Delta OHM HD 9213-R1 User manual

HD 9213-R1
INSTRUCTION MANUAL

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HD 9213-R1

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HD 9213-R1
ENGLISH
MICROPROCESSOR CONDUCTIVITY
METER - THERMOMETER

1LCD Display
2Battery symbol
3Symbol indicating that the reading is in milliSiemens
4Symbol indicating that the reading is in microSiemens
5Key for selecting temperature reading in °C or °F
6Key for enabling the calibration function
7Key that increases the value to be set during the para-
meter setting phase
8Symbol indicating that the temperature reading is in °F
9Symbol indicating that the temperature reading is in °C
10 ON/OFF key for switching the instrument on and off
11 Key for selecting conductivity measurement
12 Key that decreases the value to be set during the para-
meter setting phase
13 Connector for the input of the conductivity and tempera-
ture probes, DIN 45326 8-pole male connector
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ON
OFF
RESET
ON
OFF
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Symbols lit
besides the numbers
Key Description
All the symbols are lit for
a few seconds after swit-
ching on
The battery symbol
flashes
K
Switches the instrument on and off.
The instrument switches itself off
automatically about 8 minutes after
the ON/OFF key has been pressed.
It is provided with an auto power off
function.
If the °C/°F key is held down simul-
taneously with the ON/OFF key
when switching on, the AUTO
POWER OFF function is disabled
and power is supplied without inter-
ruption. To switch off, press the
ON/OFF key. The battery symbol
flashes during this function.
When switching on, one of the
three messages appears after all
the symbols. The message that
appears indicates for what type of
calibration the instrument is set, or
what type was set previously.
Next appears one of the following
messages. The message that
appears indicates for what cell con-
stant (0.1 - 1.0 - 10), if any, the
instrument is set, or what constant
was set previously.
+

°C
°F

CAL
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Symbols lit
besides the numbers
Key Description
Key for selecting the temperature
reading in °C or °F.
The t symbol indicates the unit
chosen.
When used in combination with
others, the key also carries out
other functions.
When this key is pressed, if a probe
for conductivity measurement is
connected, the instrument measu-
res the conductivity of the liquid
being tested, giving a reading that
may be expressed in µS or in mS.
When used in combination with
others, the key also carries out
other functions.
When pressed during conductivity
measurement, this key enables the
automatic or manual calibration
function.
These keys increase 1 or decrease
2 the value indicated on the
display when pressed during auto-
matic or manual calibration, setting
of the cell constant factor, setting of
the reference temperature of the
measurement, setting of the tempe-
rature compensation value, or cali-
bration of the instrument.
µSmS°F°C
µSmS°F°C
µSmS°F°C
µSmS°F°C

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GENERAL INFORMATION
The HD 9213-R1 is normally supplied with the combined 4-electrode and
temperature probe SPT13.
The cell measurement area is bounded by a Pocan tube. A positioning
key, directs correctly the insertion of the tube into the probe. To clean the
probe, pull the tube along the probe axle. It is not possible to take mea-
surements without this tube.
The instrument may be fitted with 2-electrode conductivity probes with cell
constant 0.1 - 1 - 10; they may also be fitted with temperature measuring
probes of the series TP 9.. in various configurations and degrees of preci-
sion.
FUNCTIONS
1 - AUTO POWER OFF DISABLE
To disable the automatic cut-out function, proceed as follows: switch on
the instrument with the ON/OFF key, holding down the °C/°F key until
all the symbols disappear, then release the °C/°F key. The K symbol
flashes.
2 - REFERENCE TEMPERATURE 20°C or 25°C
To set the reference temperature, proceed as follows: switch on the
instrument with the ON/OFF key, holding down the CAL key until all the
symbols disappear, then release the CAL key. Using the 1 or 2 key,
set the desired value r20 or r25, which stand for 20°C or 25°C. To quit
this routine, press the key.
3 - SELECTING THE CELL CONSTANT
To select the cell constant for probes with 2 electrodes, proceed as fol-
lows: switch on the instrument with the ON/OFF key, holding down the
key until all the symbols disappear, then release the key. One of
the messages c 0.1, c 1.0 or c 10 appears on the display. Using the 1
and 2 keys, set the desired cell constant c 0.1, c 1.0 or c 10 which

