Hanna Instruments HI 720 User manual

Instruction Manual
HI 720
Conductivity
Process Controller
with Inductive Probe

3
TABLE OF CONTENTS
WARRANTY ......................................................................................................4
PRELIMINARY EXAMINATION.............................................................................5
MODEL IDENTIFICATION..................................................................................5
GENERAL DESCRIPTION & THEORY OF OPERATION .........................................6
SPECIFICATIONS .............................................................................................9
FUNCTIONAL DESCRIPTION...........................................................................10
INSTALLATION................................................................................................12
OPERATIONAL GUIDE ....................................................................................14
• SETUP MODE ...........................................................................................14
• CALIBRATION MODE................................................................................34
• CONTROL MODE ....................................................................................37
• IDLE MODE..............................................................................................43
• LAST CALIBRATION DATA VIEWING MODE ................................................43
• DIAGNOSTIC MODE................................................................................44
TEMPERATURE COMPENSATION.....................................................................46
CONCENTRATION CURVES............................................................................48
HOLD MODE .................................................................................................50
IN-LINE CLEANING.........................................................................................52
COMMUNICATION........................................................................................54
• PC COMMUNICATION.............................................................................54
• SHORT MESSAGING SERVICE (SMS)..........................................................67
• MODEM CONNECTION ..........................................................................71
ERRORS - FAULT CONDITIONS .......................................................................73
ALARM - ERROR CONFIGURATION.................................................................74
SELFTEST PROCEDURES..................................................................................77
ACCESSORIES ................................................................................................80

4
WARRANTY
All Hanna Instruments meters are guaranteed for two years (sensors,
electrodes and probes for six months) against defects in workmanship and
materials when used for their intended purpose and maintained according to
instructions.
This warranty is limited to repair or replacement free of charge. Damage 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 shipping costs prepaid.
When shipping any instrument, make sure it is properly packaged for complete
protection.
Dear Customer,
Thank you for choosing a Hanna Instruments product. Please read this instruction
manual carefully before using the controller. For more information about
Hanna Instruments and our products, visit www.hannainst.com or e-mail us at
[email protected].
For technical support, contact your local Hanna Instruments Office or e-mail us
at [email protected].
Hanna Instruments reserves the right to modify the design,
construction or appearance of its products without advance notice.
All rights are reserved. Reproduction in whole or in part is prohibited without the
written consent of the copyright owner, Hanna Instruments Inc., Woonsocket,
Rhode Island, 02895, USA.

5
PRELIMINARY EXAMINATION
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 notice-
able damage, notify your Dealer or the nearest Hanna Customer Service Center
immediately.
Note Save all packing materials until you are sure that the instrument func-
tions correctly. Any damaged or defective items must be returned in
their original packing materials together with the supplied accessories.
MODEL IDENTIFICATION
The models HI 720 XYZ-αare conductivity controllers.
The meaning of the last letters is according to the following scheme:

6
GENERAL DESCRIPTION & THEORY OF OPERATION
This instrument allows conductivity measurements without any electrical contact
between electrodes and process fluid.
The measurement is based on inductive coupling of two toroidal transformers
by the liquid.
The instrument supplies a high frequency, reference voltage to the “Drive Coil”,
and a strong magnetic field is generated in the toroid.
The liquid passes through the hole in the toroid and can be considered as one-turn
secondary winding. The magnetic field induces a voltage in this liquid winding, the
current induced in the flow is proportional to this voltage, and the conductance
of the liquid one-turn winding is according to the Ohm’s law.
The conductance is proportional to the specific conductivity and a constant factor
determined by the sensor geometry and installation.
The liquid also passes through the second toroid and therefore the liquid turn
can be considered as a primary winding of the second toroidal transformer. The
current in the liquid will create a magnetic field in the second toroid, and the
induced current can be measured as an output.
The output current of this “Receive Coil” is therefore proportional to the specific
conductivity of process liquid.

7
For an inductive cell, the cell constant is defined as the measured conductivity,
obtained by making a loop through the sensor with a resistor R, multiplied by
that R value.
The cell constant depends only on the sensor geometry. However, when the probe
is immersed in a liquid, the induced current in the solution is affected by the piping
or any other container where the probe is inserted. This effect is negligible when
there is an area of at list 3 cm of liquid around the cell.
Otherwise, it is necessary to multiply measurements by the installation factor:
Conductivity = (cell constant)(installation factor)/(measured resistance)
The installation factor is < 1 for conductive piping/containers, and > 1 for
non-conductive piping/containers.
Since this type of sensor has no electrodes, common problems due to the electrode
contact, such as polarization and contamination, will not affect the performance
of our electrodeless sensor.
The probe working life is extremely long and the sensor maintenance will be an
exceptional operation.
The controllers are equipped with a graphic display, easy to understand as your
cellular phone. Simple messages guide the users through all operations and
parameter setting.

