisition of new samples;
-by pressing this key again the minimum (MIN) value is displayed;
-by pressing this key a third time the average (AVG) value is displayed.
The acquisition frequency is once a second.
The MAX, MIN and AVG values remain in the memory until the instrument is on, even after
exiting the DATA display function. When the instrument is off, the previously memorized data
are cleared. Upon turning on, the instrument automatically starts memorizing the MAX, MIN
and AVG values.
To reset the previous values and start with a new measurement session:
•press DATA until the FUNC_CLRD message appears;
•use the and arrows to select YES;
•confirm by pressing DATA/ENTER.
•ENTER: once the MENU has been opened with the DATA+°C/°F keys, the DATA key will
perform the ENTER function and the MENU can be browsed and the displayed parameter
confirmed. In calibration mode, acquires the nominal buffer value.
Once the MENU has been opened with the °C/°F/MENU and DATA keys, the key will allow to
increase the value of the selected parameter.
ke
y
χ
/TDS/ESC key
DATA/ENTER key

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The C/°F key is used for the following functions:
•°C/°F: pressing this key selects the unit of measurement of temperature in Celsius (°C) or
Fahrenheit (°F) degrees.
•MENU: in the menu five items can be set (see chapter 3):
•K CELL (Cell constant)
•ALPH_T (Temperature coefficient αT)
•REF_TEMP (Reference temperature)
•TDS (Conversion factor χ/TDS)
•Probe type
-the menu is opened by pressing simultaneously DATA+°C/°F: the first item of the instrument
programming menu will appear;
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
Press this key to start the calibration procedure (see chapter 4).
The "" key is used for the following functions:
•: once the MENU has been opened with the DATA+°C/°F keys, the key will allow to
decrease the value of the selected parameter.
•REL: it displays the difference between the current value and that measured on pressing the
key. The REL message is displayed on the left. To return to the normal measurement, press the
key again.
UNIT/MENU key
CAL key

/REL key

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3. THE PROGRAMMING MENU
To access to the menu press simultaneously the following keys:
The items to be set are listed (in this order):
1. K CELL (Cell constant):sets the conductivity probe's cell constant nominal value. The values
0.1, 0.7, 1.0 and 10 cm-1 (with tolerances from –30% to +50% of nominal value) are
admitted.
Caution! The cell constant must be inserted before starting the probe calibration.
An ERR signal is generated if the cell constant's actual value exceeds the limits –30% or +50%
of nominal value. In this case it is necessary to check that the value set is correct, that the
calibration solutions are in good state, and then proceed with a new calibration. The cell
constant change entails resetting the previous calibration.
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
2. ALPH_T (Temperature coefficient αT):the temperature coefficient αTis the percentage
measurement of the conductivity variation according to temperature and is expressed in %/°C
(or %/°F). The admitted values vary from 0.00 to 4.00%/°C.
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
3. REF_TEMP (Reference temperature): it indicates the temperature to which the displayed
conductivity value is standardized and can be equal to 20°C or 25°C.
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
4. TDS (Conversion factor χ/TDS): it represents the ratio between the measured conductivity
value and the total quantity of dissolved solids in the solution, expressed in mg/l (ppm) or g/l
(ppt). This conversion factor depends on the nature of the salts present in the solution: in the
field of water quality treatment and control, where the main component is CaCO3 (Calcium
Carbonate), a value of 0.5 is usually used. For agriculture water, for fertilizers preparation, and
in hydroponics, a factor of about 0.7 is used. The range is 0.4...0.8:
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.

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5. Probe type: the message "PRBE_TYPE" is scrolled in the comment line. The main line in the
center of the display shows the type of temperature probe connected to the instrument.
Conductivity/temperature combined probes with Pt100 or Pt1000 sensor, or temperature only
probes can be connected to the input.
•4 wire Pt100
•2 wire Pt1000
Upon being turned on, the instrument automatically detects the temperature probes: the Probe
Type menu item is configured by the instrument and cannot be modified by the user. If no
temperature probe or combined probe with temperature sensor is connected, the instrument
displays a dotted line "- - - -".