stand for cell constant 0.1 or 1 or 10.
To quit this routine, press the  key.
CALIBRATION CODES OF THE TEMPERATURE PROBES
The instrument has 5 codes, 3 of which are used for calling calibrations
while 2 are calibration procedures. They are identified as follows:
C1: The instrument operates with the original calibration performed in the
Delta Ohm workshop. It cannot be altered.
C2: The instrument operates with temperature calibration of the instrument
alone, performed with a suitable simulator.
C3: The instrument takes measurements and operates with a certain tem-
perature probe; the calibration of instrument and probe is the one that
gives the most precise results.
C6: Procedure for calibrating the temperature section of the instrument,
performed with a suitable calibrator.
C8: Procedure for calibrating the instrument together with a certain tempe-
rature probe. The two points on the scale are calibrated with a calibra-
tion furnace.
PROCEDURE FOR ENABLING AND CALLING ONE OF
THE THREE STORED CALIBRATIONS
To select codes C1, C2 or C3, proceed as follows: switch on the instru-
ment with the ON/OFF key, holding down the key and the CAL key until
all the symbols disappear. The message CAL then appears, followed by
00; using the 1 and 2 keys, set the desired code, that is C1, C2 or C3.
Confirm by pressing the CAL key. The K symbol flashes and the CAL
message remains fixed for a few seconds; the instrument then switches off
and the procedure is complete.
PROCEDURE FOR CALIBRATING THE TEMPERATURE
SECTION OF THE INSTRUMENT AND FOR STORING
CALIBRATION
To calibrate the instrument temperature code C6, proceed as follows:
switch on the instrument with the ON/OFF key, holding down the key
and the CAL key until all the symbols disappear. The message CAL then
appears, followed by 00; using the 1 and 2 keys, set the code C6.
Press the CAL key.
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Simulate 0°C at the instrument input with a suitable simulator; using the 1
and 2 keys, set on the display the correct value which corresponds to the
first calibration point.
Next simulate the second calibration point and set the correct value on the
display using the 1 and 2 keys. Press the CAL key to store the calibration
performed.
PROCEDURE FOR CALIBRATING THE INSTRUMENT
WITH ITS TEMPERATURE PROBE AND FOR STORING
THE DATA
To calibrate the instrument with its temperature probe, code C8, proceed
as follows: switch on the instrument with the ON/OFF key, holding down
the key and the CAL key until all the symbols disappear. The message
CAL then appears, followed by 00; using the 1 and 2 keys, set the code
C8.
Connect the desired temperature probe to the instrument; insert it in the
calibration furnace at 0°C corresponding to the first calibration point, then
set the correct value on the display using the 1 and 2 keys.
Insert the temperature probe in the calibration furnace for the second cali-
bration point, then set the correct value corresponding to the second cali-
bration point on the display, using the 1 and 2 keys.
Press the CAL key to store the calibration performed.
CALIBRATING THE CONDUCTIVITY SECTION OF THE
INSTRUMENT
The instrument is able to recognize two standard calibration solutions: a
0.1 - mole solution of KCl and a 0.01 - mole solution of KCl. These solu-
tions are on sale in specialized shops or they may be prepared by fol-
lowing the procedures given below. Calibration is automatic when using
one of these two solutions.
Manual calibration is possible using a standard solution with a diffe-
rent conductivity from the solution used in automatic calibration.
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PREPARATION OF STANDARD CALIBRATION
SOLUTIONS
Dry the potassium chloride (KCl) at 105...120°C (221...248°F) for two
hours. For a 1-mole solution, dissolve 74.555 g KCl in one litre of demine-
ralized water with conductivity less than 3 µS/cm. For a 0.1-mole solution,
dissolve 7.456 g KCl in one litre of demineralized water with conductivity
less than 1 µS/cm. For a 0.01-mole solution, add 100 millilitres of 0.1-mole
solution to 900 millilitres of demineralized water with conductivity less than
1 µS/cm.
c0.01 M 0.1 M 1 M
T18°C 1.225 mS/cm 11.19 mS/cm 98.24 mS/cm
19°C 1.251 mS/cm 11.43 mS/cm 100.16 mS/cm
20°C 1.278 mS/cm 11.67 mS/cm 102.09 mS/cm
21°C 1.305 mS/cm 11.91 mS/cm 104.02 mS/cm
22°C 1.332 mS/cm 12.15 mS/cm 105.94 mS/cm
23°C 1.359 mS/cm 12.39 mS/cm 107.89 mS/cm
24°C 1.386 mS/cm 12.64 mS/cm 109.84 mS/cm
25°C 1.413 mS/cm 12.88 mS/cm 111.80 mS/cm
AUTOMATIC CALIBRATION
Automatic calibration is possible with a 0.1-mole (or 0.01-mole) solution of
KCl. The temperature of the solution must be between 15°C (59°F) and
30°C (86°F), otherwise the error signal “E3” appears.
a) Switch on the instrument by pressing the ON/OFF key.
b) Immerse the conductimetry cell in the sample solution so that the elec-