8
The main features of the HI 720 controller series include:
• Measurement and control of conductivity or concentration
• Concentration can be measured as usual TDS (fixed ratio) or through custom
conductivity/temperature/concentration curves
• Customizing temperature coefficient table and NaCl temperature compensation
according to IEC 746-3, in addition to the standard linear compensation
• Auto-ranging
• Display reading offset adjustment for temperature
• Temperature level alarm
• Cleaning in place activated through two cleaning commands, or triggered by
a variety of events
• Hold management, including a digital input to enter the hold mode through
an external trigger
• Digital transmitter input
• Pt100 or Pt1000 temperature sensor with automatic recognition and damage test
• Calibration time-out
• Logging of the last 100 error, configuration and cleaning events
• Alarm fault current (3.6 mA or 22 mA)
• SMS messages sending
• Alarm configuration can be customized: different errors can lead different
actions (alarm relay activation, fault current, hold mode, automatic cleaning,
SMS message)
• RS485 communication with additional capabilities, such as error log file down-
loading and cleaning commands
• Daily programmable control timing
• Diagnostic features
• Password protection

9
SPECIFICATIONS
Range 0 to 2000 mS/cm (auto-ranging)
-30 to 130°C / -22 to 266°F
Resolution 1 µS/cm (0 to 1999 µS/cm)
0.01 mS/cm (2.00 to 19.99 mS/cm)
0.1 mS/cm (20.0 to 199.9 mS/cm)
1 mS/cm (200 to 2000 mS/cm)
0.1°C / 0.2°F
Accuracy ±2% f.s. (conductivity) / ±0.5°C / ±1°F
Temp. Compensation Automatic or manual, -30 to 130°C
Temperature Probe 3-wire or 2-wire Pt100 or Pt1000 sensor
with automatic recognition and damage test
Digital Input Digital Transmitter, Hold & Advanced Cleaning inputs
Digital Output 1 digital insulated contact closed upon Hold mode
Analog Output 1 or 2 independent outputs;
0-22 mA (configuring as 0-20 mA or 4-20 mA)
Digital Serial Output RS485
Dosing Relay 1, 2, 3 or 4 electromechanical relays SPDT;
5A-250 Vac, 5A-30 Vdc (resistive load);
fuse protected: 5A, 250 V fuse
Alarm Relay 1 electromechanical relay SPDT;
5A-250 Vac, 5A-30 Vdc (resistive load);
fuse protected: 5A, 250 V fuse
Installation Category II
Power Supply 24 Vdc/ac, or
115 Vac or 230 Vac or 100 Vac ±10%, 50/60 Hz;
fuse protected: 400 mA, 250 V fast fuse
Power Consumption 10 VA
Max Oscillation Frequency 8 MHz
Environment 0 to 50°C (32 to 122°F); RH max 85% non-condensing
Enclosure Single case 1/2 DIN
Weight Approx. 1.6 kg (3.5 lb.)

10
FUNCTIONAL DESCRIPTION
1. Graphic display (128 x 64 dots)
2. DIAG key, to enter/exit diagnostic mode; to change the conductivity or
concentration range while in setup or calibration mode
3. SETUP key, to enter/exit setup mode
4. CAL DATA key, to enter/exit last calibration data viewing mode
5. CAL key, to enter/exit calibration mode
6. key, to increase current digit by 1, shift to next option, or move to next
record while in diagnostic mode
7. key, to decrease current digit by 1, shift to previous option, or move to
previous record while in diagnostic mode
8. key, to cyclically change temperature compensation option for conductivity
readings: compensation enabled (temperature is continuously displayed) or
compensation disabled (actual reading). Only displayed values are affected
by this key; control and logging are not affected.
9. CFM key, to confirm current choice
10. Contact LEDs, each turns on when the corresponding relay is energized
11. Status (red) and alarm (green) LEDs

