Hanna Instruments HI 8931, HI 8936, HI 8931A, HI 8936A, HI 8936AL Instruction Manual

Instruction Manual

HI 8931 • HI 8936 Series

HI943500 Series

Conductivity Process

Controllers and Transmitters

www.hannainst.com

32

Dear Customer,
Thank you for choosing a HANNA instruments® product.
Please read this instruction manual carefully before using the instru­ment.
This manual will provide you with all the necessary information for
correct use of the instruments, as well as a precise idea of thier
versatility in a wide range of applications.
If you need additional technical information, do not hesitate to e-mail
us at [e-mail]
These instruments are in compliance with the directives.

TABLE OF CONTENTS

Preliminary Examination ............................................................ 4

General Description .................................................................... 4

Functional Description HI 8931 & HI 943500 ............................ 6

Functional Description HI 8936 ................................................ 10

Conductivity Probes .................................................................. 13

Specifications HI 8931 & HI 943500 ....................................... 15

Specifications HI 8936 ............................................................. 16

Connections .............................................................................. 17

Operational Guide ................................................................... 25

Calibration Procedure of HI 8931 & HI 8936 with HI 7635 .... 31

Calibration Procedure of HI 8931 & HI 8936 with HI 7638 .... 35

Calibration Procedure of HI 943500 with HI 7638................... 39

Conductivity Versus Temperature Chart ..................................... 41

Diagnostic Tests ........................................................................ 42

Installation Examples ............................................................... 44

Probe Maintenance and Cleaning ............................................ 46

Accessories ................................................................................ 47

Warranty................................................................................. 49

CE Declaration of Conformity ..................................................... 50

54

Four models with different measurement ranges are available to suit
any application needs:

• HI8931A / HI 943500A / HI8936A / HI8936AL

from 0.0 to 199.9 mS/cm

• HI8931B / HI 943500B / HI 8936B / HI 8936BL

from 0.00 to 19.99 mS/cm

• HI 8931C / HI 943500C / HI8936C / HI8936CL

from 0 to 1999 μS/cm

• HI 8931D / HI 943500D / HI8936D / HI8936DL

from 0.0 to 199.9 μS/cm

Other features include: recorder output in 0-20 mA or 4-20 mA
configuration; LED indicators (for HI 8931 and HI 943500) which
identify whether the controller is in operation mode or selection mode.

Each instrument of the HI 8931 and HI 943500 series, is supplied
with a plastic front cover and two mounting brackets. Power cables
are not included.

PRELIMINARY EXAMINATION

GENERAL DESCRIPTION

Remove the instrument from the packing material and examine it
carefully to make sure that no damage has occurred during shipping.
If there is any noticeable damage, notify your dealer.

Each model is supplied complete with:

• Mounting brackets (not for HI 8936 series)

• Transparent splsh-proof cover (not for HI 8936 series)

• Instruction manual

Note: Save all packing materials until you are sure that the

instrument functions correctly. All defective items must be
returned in the original packing materials together with
the supplied accessories.

The HI 8931 and HI 943500 are panel-mounted conductivity control­lers designed for simplicity of use in a wide range of industrial process
applications.

The instruments are designed with a standard DIN panel mount with
membrane keypads and large LCD on the front, and provide a series
of auto-diagnostic functions.

Probes, power supply, contacts and recorders are connected on the
rear panel through screw terminals.

Using HI 8931 in conjunction with a 4-20 mA output transmitter
(HI 8936 or HI 8936L series) will assure you of a strong, interference­free signal at distances up to 300 meters (1000').

For in-line applications use the HI 7635 probe, while for tanks the
HI 7638 with external threads is recommended. These probes are
provided with built-in NTC sensor for temperature compensated
conductivity measurements. The probe cable length is 3 meters (10').

HI 943500 features a direct connection up to 20 m (67'), without
intermediate amplifiers, to the conductivity probe HI 7638 with DIN
connector and automatic temperature compensation.

76

Unplug the instrument from power supply before
replacing the fuse.

REAR PANEL OF HI 8931 SERIES

1. POWER OUTPUT terminals (+20 V and COM) for connec-

tion to a conductivity transmitter (HI 8936)

2. mA INPUT from a conductivity transmitter

3. mA OUTPUT terminals for connection to a recorder

4. SET SELECT terminals for reverse control operation

5. SET terminals for connection to a dosing pump

6. ALARM terminals for connection to an external alarm device

7. Power supply terminals

8. Fuse holder

FUNCTIONAL DESCRIPTION

HI 8931 & HI 943500

KEYPAD
MEASURE To read measurements and enable diagnostic tests
ΔAL To display set tolerance of the alarm
SET To set working point
TEST SLOPE Diagnostic function
TEST OFFSET Diagnostic function

When a key is pressed, the corresponding LED lights up to indicate that
the function is active.