trodes are covered.
c) Shake the probe gently so that any air inside it will escape.
d) Press the CAL key. The conductivity value of the solution at the probe
temperature appears on the display. For example 1278 µS at 20°C
(68°F) and the µS (or mS) symbol flashes.
e) Press the CAL key again to confirm the value displayed (or adjust this
value with the 1 and 2 keys before pressing CAL again). The µS (or
mS) symbol stops flashing.
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Note: when leaving calibration mode the value on the display may increase
or decrease. This happens only if the temperature of the liquid is different
from 20°C (25°C) (which is the temperature at which the conductivity values
are normalized). In fact, when the temperature is different from 20°C (25°C)
the instrument indicates the conductivity value with the temperature com-
pensation made according to the αTcoefficient, set by the user, which may
be considerably different from the value of the calibration solution.
f) Rinse the probe in water. If measurements are later made at low con-
ductivity, we advise rinsing it in distilled or bidistilled water.
At this point the instrument is calibrated and ready for use.
MANUAL CALIBRATION
Manual calibration is possible using solutions with any conductivity. Howe-
ver it is necessary to know the conductivity of the solution at the tempera-
ture at which calibration is to be carried out. Follow these instructions:
a) Immerse the conductimetry cell in the solution with known conductivity
so that the electrodes are covered with liquid. Switch on the instrument
by pressing the ON/OFF key.
b) Press the αTkey. The temperature coefficient used for calculating the
temperature compensation in conductivity measurements is displayed.
Using the 2 key, bring the value displayed to 0.00. In this way the tem-
perature compensation in conductivity measurement is excluded.
c) Take the temperature reading by pressing the °C/°F key. On the basis of
the temperature determine the conductivity of the calibration solution, for
example by looking it up in a table that indicates conductivity as a func-
tion of temperature.
d) Press the  key. Press the CAL key. The µS (or mS) symbol flashes. If
the conductivity of the calibration solution is close to that used in auto-
matic calibration, the instrument proposes this value. Using the 1 and
2 keys, set the conductivity value determined at point c. If the conducti-
vity of the calibration solution is very different from the one used in auto-
matic calibration, “E1” (slope >150% of the rated value) or “E2” (slope
<30% of the rated value) is displayed. In both cases it is sufficient to
press the 1 or 2 key to cancel the error signal. Using the same keys,
set the conductivity value determined at point c.
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e) Press the CAL key again to confirm the value displayed. The µS (or mS)
symbol stops flashing. Rinse the probe with water. If measurements
are later made at low conductivity, we advise rinsing it in distilled
or, better, bidistilled water.
At this point the instrument is calibrated and ready for use.
TEMPERATURE COMPENSATION
The temperature coefficient αTis the percentage measurement of the varia-
tion of conductivity with temperature and is expressed in %/°C (or %/°F).
The electric conductivity of a metal decreases as the temperature increases,
while it increases in a liquid. There therefore arises the problem that the
conductivity of two liquids cannot be directly compared if the measurement
has not been made at the same standard reference temperature, which in
chemical measurements is 20°C (25°C). If the measurement is taken at a
temperature different from 20°C (25°C), an approximate assessment of the
conductivity of the liquid at 20°C (25°C) may be obtained by means of tem-
perature compensation, defined by the following formula (see also fig. 3.1):
where: = temperature expressed in °C
= conductivity at temperature (°C)
20 = conductivity at 20°C (25°C)
αT20 = temperature coefficient expressed in %/°C
Unfortunately the formula does not give good results if the temperature is
appreciably different from 20°C (25°C) because αTis not constant, but a
non-linear function of the temperature and the conductivity. Also, it is not
generally known before taking the measurement, unless it can be found on
tables referring to the liquid to be examined. αTmay be experimentally
determined by taking two measurements, one at 20°C (25°C) and another
at the temperature , having previously excluded temperature compensa-
tion (in the HD 9213-R1 this may be done by setting αTat 0.00, see the
next paragraph). The formula for calculating αTis the following:
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= 20 αT
100
1 + (- 20)
100
20
(- 20)
αTx
=- 20