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4. CONDUCTIVITY MEASUREMENT
The Conductivity meter – Thermometer Model HD2306.0 works with:
•combined conductivity/temperature probes;
•4-electrode and 2-electrode only conductivity probes;
•temperature probes.
The 4 wire Pt100, 2 wire Pt1000 probes may be used for measuring temperature, which is used for
the automatic compensation of the conductivity.
The instrument obtains the following from the measurement of conductivity:
•the liquid resistivity measurement (Ω, kΩ, MΩ);
•the total dissolved solids (TDS) concentration according to the χ/TDS conversion factor which
can be modified using the menu (see chapter 3).
The conductivity, resistivity, or TDS (total dissolved salts) indication is displayed in the main line,
while the secondary line shows the temperature.
The conductivity probes must be periodically calibrated. To facilitate this operation, four automatic
calibration solutions are provided:
•0.001 Molar KCl solution (147μS/cm @25°C),
•0.01 Molar KCl solution (1413μS/cm @25°C),
•0.1 Molar KCl solution (12880μS/cm @25°C),
•1 Molar KCl solution (111800μS/cm @25°C),
User calibration of the temperature sensors is not required.
The probes are detected during turn on, and this cannot be performed when the instrument is
already on, therefore if a probe is connected and the instrument is on, it is necessary to turn it
off and on.
4.1 STANDARD PROBE
The instruments are provided with the standard 4-electrode conductivity/temperature combined
probe, SP06T.
The cell measurement zone is delimited by a bell in Pocan.
A positioning key, present in the probe's end part, orients the bell correctly when the probe is
introduced.
For cleaning, simply pull the bell along the probe's axis without rotating it.
It is not possible to perform measurements without this bell.
This probe's temperature measuring range is -50…+90°C.

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4.2 4-ELECTRODE OR 2-ELECTRODE PROBES
The Conductivity meter – Thermometer Model HD2306.0 uses 4-electrode or 2-electrode probes
for conductivity measurement.
The 4-electrode probes are preferred to measure high conductivity solutions, either over an
extended range or in presence of pollutants.
The 2-electrode probes operate in a shorter measurement range but with an accuracy comparable
with the 4-electrode probes.
The probes can be in glass or plastic: the first can work in presence of aggressive pollutants, the
latter are more resistant to collisions, and so more suitable for industrial use.
4.3 CELLS WITH TEMPERATURE SENSOR
The probes fitted with built-in Pt100 temperature sensor, measure conductivity and temperature at
the same time: this allows automatic correction of the effect of the latter on the solution
conductivity.
4.4 CHOOSING THE CELL CONSTANT
The cell constant Kcell is a piece of information which characterizes the cell and depends on its
geometry: it is expressed in cm–1.
There is no cell capable of measuring the entire conductivity scale accurately enough.
Consequently, cells with different constants are used allowing good measurements on different
scales.
The cell with constant K = 1cm–1 allows measurements from low conductivity up to relatively high
conductivity.
The theoretical measurement cell is made of two 1 cm2metallic plates separated one from the
other by 1 cm. This type of cell has a cell constant Kcell of 1 cm–1.
NOTE: the number, form, material and dimensions of the plates are very different from model to
model, from manufacturer to manufacturer.
The low constant K probes are preferably used for low conductivity values, the high constant K
probes for high values.
The indicative measurement range is reported in the following diagram:

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4.5 AUTOMATIC OR MANUAL CONDUCTIVITY COMPENSATION
The conductivity measurement refers to a standard temperature, called reference temperature
T_REF: that is, the instrument proposes the conductivity you would get if the temperature were
T_REF. This temperature could be 20°C or 25°C according to the setting in the T_REF menu item
(see chapter 3).
The conductivity increase per each grade of temperature variation is a characteristic of the solution
and is indicated by the term "temperature coefficient αT": most solutions are within these values,
from 0.00 to 4.00%/°C. The default value is 2.00%/°C.
When a combined probe with temperature sensor is present, the instrument automatically applies
the temperature compensation function, and proposes the measurement using the reference
temperature T_REF according to the coefficient αTon the display.
In absence of the temperature probe, the lower display shows the manually set compensation
temperature (default=25°C).
To point this condition out, the °C or °F symbol blinks intermittently near the temperature value.
On the display an "m" (manual) is turned on near the battery symbol (if on).
How to manually change the temperature
To manually change the compensation temperature, proceed as follows:
•press the °C/°F key once: the indicated temperature value starts blinking;
•select the solution temperature value by using the arrows;
confirm by pressing DATA/ENTER: the display stops blinking, and the temperature displayed is
used for compensation.
•To change the unit of measurement between °C and °F, it is necessary to press twice the °C/°F
key.
4.6 CALIBRATION OF THE PROBE
The probe calibration can be carried out on one, two or three points using the standard solutions
automatically detected by the instrument (automatic calibration) or other solutions with known
value (manual calibration).
The CAL symbol will blink when the cell constant is modified using the menu (please see the
description of the K_CELL item, chapter 3).
4.6.1 Automatic calibration of conductivity using memorized buffer solutions
The instrument can recognize four standard calibration solutions:
•0.001 Molar KCl solution (147μS/cm @25°C),
•0.01 Molar KCl solution (1413μS/cm @25°C),
•0.1 Molar KCl solution (12880μS/cm @25°C),
•1 Molar KCl solution (111800μS/cm @25°C),
Using one of these solutions, the calibration is automatic; the procedure can be repeated with one of
the remaining standard solutions, up to a maximum of four different points.
The manual calibration is possible with a different conductivity solution from that used in the
automatic calibration.
The solution temperature for the automatic calibration must be between 15°C and 35°C: if
the solution is under 15°C, the solution is compensated at 15°C. When over 35°C, the solution
is compensated at 35°C.

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1. Turn the instrument on with the ON/OFF key.
2. Set the probe's cell constant by selecting it from the admitted values: 0.1, 0.7, 1.0 or 10.0
3. Dip the conductivity meter cell in the calibration solution until the electrodes are covered with
liquid.
4. Stir the probe lightly to remove any possible air inside the measurement cell.
5. If the conductivity probe is not fitted with temperature sensor:
•press °C/°F;
•Enter the sample solution temperature value manually using the and arrows (manual
setting of temperature).
•Confirm by pressing DATA/ENTER.
6. Press the CAL key. The unit of measurement (μS/cm or mS/cm) appears on the comment line.
The central line shows the solution conductivity value at the measured temperature, or if the
probe is not present, at the manually-set temperature. In the lower line, the closest temperature
compensated standard buffer value.
If the measurement is in TDS, or resistivity, by pressing CAL, the instrument goes
automatically into conductivity calibration mode.
7. Press DATA/ENTER to confirm the displayed value. The cell constant nominal value (KCELL)
and the set temperature coefficient αTare displayed. Pressed repeatedly the DATA/ENTER key
allows the calibration on the point to be repeated, for example, in order to obtain a more stable
value.
8. To end the probe calibration, press χ/TDS/ESC. If on the other hand you wish to perform
another calibration on a different buffer, repeat the calibration procedure from point 3.
9. Rinse the probe with water. If you are then going to perform low conductivity measurements, we
recommend rinsing the probe using distilled or bidistilled water.
The instrument is calibrated and ready for use.
4.6.2 Manual calibration of conductivity using non memorized buffer solutions
Manual calibration is possible at any calibration solution and temperature if it is within the
instrument measurement limits and provided that you know the solution's conductivity at the
temperature at which the calibration is performed. Proceed as follows:
1. Turn the instrument on with the ON/OFF key.
2. Set the probe's cell constant by selecting it from the admitted values: 0.1, 0.7, 1.0 or 10.0
3. Dip the conductivity meter cell into a known conductivity solution until the electrodes are
covered with liquid.
4. Stir the probe lightly to remove any possible air inside the measurement cell.
5. Press °C/°F KEY, and then DATA to access the menu, press DATA until the item ALPH
appears. The temperature coefficient αTis displayed. Note down the value displayed as it must
be set again at the end of the procedure. Set the value to 0.00. This excludes the temperature
compensation during the conductivity measurement.