TRIMMERS
OFFSET For offset calibration

SLOPE For slope calibration
ΔAL To set the alarm tolerance
COARSE To coarsely adjust the set point
SET FINE To finely adjust the set point

LEDS
SET ON To indicate that the dosage is active

ALARM To indicate an alarm condition

98

MECHANICAL DIMENSIONS
OF HI 8931 AND HI 943500

Front view of the panel-mounted unit

These dimensions show the cutout size for the installation.

Side view of the panel-mounted unit

Adjustable location brackets (supplied with the meter) allow the indicator
to slide into the cutout and will hold the unit securely in place. 190 mm
(7.50") is the minimum amount of room required to install the indicator
with the cables connected.

190mm MIN

7.50"

135mm

5.31"

0.25/4mm

0.01/0.160"

144mm

5.67"

ADJUSTABLE
LOCATION
BRACKET

141mm

5.55"

144m

m

5.67

"

69mm

2.71"

72mm

2.83"

REAR PANEL OF HI 943500 SERIES

1. DIN connector for conductivity probe

2. mA OUTPUT terminals for connection to a recorder

3. SET SELECT terminals for reverse control operation

4. SET terminals for connection to a dosing pump

5. ALARM terminals for connection to an external alarm device

6. Power supply terminals

7. Fuse holder

Unplug the instrument from power supply before
replacing the fuse.

1110

SIDE VIEW OF HI 8936 SERIES

1. Top cover

2. Cable glands for wiring

FUNCTIONAL DESCRIPTION HI 8936

1. Back cover

2. Top cover

3. Liquid Crystal Display

4. Screws for fastening the top cover

HI 8936A
HI 8936B
HI 8936C
HI 8936D

HI 8936AL
HI 8936BL
HI 8936CL
HI 8936DL

1312

CONDUCTIVITY PROBES

73mm

2.87"

52mm

2.04"

1" NP

T

142mm

5.60"

HI 7635 In-line Conductivity Probe

HI 7635 is a one piece, molded conductivity probe with pipe threads

(1" NPT) at both ends.
This allows the probe to attach to an in-line system, and to be used

in conjunction with the HI 8936 conductivity transmitter.
The HI7635 uses a 4-ring potentiometric measuring method. This

method is highly accurate and requires very little maintenance.
The construction of the housing is rugged, fiber-reinforced polypropy-

lene.
The maximum working pressure of this unit is 5 bar (72.5 psi).
Do not use in systems where the temperature exceeds 80°C (176°F).

HI7635

MECHANICAL DIMENSIONS OF

HI 8936A, HI8936B, HI 8936C, HI 8936D

MECHANICAL DIMENSIONS OF

HI 8936AL, HI8936BL, HI8936CL, HI 8936DL

110m

m

4.33

"

100mm

3.94"

HI 8614

165mm

6.50"

155mm

6.10"

4 x 4.3mm

4 x 0.17"

90mm

3.54"

110m

m

4.33

"

100mm

3.94"

HI 8614L

165mm

6.50"

155mm

6.10"

90mm

3.54"

4 x 4.3mm

4 x 0.17"

126mm

5.00"

45mm

1.77"

24mm

0.94"

58mm

2.28"

1514

SPECIFICATIONS HI 8931 & HI 943500

0.0 to 199.9 mS/cm

0.00 to 19.99 mS/cm
0 to 1999 μS/cm

0.0 to 199.9 μS/cm
±2% of Full Scale

excluding probe error
±2.5% of Full Scale

±0.4 mA

HI 8936 A or AL (not included)
HI 8936 B or BL (not included)

HI 8936 C or CL (not included)

HI 8936 D or DL (not included)

------

HI 7635 for in-line applications or

HI 7638 for tank (not included)

Manual, 2 point, through

offset and slope trimmers

See transmitter HI 8936

Automatic, 0 to 60°C with ß=2%

4 to 20 mA (isolated)

Isolated, 2A, Max. 240V, resistive

load, 1,000,000 strokes

115 or 230 Vac ±10%

(user selectable); 50/60 Hz

-10 to 50°C (14 to 122°F); RH 95%
141 x 69 mm (5.6 x 2.7")

1 kg (2.2 lb.)