For the definition of the variables see the figure
Definition of the temperature coefficient
In the HD 9213-R1 temperature compensation is automatic and therefore it
is sufficient to set the temperature coefficient αTof the liquid with the fol-
lowing procedure:
SETTING THE TEMPERATURE COEFFICIENT αT
To set the temperature coefficient αT, proceed as follows:
Switch on the instrument by pressing the ON/OFF key, choose the measu-
ring unit °C or °F, then press the CAL and °C/°F keys simultaneously;
using the 1 and 2 keys, set the desired coefficient value between 0.00
and 4.00. Then press the °C/°F key to store the chosen value of αT. The
value of αTmay be set independently in either °C or °F.
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


20
20 



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Concentra- Conductivity
Substance tion 104S•cm-1
NaOH 5 1969 2.01
(15°C) 10 3124 2.17
15 3463 2.49
20 3270 2.99
30 2022 4.50
40 1164 6.48
KOH 25 .2 5403 2.09
(15°C) 29 .4 5434 2.21
33 .6 5221 2.36
42 .0 4212 2.83
NH30. 10 2 .51 2.46
(15°C) 1. 60 8 .67 2.38
4. 01 10 .95 2.50
8. 03 10 .38 2.62
16. 15 6 .32 3.01
30. 5 1 .93 –
HF 1 .5 198 7.20
4 .8 593 6.66
HCI 24 .5 2832 5.83
5 3948 1.58
10 6302 1.56
20 7615 1.54
30 6620 1.52
40 5152 –
H2SO45 2085 1.21
10 3915 1.28
20 6527 1.45
40 6800 1.78
50 5405 1.93
60 3726 2.13
80 1105 3.49
100 .14 187 0.30
HNO36 .2 3123 1.47
12. 4 5418 1.42
31 .0 7819 1.39
49 .6 6341 1.57
62 .0 4964 1.57
H3PO410 566 1.04
(15°C) 20 1129 1.14
40 2070 1.50
45 2087 1.61
50 2073 1.74
NaCl 5 676 2.17
10 1211 2.14
15 1642 2.12
20 1957 2.16
25 2135 2.27
Concentra- Conductivity
Substance tion 104S•cm-1
Na2SO45 409 2.36
10 687 2.49
15 886 2.56
Na2CO35 456 2.52
10 705 2.71
15 836 2.94
KCl 5 690 2.01
10 1359 1.88
15 2020 1.79
20 2677 1.68
21 2810 1.66
KBr 5 465 2.06
(15°C) 10 928 1.94
20 1907 1.77
KCN 3 .25 507 2.07
6 .5 1026 1.93
NH4Cl 5 918 1.98
10 1776 1.86
15 2586 1.71
20 3365 1.61
25 4025 1.54
(NH4)2SO4 5 552 2.15
(15°C) 10 1010 2.03
20 1779 1.93
30 2292 1.91
NH4NO35 590 2.03
(15°C) 10 1117 1.94
30 2841 1.68
50 3622 1.56
CuSO42 .5 109 2.13
5 189 2.16
10 320 2.18
15 421 2.31
CH3COOH 15.84–
10 15 .26 1.69
15 16.19 1.74
20 16 .05 1.79
30 14 .01 1.86
60 4 .56 2.06
Temperature
coefficient
%/°C
Temperature
coefficient
%/°C
Conductivity and corresponding temperature coefficients of certain substances (25°C)

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HOW TO MEASURE CONDUCTIVITY
a) Connect the connector of the conductimetry cell to the instrument
paying attention to the polarization mark. Immerse the probe in the
solution so that the electrodes are covered. Shake the probe gently
so that any air inside it will escape.
b) Switch on the instrument by pressing the ON/OFF key. If the instrument
has not been calibrated, proceed to do so.
c) Set the temperature coefficient.
d) Press the key to measure the conductivity of the liquid with reference
to the temperature of 20°C or 25°C. If you wish to measure the absolute
conductivity (that is without temperature compensation) just set αTat
0.00.
e) After use rinse the probe with clean or, better, distilled water.
MEASURING CONDUCTIVITY WITH 2-ELECTRODE
PROBES
The instrument may be fitted with 2-electrode probes with or without a
Pt100 temperature sensor and cell constant K 0.1, 1 or 10 • cm-1.
The measuring range of these cells is indicated in the diagram below:
1 10 100 10 100 1000
µS / cm mS / cm
0.1
K=10
K=1.0
K=0.1