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6. According to the temperature detected, determine the calibration solution conductivity using
the table specifying the conductivity according to temperature.
7. Select the conductivity measurement by pressing χ/TDS/ESC.
8. Press the CAL key. The CAL symbol is turned on. The unit of measurement (μS/cm or mS/cm)
appears on the comment line. If the calibration solution conductivity is sufficiently close (-30%
to +50%) to one of the solutions used for calibration, the secondary line displays the value.
Otherwise it displays the calculated value according to current settings. In the central line the
solution conductivity value is indicated according to the cell constant current settings.
9. Use the arrows to select the conductivity value determined at point 5 and confirm using
DATA/ENTER. If the ERR indication appears, see the note below.
10. The cell constant nominal value (K_CELL) and the temperature coefficient αTset to 0 are
displayed. Pressed repeatedly the DATA/ENTER key allows the calibration on the point to be
repeated, for example, in order to obtain a more stable value.
11. To end the probe calibration, press χ/TDS/ESC.
12. Go back to the MENU and select ALPH: re-enter the temperature coefficient as it was before
the calibration.
13. Rinse the probe with water. If you are then going to perform low conductivity measurements,
we recommend rinsing the probe using distilled or bidistilled water.
The instrument is now calibrated and ready for use.
NOTES:
•Without having pressed DATA/ENTER at all, the calibration is interrupted by pressing
χ/TDS/ESC; the previous values will continue to be used.
•Upon confirming the calibration by using DATA/ENTER, the instrument checks that the
correction to the conductivity does not exceed the 70% or 150% limits of the theoretical value. If
the calibration is rejected because it is considered to be excessively corrupted, the CAL ERR
message will appear, followed by a long beep. The instrument remains in calibration mode and
maintains the previous calibration values.
•The most frequent causes of error are due to the probe malfunctioning (deposits, dirt,…) or to
the standard solutions deterioration (bad preservation conditions, alteration due to pollution with
different conductivity solutions,…).
•If the measurement is in resistivity, or TDS, on the pressing of CAL, the instrument goes
automatically in conductivity calibration.

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4.6.3 Table of buffer solution at 147μS/cm, 1413μS/cm, 12.88mS/cm and 111.8mS/cm
The table reports, below, the buffer solutions automatically detected by the instrument according to
temperature.
°C µS/cm µS/cm mS/cm mS/cm °C µS/cm µS/cm mS/cm mS/cm
15.0 121 1147
10.48 92.5 26.0 150 1440 13.13 113.8
16.0 124 1173 10.72 94.4 27.0 153 1467 13.37 115.7
17.0 126 1199 10.95 96.3 28.0 157 1494 13.62 117.7
18.0 128 1225 11.19 98.2 29.0 161 1521 13.87 119.8
19.0 130 1251 11.43 100.1 30.0 164 1548 14.12 121.9
20.0 133 1278 11.67 102.1 31.0 168 1581 14.37 124.0
21.0 136 1305 11.91 104.0 32.0 172 1609 14.62 126.1
22.0 138 1332 12.15 105.9 33.0 177 1638 14.88 128.3
23.0 141 1359 12.39 107.9 34.0 181 1667 15.13 130.5
24.0 144 1386 12.64 109.8 35.0 186 1696 15.39 132.8
25.0 147 1413 12.88 111.8
4.7 DIRECT INPUT INTO Pt100 AND Pt1000 TEMPERATURE PROBES
The instrument accepts the input of Platinum temperature probes with resistances of 100Ω(Pt100)
and 1000Ω(Pt1000).
The Pt100 are connected to 4 wires, the Pt1000 to 2 wires; the excitation current was chosen in
order to minimize the sensor self-heating effects.
The 4 wire and 2 wire probes with direct input are checked for conformity with class A
tolerance according to norm IEC751 - BS1904 - DIN43760.
The temperature probes are automatically detected by the instrument (please see the description of
the Probe Type menu item, chapter 3).
The °C or °F unit of measurement can be chosen for display using the °C/°F/MENU key.
4.7.1 Temperature measurement
The temperature measurement by immersion is carried out by inserting the probe in the liquid for at
least 60 mm; the sensor is housed in the end part of the probe.
In the temperature measurement by penetration the probe tip must be inserted to a depth of at least
60 mm, the sensor is housed in the end part of the probe.
NOTE: when measuring the temperature on frozen blocks it is convenient to use a mechanical tool
to bore a cavity in which to insert the probe tip.
In order to perform a correct contact measurement, the measurement surface must be even and
smooth, and the probe must be perpendicular to the measurement plane.
So as to obtain the correct measurement, the insertion of a drop of oil or heat-conductive
paste between the surface and the probe is useful (do not use water or solvents). This method
also improves the response time.