DIN 43 700, 144x72 mm (5.7x2.8"),

black anodized aluminum;

front and back with shockproof ABS

plastic, and transparent cover

Range
HI 8931A - HI 943500A
HI 8931B - HI 943500B
HI 8931C - HI 943500C
HI 8931D - HI 943500D
Accuracy
(@20°C/68°F)
Typical EMC

Deviation
4-20mA INPUT from
Transmitter
HI 8931A
HI 8931B
HI 8931C
HI 8931D

HI 943500
Conductivity Probe

Calibration

Temp. Compensation
HI 8931

HI 943500
Recorder Output

Set Point Relay and
Alarm Relay

Power Supply

Environment
Panel Cutout
Weight
Enclosure

HI7638 Tank Conductivity Probe

HI7638 conductivity probe combines the proven 4-ring potentiometric

method of measuring conductivity with the platinum sensor and
stainless steel external thread.

This method incorporates a series of four platinum rings into the probe
shaft and is highly accurate requiring very little maintenance.

The removable plastic cover resists the harmful effect of most chemicals
and can be unscrewed for quick and simple maintenance.

This probe can withstand temperatures of up to 120°C (248°F) and
pressure of up to 5 bar (72.5 psi).

This probe is supplied complete with a 7-pin DIN connector.

HI 7638

1716

CONNECTIONS

REAR CONNECTIONS FOR HI 8931

• Power Connection Terminals

4-screw-terminal-strip for connection
to a 3-wire power cable according to
the indicated voltage (115 or 230V).

• IN/OUT Transmitter

2 wires of the 4-core signal cable
from the conductivity transmitter
(HI8936) have to be connected to
the mA input terminals and the
other 2 wires to the "+20 V" and
"COM" while paying careful atten­tion to the polarity.

+20 V supply is the regulated DC supply required for the
operation of the external conductivity transmitter HI 8936.

• Set Contacts

Dosing pumps or other control equip­ment may be connected to the "SET"
(Max. 2A, 240 V) terminals. These
contacts act only as a "dry" switch
allowing electrical continuity, not as
a power supply.

SPECIFICATIONS HI 8936

0.0 to 199.9 mS/cm

0.00 to 19.99 mS/cm
0 to 1999 μS/cm

0.0 to 199.9 μS/cm
±2% of Full Scale

excluding probe error

±2% of Full Scale

±0.4 mA

HI 7635 for in-line applications or

HI 7638 for tank (not included)

Manual, 2 point, through

offset and slope trimmers

Fixed or automatic

from 0 to 50°C (32 to 122°F)

with ß=2%

4 to 20 mA not-isolated

max. 500 Ohm

12 to 30 Vdc
17 to 36 Vdc

IP 65

0 to 50°C (32 to 122°F);

RH max 95%

165 x 110 x 90 mm

(6.5 x 4.3 x 3.5")

1 kg (2.2 lb.)

Range
HI 8936 A/AL
HI 8936 B/BL
HI 8936 C/CL

HI 8936 D/DL
Accuracy
(@20°C/68°F)

Typical EMC
Deviation
Conductivity Probe

Calibration

Temperature
Compensation

Output

Power Supply
HI 8936 A/B/C/D
HI 8936 AL/BL/CL/DL

Protection
Environment

Dimensions

Weight

1918

TERMINAL BOARD CONNECTIONS FOR H8936

• Remove the 4 screws and the top cover of the HI 8936 conductivity

transmitter to obtain access to the terminal board connections.

• HI 8936 used in conjunction with HI 8931 controller

Use a PVC insulated 4-core cable to connect the transmitter to the
HI 8931 conductivity controller (see also page 25).

• Set Select

These contacts permit the activation
of a Set Contact relay when the
measured value is lower (connected
terminals) or higher (open termi­nals) than the user's set value. See
also page 28.

• +4-20 mA

These are the output terminals for connection to a recorder or other
control equipment.

The output current varies from 4 to 20 mA and is proportional to
the measured conductivity value.

• Alarm Contacts

During normal operation these termi­nals remain closed.

If the measured conductivity level is
not within the tolerance of the set
value, the alarm contact is open.
These contacts act only as a switch.
See also page 29.

2120

• Probe Connection

The conductivity probe is supplied
with a 3 m (10'), 6 core cable.
The cable is to be connected to the
terminals provided (see also page
24 for proper connection scheme of
HI 7635 and HI7638).

The 4-core cable has to be con­nected to the transmitter accord­ing to the label instructions on the
4-terminal strip.

The regulated D.C. supply required for the proper operation of the
transmitter is "+20 V", labeled "+20 V" and "COM". The current
(mA) output terminals are labeled "4-20 mA" and "COM".

The transmitter is protected against inversion of supply voltage.

• HI 8936 used in conjunction with an external power supply

Use 2 PVC insulated 2-core cables.

Connect a +20 Vdc power supply
directly to the terminals labeled
"+20 V" and "COM", paying care­ful attention to polarity (see also
page 24) or if necessary in series
with the receiving device.

The regulated DC supply required for the proper functioning of the
circuit is marked "+20 V" and "COM", and the transmitter current
output is indicated "4-20 mA" and "COM".