11
1. Connections for conductivity probe
2. Connections for Pt100/Pt1000 temperature sensor
3. Digital Transmitter input
4. Hold input
5. Advanced Cleaning input (optional)
6. RS485 output terminal
7. Hold output
8. Analog output #1
9. Analog output #2 (optional)
10. Power supply input
11. Relay #3 - for Advanced Cleaning feature (optional)
12. Relay #4 - for Advanced Cleaning feature (optional)
13. Relay #1 - first dosing terminal
14. Relay #2 - second dosing terminal (optional)
15. Alarm relay

12
INSTALLATION
Mechanical Dimensions
Electrical Connections
•Power Input: connect a 3-wire power cable to the line (L), earth
(PE) and neutral (N) terminal connections.
Power: 100 Vac-120 mA / 115 Vac-100 mA / 230 Vac-50 mA.
Line Contact: 400 mA fuse inside.
PE must be connected to ground; leakage current 1 mA.
• Probe Connections (#1 at page 9): connect the Tx and Rx coaxial
cables to the relevant terminals, as indicated. Connect the probe cable shield
to the “Shield” terminal.
• Pt100/Pt1000 Terminals (#2 at page 9): these contacts connect the Pt100/
Pt1000 sensor for automatic temperature compensation.
If the conductivity probe features a built-in Pt100/Pt1000 sensor, connect the
related wires to pins 1, 2 and 3; pin 4 will not be used.

13
It is also possible to use a separate Pt100/Pt1000 temperature probe. In the
case of shielded wire, connect the shield to pin 4. In the case of a 2-wire sen-
sor connect the Pt100/Pt1000 to pins 1 and 3, and short pins 2 and 3 with
a jumper wire.
If the Pt100/Pt1000 probe has more than 2 wires, connect the two wires of
one end to pins 2 and 3 (pin 2 is an auxiliary input to compensate for the
cable resistance) and one wire from the other end to pin 1. Leave the fourth
wire unconnected, if present.
Note The instrument automatically recognizes the sensor type (Pt100 or
Pt1000).
• Analog Outputs: when using shielded cable, if the shield is not connected at
the other end of the cable, then connect it to the “+” terminal, otherwise leave
it floating.
Note All cables connected to rear panel should end with cable lugs.
Note A circuit breaker (rated 10 A max.) must be connected in close proxim-
ity to the equipment, and in a position easy to reach by the operator,
for disconnection of the instrument and all devices connected to the
relays.

14
OPERATIONAL GUIDE
The HI 720 process controller can operate in six main modes:
• Setup mode
• Calibration mode
• Control mode
• Idle mode
• Last calibration data viewing mode
• Diagnostic mode (active errors & event log file scrolling)
All operating modes are described in the following sections.
Setup Mode
The Setup mode allows the user to set all needed characteristics of the meter. To
enter the mode, press the SETUP key and enter the password when the device is
in idle or control mode.
If the correct password is not entered, the user can view the setup parameters
(except passwords, phone numbers and PIN code), but not modify them (and the
device remains in control mode).
Entering the Password
• Press the SETUP key to enter the setup mode.
The display will show “0000” (default value),
with the first digit highlighted.
• Enter the first digit of the password by using the
up & down arrow keys.
• Move to the next digit with the key and enter the desired value as described
above. Continue for the last two digits. When the whole password has been
inserted, press CFM to confirm.
Entering Setup Items
• After the password has been confirmed, the dis-
play will show the name of the first setup group
(General Setting).
• Using the arrow keys it is possible to cycle through
all setup groups, while pressing SETUP will exit
the mode, and pressing CFM will confirm the
desired selection.
• Once a group is selected, the display shows the
first parameter of the group together with its
current value.

15
The user can choose the desired parameter with the up & down arrow keys,
and confirm the selection by pressing CFM.
Note For some groups, it is necessary to enter several sublevels before
choosing a parameter value. Follow the displayed messages to pro-
ceed, confirm or exit each screen.
• If a fixed set of values is available for the select-
ed item, use the arrow keys to switch between
them. Otherwise, if a numeric value has to be
entered, use the arrow keys to change the value
of the highlighted digit and cycle through the
number’s digits.
• Once a value is set, press the CFM key to con-
firm, and the instrument will turn to the previous
screen.
Note After modifying a value in the concentration curve triplets or in
the conductivity/temperature couples for the temperature com-
pensation algorithm, then it is not possible to exit without saving. To
return to the previous value, the number must be entered again.
• If a wrong value is confirmed, the “Invalid value!”
or “Invalid choice!” message advises the user,
the value is not accepted and the instrument will
not switch to the next item until a correct value
will be confirmed.
• When the last item of the group is reached, by pressing the CFM key again the
display will show the group name. The group can then be changed by pressing
the up & down arrow keys.
Note If no activity is performed for about 5 minutes after entering the setup
mode, the mode is automatically exited and the instrument returns
to the previous mode.