APPLICATIONS OF CONDUCTIVITY MEASUREMENTS
It must always be remembered that the conductivity of a liquid is proportio-
nal to the total amount of dissolved substances and not to one specific
substance. Despite this there are many applications of conductivity, espe-
cially for quality controls.
CHECKING IMPURITIES IN WATER
The most frequent applications are in the demineralization of water, by
distillation, ionic exchange or inverse osmosis. Of course it is not possible
to measure impurities that do not contribute to conductivity, such as sand,
oil, micro-organisms, etc. Good distilled water should have a conductivity
of less than a few µS.
An interesting application is the determination of impurities in sugar. Sugar
is not an electrolyte and does not contribute to a variation of conductivity if
it is dissolved in demineralized water, but impurities do.
DETERMINING THE CONCENTRATION OF A SOLUTION
If there is only one electrolyte in a solution, its concentration may be deter-
mined by measuring the conductivity. For example, the graphs above show
the conductivity trend of a number of electrolytes as a function of concen-
tration. If the curve that gives the conductivity as a function of concentra-
tion shows a maximum value, the concentration cannot be determined for
certain because for a given conductivity value there are two concentration
values. In this case the solution must be dissolved so at so obtain a certain
value. If the solution contains more than one type of electrolyte, the con-
centration of the individual components cannot be determined unless parti-
cular conditions are present. For example, an acid or a strong base contri-
bute much more than a salt to the increase in conductivity. Typical exam-
ples: regulation of detergent in industrial washing, regulation of degreasing
baths, regulation of galvanic baths, checking milk, checking fertilizer in irri-
gation systems, etc.
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ENGLISH
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Conductivity of dilute solutions.
Conductivity of high concentration solutions.

CHECKING CONDUCTIVITY IN MULTI-ELECTROLYTE
SOLUTIONS
A conductimetry control often allows the chemical-physical variation of a
solution to be detected. In oceanography the total saline content may be
determined by means of conductivity measurements. In lake or river water
a variation in conductivity is often the sign of pollution due to industrial
waste water. The hardness of the feeding water for boilers, cooling towers,
steam generators, etc. may be determined approximately by means of
conductivity measurements. (In Italy it is sufficient to multiply the conducti-
vity at 20°C by 0.7 to obtain the quantity of equivalent salinity expressed in
ppm of CaCO3). In the food industry the concentration of various saline
solutions for preserving foodstuffs may be determined by measuring con-
ductivity.
SALINITY OF THE SOIL
It is a known fact that for different types of plants, flowers and cereals there
are optimum soil salinity values. Conductivity measuring allows indirect
determination of the salinity of the soil.
The method adopted by the Italian Society of Science of the Soil is the fol-
lowing:
Take a sample of soil, dry it in the air and riddle it at 2 mm. Dissolve it in 5
times its volume of demineralized water. Stir for about 30 minutes. Let the
liquid rest for a few minutes and take the measurement with an electrode
immersed in the liquid just over the soil sediment. The conductivity found
must be expressed in µS/cm at the temperature of 20°C. The salinity of the
soil is calculated with the formula:
where: S = salinity of the soil in gr/100 of soil
20= conductivity expressed in µS at 20°C
The measured values allow the regulation of the dose of fertilizer in the irri-
gation water.
ENGLISH
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0.32 • 20
S=1000

ERROR INDICATION
OL: Overload warning.
E1: The solution used for conductivity calibration is wrong because the
slope calculation gives a value >150% of the rated value.
E2: The solution used for conductivity calibration is wrong because the
slope calculation gives a value <30% of the rated value.
E3: The temperature of the calibration solution is not between 15°C
(59°F) and 30°C (86°F). Calibration is inadmissible outside this range.
ENGLISH
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(mS•cm-1)
102105
103106
104107
10 1040.1 1 10 100
0.1 1 10 100
Resistance (Ω•cm)
Conductivity (µS•cm-1)
Correspondence between electric resistance and conductivity

METHOD OF USE
*Ensure that the measuring area is not live. The instrument is not insula-
ted; during measurement with non-insulated probes ensure that it does
not come in contact with live surfaces with a voltage of more than 24V.
This could be dangerous for the instrument but especially for the opera-
tor who could receive an electric shock.
*Do not expose the probes to gases or liquids which could corrode the
material with which the probes are covered. Ensure that the type of
material with which the probe is made (POCAN - Alumina/Platinum) is
compatible with the environment in which the measurement is to be
taken.
*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.
*In order to obtain a reliable measurement, avoid too sudden variations in
temperature.
*Measurements on non metal surfaces require a great deal of time on
account of their low heat conductivity.
*Always clean the probe 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.
*Avoid taking measurements in the presence of high frequency sources,
microwaves or large magnetic fields, as the results would not be very
reliable.
LOW BATTERY WARNING AND BATTERY REPLACEMENT
If the battery voltage falls below a certain level, the H symbol appears on
the display. From that moment there remains about 1 hour autonomous
operation. The battery should be replaced as soon as possible, otherwise,
if the voltage falls even further, the data shown are no longer correct; the
battery symbol disappears. The battery used is an ordinary 9V zinc-carbon
battery, IEC6LF22.
ENGLISH
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