The transmitter is protected against inversion of supply voltage.

Max. current required: 40 mA.

• Use of an amplifier

The maximum permissible distance between the power supply unit
and the amplifier is 300 m (1000'). It is not necessary to use a
shielded cable.

2322

• Set

Dosing pumps or other control equipment may be connected to the
"SET" (Max. 2A, 240 V) terminals. These contacts act only as a
"dry" switch allowing electrical continuity, not as a power supply.

• Alarm Contacts

During normal operation these ter­minals remain closed.

If the measured conductivity level
is not within the tolerance of the
set value, the alarm contact is
open. These contacts act only as a
switch. See also page 29.

REAR CONNECTIONS FOR HI 943500

• Power Connection Terminals

4-screw-terminal-strip for connec­tion to a 3-wire power cable ac­cording to the indicated voltage
(115 or 230 V).

• DIN connector socket

For connection to the
HI 7638 conductivity
probe.

• + mA output -

The first and the second
terminals are the output
terminals for connection to
a recorder or other control
equipment. The output cur­rent varies from 4 to 20
mA and is proportional to
the measured conductivity
value.

• Set Select

These contacts permit the
activation of the Set Contact relay when the measured value is
lower (connected terminals) or higher (open terminals) than the
user's set value. See also page 28.

2524

INITIAL PREPARATION & INSTALLATION

Material needed:

• a 3-wire power cable (to connec the HI 8931 or HI 943500 to

the mains)

• a PVC insulated 4-core cable (to connect the HI 8931 to HI8936)

• rubber seals and a pipe sealant (for installation of HI 7635)

FOR HI 8931 AND HI 8936 ONLY

• Remove the 4 screws and the

top of the HI 8936 conductivity
transmitter.

• Connect the 2 wires connected to
the "4-20 mA" and "COM" ter­minals of the 4-core signal cable
from the HI 8936 to the termi­nals marked "mA input" paying
careful attention to polarity.
Connect the other 2 wires to the
"+20 V" and "COM" terminals,
while paying attention to the
polarity.

• Connect the 3-wire power cable
to the 4-screw terminal strip ac­cording to the voltage level as
indicated, and pay particular
attention to the correct live, earth
and neutral terminal connections.

OPERATIONAL GUIDE

CONDUCTIVITY PROBE CONNECTIONS

The connections for HI 7635
are color coded for easy in­stallation and are as fol­lows:

HI 7635 cable HI 8936 transmitter

Black or Grey NTC

Red or Pink SENSOR

Brown or Orange probe pin 1

Blue probe pin 2

White probe pin 3

Green or Yellow probe pin 4

The connections for HI 7638 are
as follows:

HI 7638 HI 8936 transmitter

#1 probe pin 1
#2 probe pin 2
#3 probe pin 3
#4 probe pin 4
#5 NTC
#6 SENSOR

Note: NTC & SENSOR are equivalent, and are both labeled

"SENSOR" on the HI 8936 conductivity transmitter.

connector

inside view

2726

• It is recommended to install the HI 7635 vertically. This is to
ensure that trapped air bubbles or turbulent flows cause minimal
interference to the measurement system. The maximum working
pressure of this unit is 5 bar (72.5 psi).

WARNING: Do not use when temperature exceeds 80°C (176°F).

• The HI 7638 process conductivity probe is also
supplied with a 3 m (10') cable. The 6-core
cable of this probe is connected to the HI 8936
process conductivity transmitter as shown.

The DIN connector has to be removed when this probe is used in
conjunction with an HI8936 transmitter. See page 24 for the
proper connection scheme.

FOR HI 943500 ONLY

Ensure that the HI 7638 con­ductivity probe is connected
to the meter securely by align­ing the pins with the socket,
pushing the plug in and
tightening the threaded ring.

• The HI 8936 transmitter may be

wall-mounted at any convenient loca­tion close to the measurement site.
To minimize thermal drifts due to
extreme temperature fluctuations, par­ticularly for outdoors measurements, it
is recommended to protect the trans­mitter inside a casing.

• For the installation of the HI 7635 conductivity probe, use rubber

seals between the probe and the pipe or elbow joints. A pipe
sealant is also recommended to ensure a leak free joint. When
screwing the joints, take care not to overtighten as excessive
pressures can damage the probe.

• The HI 7635 conductivity probe is

supplied with a 3 m (10') cable. The
6-core cable of the probe is connected
to the HI 8936 transmitter as shown.
The connections are color coded for an
easy installation.
See page 24 for the proper connec­tion scheme.

2928

Below Setpoint Control Operation

Short the "SET SELECT" and "COM" connec­tors with a jumper wire. The set contact
relay will close if the measured value is
lower than the setpoint value, and the
"SET ON" LED will light up.