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4.7.2 Connecting the TP47 connector
All probes produced by Delta Ohm are provided with a connector.
The HD2306.0 instrument also work with direct 4 wire Pt100, and 2 wire Pt1000 probes
manufactured by other producers: for the instrument connection is prescribed the TP47 connector to
which the probe's wires should be welded.
The instructions to connect the Platinum or Nickel probe to the TP47 module are provided below.
The TP47 module is supplied complete with fairlead and gasket for 5 mm maximum diameter
cables. Do the following to open the module and connect a probe:
1. unscrew the fairlead;
2. extract the gasket;
3. remove the label using a cutter;
4. unscrew the ring on the opposite side as illustrated in the figure:
5. open the two module shells: the printed circuit to which the probe must be connected is
housed inside. On the left there are the 1…4 points on which the sensor wires must be
welded. The JP1…JP4 jumpers are in the center of the board. These must be closed with a
tin bead for some type of sensors:
1
2
3
4
Pt100 3 wires
Pt1000
Ni1000
Not Used
Caution! Before welding, pass the probe cable through the fairlead and gasket.
6. Weld the wires as shown in the table:
Sensor Board connection Jumper to close
Pt100 4 wires
4JP4
3JP3
1JP1
2JP2
Pt100
4 wires
None
Pt1000 2 wires
JP4
4
JP3
3
JP1
1
JP22
Pt1000
2 wires
None

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The Pt100 and Pt1000 sensors can also be welded directly on the connector's pins, without using
the TP47 board , as reported in the following table:
Sensor Direct connection to the connector Jumper
Pt100 4 wires
Pt100
Connector's internal view from the TP47 module
None
Pt1000 2 wires
Pt1000
Connector's internal view from the TP47 module
Jumper between pins 6
and 7
Jumper between pins 3
and 8
The wires coming from the conductivity/Pt100 temperature combined probe are welded directly on
the connector as reported in the following table.
Sensor Direct connection to the connector Jumper
2-electrode
conductivity
probe
Pt100
temperature
sensor
Pt100
Connector's internal view from the TP47 module
Jumper between pins 1
and 4
Jumper between pins 2
and 5
4-electrode
conductivity
probe
Pt100
temperature
sensor
Pt100
Connector's internal view from the TP47 module
None

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Ensure the welds are clean and perfect.
7. Once the welding operation is complete, close the two shells;
8. insert the gasket in the module;
9. screw the fairlead and the ring. Make sure the cable is not twisted while you are screwing
the fairlead. Now the probe is ready.

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5. WARNINGS
1. Do not expose the probes to gases or liquids that could corrode the material of the sensor or the
probe itself. Clean the probe carefully after each measurement.
2. Do not bend the probe connectors or force them upward or downward.
3. Do not bend or force the contacts when inserting the probe connector into the instrument.
4. Do not bend, deform or drop the probes, as this could cause irreparable damage.
5. Always select the most suitable probe for your application.
6. Do not use probes in presence of corrosive gases or liquids. The sensor container is made of
AISI 316 stainless steel, while the contact probe container is made from AISI 316 stainless steel
plus silver. Avoid contact between the probe surface and any sticky surface or product that
could corrode or damage it.
7. Above 400°C and below –40°C, avoid violent blows or thermal shocks to Platinum temperature
probes as this could cause irreparable damage.
8. To obtain reliable measurements, temperature variations that are too rapid must be avoided.
9. Temperature probes for surface measurements (contact probes) must be held perpendicular
against the surface. Apply oil or heat-conductive paste between the surface and the probe in
order to improve contact and reduce reading time. Whatever you do, do not use water or solvent
for this purpose. A contact measurement is always very hard to perform. It has high levels of
uncertainty and depends on the ability of the operator.
10. Temperature measurements on non-metal surfaces usually require a great deal of time due to the
low heat conductivity of non-metal materials.
11. Probes are not insulated from their external casing; be very careful not to come into contact with
live parts (above 48V). This could be extremely dangerous for the instrument as well as
for the operator, who could be electrocuted.
12. Avoid taking measurements in presence of high frequency sources, microwave ovens or large
magnetic fields; results may not be very reliable.
13. Clean the probe carefully after use.
14. The instrument is water resistant and IP67, but should not be immersed in water. The probe
connectors must be fitted with sealing gaskets. Should the instrument fall into the water, check
for any water infiltration. Gently handle the instrument in such a way as to prevent any water
infiltration from the connectors' side.