ALARM

Press the "ΔAL" key and the display will show the set tolerance for
the alarm.

Use a small screwdriver to
adjust the "ΔAL" trimmer un­til the desired tolerance is dis­played.

For example, if the set value
is 200 μS/cm and a ΔAlarm
of 50 μS/cm is set, an alarm
will be activated every time
the measured value is higher
than 250 μS/cm or lower
than 150 μS/cm.

When an alarm occurs, the "ALARM" LED
lights up.

COM

SET

SELECT

OPERATING INFORMATION

All parameters are set through the front panel keys and trimmers.
When any key is pressed, the corresponding LED lights up to indicate

that the function is active.
Make sure that the conductivity meter, transmitter and probe are

calibrated before taking measurements (see pages 31, 35 and 39 for
calibration procedures).

SET POINT

To set the working point of the controller, press the SET key. The
display will indicate the current set value.

Use a small screwdriver to
adjust the COARSE and FINE
trimmers until the desired
value is displayed.

Above Setpoint Control Operation

Leave the "SET SELECT" and "COM" connec­tors open. The set contacts relay will close if
the measured value is higher than the
setpoint value, and the "SET ON" LED will
light up.

COM

SET

SELECT

3130

CALIBRATION PROCEDURE OF

HI 8931 & HI 8936 WITH HI 7635

Material needed:

• HI 7635 conductivity probe

• HI 8931 conductivity controller

• HI 8936 conductivity transmitter

• A 20 mA f.s. ammeter (for transmitters without LCD)

• A reference conductivity meter with automatic temperature com­pensation accurately calibrated (e.g. HI 8733).

PROCEDURE

• Connect the HI 7635 probe to the H I8936 transmitter (see page
24 for details).

• Connect the HI 8936 transmitter to the H I8931 controller (see
page 25 for details).

• Connect the HI 8931 controller to the mains (see page 25 for
details).

Before proceeding with the calibration,
make sure that the meter is in measure­ment mode ("MEASURE" LED is on) and
not in set mode.

• Connect the ammeter to the HI 8936 transmitter to monitor the

signal current (see below picture).

MEA

SURE

The alarm contacts of HI 8931 and HI 943500 remain closed during
normal operation. If the measured conductivity level is not within the
tolerance of the set value, the alarm contact will be open.

TAKING MEASUREMENTS WITH HI8931 AND HI 943500

After setting the working point and alarm value, press the "MEASURE" key.
The actual conductivity value of the test solution will be displayed.

TAKING MEASUREMENTS WITH HI8936AL, HI 8936BL,
HI 8936CL, HI8936DL

The conductivity transmitters with LCD
will always display the measurement
value when connected to the HI8931
controllers or a power supply.

3332

• The reading will be converted to mA by the following formula:
mA = K (measured value x 16/2000) + 4
K = conversion factor depending on the model

Model Conversion factor K
HI 8936 A/AL 10

HI 8936 B/BL 100
HI 8936 C/CL 1
HI 8936 D/DL 10

For example, using an HI 8936A, if the measured value is 123.4
mS, then
output current = 10 x (123.4 x 16/2000)+4 = 13.9 mA

Adjust the HI 8936 SLOPE trim­mer to read "13.9 mA" on the
ammeter, or the reading of the
HI 8733 (e.g. 123.4 mS) on
the HI 8936L display. .

• Adjust the HI 8931 SLOPE trimmer until the controller reading is
the same as the one displayed by the HI 8733 (e.g. 123.4 mS).

• Ensure that the HI 7635 conductivity probe is dry.

• When the power is on, the ammeter should read "4.0 mA".

The HI 8936 transmitter with LCD should display "0".

• If not, adjust the transmitter OFF­SET trimmer to read "4 mA" or
"0" on the HI 8936 LCD.

• The HI 8931 controller should dis­play "0" value.

• If not, adjust the HI 8931 OFF-
SET trimmer to display a zero
reading.

• Switch the flow on and allow the
sample solution to flow through
the HI 7635 conductivity probe.
Collect a sample of this solution in
a beaker.

• Measure the conductivity of the
solution with a reference conduc­tivity meter with ATC (HI 8733).
The value obtained will be used
for the transmitter and controller
calibration.

3534

CALIBRATION PROCEDURE OF

HI 8931 & HI 8936 WITH HI 7638

Material needed:

• HI 7638 conductivity probe

• HI 8931 conductivity controller

• HI 8936 conductivity transmitter

• An ammeter (for transmitters without LCD)

• Calibration solutions, according to the different models:

HI 7034 80 mS/cm @25°C

for HI 8931A, HI 8936 A/AL

HI 7030 12.88 mS/cm @25°C

for HI 8931B, HI 8936 B/BL

HI 7031 1413 μS/cm @25°C

for HI 8931C, HI 8936 C/CL

HI 7033 84 μS/cm @25°C

for HI 8931D, HI 8936 D/DL

PROCEDURE

• Connect the HI 7638 to the HI 8936 transmitter (see page 24).

• Connect the HI 8936 transmitter to the HI 8931 controller (see

page 25).

• Connect the HI 8931 controller to the mains (see page 25).

Before proceeding with the calibration,
make sure that the meter is in measure­ment mode ("MEASURE" LED is on) and
not in set mode.

• Connect the ammeter to the HI 8936 transmitter to monitor the

signal current (see below picture).

MEA

SURE

• The calibration is now complete and the instrument is ready for
use. All subsequent measurements will be compensated to 25°C
(77°F).

• If the instrument will not calibrate, refer to the "Probe Mainte­nance and Cleaning" section on page 46.

• If the HI 8936 is not used in conjunction with the HI 8931
controller, connect the transmitter to an external power supply (see
page 20), to the HI 7635 conductivity probe (see page 24) and
to an ammeter (see page 20).

The calibration of the transmitters with LCD (HI 8936L series) does
not require an ammeter.

Follow the above calibration procedure performing the operations
referred to the HI 8936 transmitter only.

3736

• Pour at least 8 cm (3¼") of conductiv­ity solution into a plastic beaker.

• Immerse the probe into the conductivity
solution. The holes on the sleeve must
be completely submerged in the solu­tion.

• Tap the probe repeatedly on the bottom of the beaker and stir it
to ensure that no air bubbles remain trapped inside the sleeve.

• If the temperature of the probe is close to that of the solution, the
display of HI 8931 will stabilize quickly and provide a temperature
compensated conductivity measurement. Allow a few minutes if
there is a temperature difference of about 5°C (9°F) or more for the
ATC circuitry to compensate completely.

• For HI 8936
Adjust the SLOPE trimmer of the HI 8936 transmitter to read on

the ammeter:
"10.4 mA" using HI 7034 and HI 8936 A/AL
"14.304 mA" using HI 7030 and HI 8936 B/BL
"15.304 mA" using HI 7031 and HI 8936 C/CL
"10.72 mA" using HI 7033 and HI 8936 D/DL

8 cm

(3¼")

HI 7030

• Leave the HI 7638 conductivity probe

in air (dry probe).

• When the power is on, the ammeter should read "4.0 mA" or the

HI 8936 transmitter with LCD should display "0".

• If not, adjust the HI 8936 OFF-

SET trimmer to obtain "4 mA" or
"0" on the HI 8936L.

• The HI 8931 controller should dis-

play "0".

• If not, adjust the HI 8931 OFF-

SET trimmer to display a zero
reading.

3938

CALIBRATION PROCEDURE OF

HI 943500 WITH HI 7638

Material needed

• HI 7638 conductivity probe

• HI 943500 conductivity controller

• Calibration solutions, according to the different models:

HI 7034 80mS/cm @25°C for HI 943500A
HI 7030 12.88mS/cm@25°C for HI 943500B
HI 7031 1413 μS/cm @25°C for HI 943500C
HI 7033 84 μS/cm @25°C for HI 943500D

PROCEDURE

• Ensure that the probe is con­nected to the meter securely by
aligning the pins with the
socket, pushing the plug in and
tightening the threaded ring.

• Insert the probe into the sleeve.

• With the conductivity probe in
air, press the "MEASURE" key
to set the meter to measure­ment mode.

• FOR HI8931

When the reading stabilizes, turn the SLOPE trimmer on the front
of the HI 8931 until the LCD reading is the same as the
calibration solution at 25°C (77°F), i.e.

"80.0 mS" using HI 7034 with HI 8931A
"12.88 mS" using HI 7030 with HI 8931B
"1413 μS" using HI 7031 with HI 8931C
"84.0 μS" using HI 7033 with HI 8931D

• The calibration is now complete and the instrument is ready for
use. All subsequent measurements will be compensated to 25°C
(77°F).

• If the instrument will not calibrate, refer to the "Probe Mainte­nance and Cleaning" section on page 46.

• If the HI 8936 is not used in conjunction with the HI 8931
controller, connect the transmitter to an external power supply (see
page 20), to the HI 7638 conductivity probe (see page 24) and
to an ammeter (see page 20).

The calibration of the transmitters with LCD (HI 8936L series) does
not require any ammeter.

Follow the above calibration procedure performing the operations
referred to the HI 8936 transmitter only.

4140

CONDUCTIVITY VERSUS

TEMPERATURE CHART

°C °F HI7030 HI7031 HI 7033 HI7034 HI7035 HI7039

(mS/cm) (mS/cm) (mS/cm) (mS/cm) (mS/cm) (mS/cm)

0 32 7150 776 64 48300 65400 2760

5 41 8220 896 65 53500 74100 3180

10 50 9330 1020 67 59600 83200 3615

15 59 10480 1147 68 65400 92500 4063

16 60.8 10720 1173 70 67200 94400 4155

17 62.6 10950 1199 71 68500 96300 4245

18 64.4 11190 1225 73 69800 98200 4337

19 66.2 11430 1251 74 71300 100200 4429

20 68 11670 1278 76 72400 102100 4523

21 69.8 11910 1305 78 74000 104000 4517

22 71.6 12150 1332 79 75200 105900 4711

23 73.4 12390 1359 81 76500 107900 4805

24 75.2 12640 1386 82 78300 109800 4902

25 77 12880 1413 84 80000 111800 5000

26 78.8 13130 1440 86 81300 113800 5096

27 80.6 13370 1467 87 83000 115700 5190

28 82.4 13620 1494 89 84900 117700 5286

29 84.2 13870 1521 90 86300 119700 5383

30 86 14120 1548 92 88200 121800 5479

31 87.8 14370 1575 94 90000 123900 5575

If you are calibrating HI 8931A or HI 943500A using HI 7030
(12.88 mS/cm @25°C) standard solution, turn the SLOPE trimmer
to display "12.88 mS", with a reference temperature of 25°C (77°F),
while for a reference temperature of 20°C (68°F), the SLOPE trimmer
should be adjusted to display "11.67 mS".

• If the LCD does not show "0", adjust the OFFSET trimmer.

• Pour at least 8 cm (3¼") of conductiv­ity solution into a plastic beaker.

• Immerse the probe into the conductivity
solution, while paying attention that
the holes on the sleeve are completely
submerged.

• Tap the probe repeatedly on the bot­tom of the beaker and stir it to ensure
that no air bubbles remain trapped
inside the sleeve.

• If the temperature of the probe is close to that of the solution, the
display will stabilize quickly and provide a temperature compen­sated conductivity measurement.

Allow a few minutes if there is a temperature difference of about
5°C (9°F) or more for the ATC circuitry to compensate completely.

• When the reading stabilizes, turn the SLOPE trimmer on the

HI943500 front panel until the LCD reads the same value of the

calibration solution at 25°C (77°F), i.e.:

80.0 mS using HI 7034 with HI 943500A

12.88 mS using HI 7030 with HI 943500B
1413 μS using HI 7031 with HI 943500C

84.0 μS using HI 7033 with HI 943500D

• The calibration is now complete and the instrument is ready for
use. All subsequent measurements will be compensated to 25°C
(77°F).

• If the instrument will not calibrate refer to the "Probe Maintenance
and Cleaning" section on page 46.

8 cm

(3¼")

HI 7030

4342

B) Test Slope

Press the "TEST SLOPE" key and the display should indicate the
following values:

HI8931/HI 943500A 100.0 mS ±35.0 mS
HI 8931/HI943500B 10.00 mS ±3.50 mS
HI 8931/HI943500C 1000 μS ±350 μS
HI 8931/HI943500D 100.0 μS ±35.0 μS

Note: The reading obtained by these functions will vary if the OFFSET

and SLOPE trimmers on the front panel are adjusted.

DIAGNOSTIC TESTS

The HI 8931 and HI 943500 controllers are designed with built-in
diagnostic functions to enable the user to check and troubleshoot the
instrument. The checks performed are through the front panel keys and
can be used to isolate the cause of malfunction.

Press the "MEASURE" key before pro­ceeding the following tests.

A) Test Offset

Press the "TEST OFFSET" key and the display should indicate the
following values:

HI8931/HI 943500A 0.0 mS ±1.0 mS
HI8931/HI 943500B 0.00 mS ±0.10 mS
HI8931/HI 943500C 000 μS ±100 μS
HI 8931/HI943500D 0.0 μS ±1.0 μS

4544

Example #3

Example #4

Example #5

INSTALLATION EXAMPLES

Some typical installation setups are shown in the following examples:

Example #1

Example #2

4746

ACCESSORIES

CONDUCTIVITY CALIBRATION SOLUTIONS

HI 7030L 12880 μS/cm calibration solution, 500 mL
HI 7030M 12880 μS/cm calibration solution, 230 mL
HI 7031L 1413 μS/cm calibration solution, 500 mL
HI 7031M 1413 μS/cm calibration solution, 230 mL
HI 7033L 84 μS/cm calibration solution, 500 mL
HI 7033M 84 μS/cm calibration solution, 230 mL
HI 7034L 80000 μS/cm calibration solution, 500 mL
HI 7034M 80000 μS/cm calibration solution, 230 mL
HI 7035L 111800 μS/cm calibration solution, 500mL
HI 7035M 111800 μS/cm calibration solution, 230 mL
HI 7039L 5000 μS/cm calibration solution, 500 mL
HI 7039M 5000 μS/cm calibration solution, 230 mL

OTHER ACCESSORIES

HI 731326 Calibration screwdrivers (20 pcs)
HI 779/P 6-wire cable (100 m/330' roll)
HI 8733 Portable conductivity meter with automatic tem-

perature compensation

PROBE MAINTENANCE & CLEANING

The probe can be compensated for normal contamination by a process of
re-calibration.
It is recommended to remove the probe from its installation regularly for
maintenance.

For HI7635 only:
Deposits on the conductivity probe can be removed by immersing the probe
in 0.1 N hydrochloric acid for about 30 minutes. Heavier deposits may
demand longer immersion periods.
Rinse the probe thoroughly with water prior to the reinstallation.
On reinstalling, check the seals carefully to ensure that a leak-free
connection is obtained.

For HI7638 only:
Rinse the probe with tap water. If a more thorough cleaning is desired,
unscrew the plastic sleeve and clean the sensors with a nonabrasive cloth
or alcohol.
After cleaning the probe, re-calibrate the instrument. If the instrument
will not calibrate with a clean probe, you must replace the probe.

Note: Always re-calibrate the meter when attaching a new probe.

All HANNA instruments® meters are warranted for two years against
defects in workmanship and materials when used for their intended
purpose and maintained according to instructions.

The probes are warranted for a period of six months.

This warranty is limited to repair or replacement free of charge.

Damages due to accident, misuse, tampering or lack of prescribed
maintenance are not covered.

If service is required, contact the dealer from whom you purchased the
instrument. If under warranty, report the model number, date of
purchase, serial number and the nature of the failure. If the repair is not
covered by the warranty, you will be notified of the charges incurred.

If the instrument is to be returned to HANNA instruments®, first obtain
a Returned Goods Authorization Number from the Customer Service
department and then send it with shipment costs prepaid.

When shipping any instrument, make sure it is properly packaged for
complete protection.

All rights are reserved. Reproduction in whole or in part is prohibited
without the written consent of the copyright owner.

WARRANTY

CONDUCTIVITY PROBES

HI 7635 In-line conductivity probe with 3 m (10') cable

(for HI 8936 only)

HI 7638 Conductivity probe for tank installation, with 3 m

(10') cable (for HI 8936 or HI 943500)

73mm

2.87"

52mm

2.04"

1" NP

T

142mm

5.60"

Hanna Instruments reserves the right to modify the design,

construction and appearance of its products without

advance notice.

CE DECLARATION OF CONFORMITY

Recommendations for Users

Before using these products, make sure that they are entirely suitable for the
environment in which they are used.
Operation of these instruments in residential area could cause unacceptable interfer­ences to radio and TV equipments, requiring the operator to take all necessary steps
to correct interferences.
The trimmers are sensitive to electrostatic discharges. It is recommended to use anti­static screwdrivers.
Unplug the instrument from the power supply before replacing the fuse. External cables
to be connected to the rear panel should end with cable lugs.
To maintain the EMC performance of this equipment, use the recommended cables
mentioned on this instruction manual.
Any variation introduced by the user to the supplied equipment may degrade the
instruments' EMC performance.
To avoid electrical shock, do not use these instruments when voltages at the
measurement surface exceed 24 Vac or 60 Vdc.
To avoid damages or burns, do not perform any measurement in microwave ovens.

MANCDPRCR5 09/05

Australia:

Tel. [phone] • Fax [phone]

China:

Tel. [phone] • Fax [phone]

Egypt:

Tel. & Fax [phone]

Germany:

Tel. [phone] • Fax [phone]

Greece:

Tel. [phone] • Fax [phone]

Indonesia:

Tel. [phone] • Fax [phone]

Japan:

Tel. [phone] • Fax [phone]

Korea:

Tel. [phone] • Fax [phone]

Malaysia:

Tel. [phone] • Fax [phone]

Singapore:

Tel. [phone] • Fax [phone]

South Africa:

Tel. [phone] • Fax [phone]

Taiwan:

Tel. [phone] • Fax [phone]

Thailand:

Tel. [phone] • Fax [phone]

United Kingdom:

Tel. [phone] • Fax [phone]

USA:

Tel. [phone] • Fax [phone]

For e-mail contacts and complete list of Sales and
Technical offices, please see www.hannainst.com

SALES & TECHNICAL SERVICE CONTACTS