16
Setup Item Description Valid Values Default
GENERAL SETTINGS
G.00 Measurement mode Conductivity, Conductivity
(see note 8) Concentration, TDS
G.01 Conductivity range Auto range, Auto range
1999 µS/cm,
19.99 mS/cm,
199.9 mS/cm,
2000 mS/cm
G.02 TDS range Auto range, Auto range
1000 ppm, 10.00 ppt,
100.0 ppt, 1000 ppt
G.03 Concentration unit Auto (ppm/ppt), Auto
(see note 31) ppm, ppt, % (ppm/ppt)
G.04 Concentration XXXX, XXX.x, XX.xx
format XX.xx, X.xxx
G.05 TDS factor 0.00 to 1.00 0.50
G.06 Moving average 1 to 30 1
length (see note 30)
G.10 Factory ID 0000 to 9999 0000
G.11 Process ID alias 00 to 99 00
RS485 address
G.13 Language English, Italiano English
G.14 LCD contrast 0 to 10 6
G.15 LCD backlight On, Off On
G.98 Calibration 0000 to 9999 0000
password (see note 2)
G.99 General password 0000 to 9999 0000
(see note 2)
TEMPERATURE
b.01 Compensation mode Automatic (ATC), ATC
(see notes 7, 20) Manual (MTC)
b.02 Start manual temp. -30.0 to 130.0°C 25.0°C
(see notes 7, 20)
This table lists all available setup items together with their code, short description,
valid values and default setting.

17
Setup Item Description Valid Values Default
TEMPERATURE
b.03 Temperature measure °C, °F °C
unit (see note 32)
b.10 Temp. compensation Linear, Linear
algorithm (note 28) NaCl (IEC 746, table BII),
User: user defined table
b.11 Reference temp. 20°C, 25°C 25°C
(see note 28)
b.12 Temp. coefficient 0.00 to 20.00 % 2.00 %
(see notes 28, 29)
Temperature Compensation Table
b.31 Number of couples 2 to 10 2
b.32 Edit/view couple 1 to b.31 item value 1
b.33 User table: actual 0 to f.s. see note 33
conductivity value for
the couple selected in b.32
b.34 User table: -30.0 to 130.0°C see note 33
temperature value for
the couple selected in b.32
Temperature Level Alarm (see Note 36)
b.41 Max temperature -30.0 to 130.0°C 130.0°C
b.42 Min temperature -30.0 to 130.0°C -30.0°C
Reading Offset
b.50 Actual reading measurement -10.0°C measurement
(for ATC only, to measurement +10°C (see note 15)
see notes 15, 20)
b.51 Temperature offset -10.0°C to +10.0°C 0.0°C
(ATC only, notes 15, 20)
CONCENTRATION
d.00 Concentration curve 1 to 4 1
in use
Curve 1/2/3/4 Table (see note 34)
d.01 Number of triplets 1 to 25 1
d.02 Edit/view triplet 1 to d.01 value 1

18
Setup Item Description Valid Values Default
Curve 1/2/3/4 Table (see note 34)
d.03 Not compensated 0 to f.s. 0 µS/cm
conductivity value for
the triplet selected in d.02
d.04 Temperature value for -30.0 to 130.0°C 0.0°C
the d.02 triplet
d..05 Concentration value 0 to f.s 0 ppm
for the d.02 triplet
CONTROL
C.00 Control enable On, Off Off
Setpoint 1
C.10 Setpoint 1 mode Disabled, On/Off low
(M1) On/Off high,
(see note 1) On/Off low,
PID high (if available),
PID low (if available)
C.11 Setpoint 1 value 0 to f.s. 500 µS/cm
(S1) (see note 1)
C.12 Setpoint 1 0 to f.s. 20 µS/cm
hysteresis (H1) (see note 1)
C.13 Setpoint 1 Up to f.s and ≠0 20 µS/cm
deviation (D1) (see note 1)
C.14 Setpoint 1 reset time 0.1 to 999.9 minutes 999.9 min.
C.15 Setpoint 1 rate time 0.0 to 999.9 minutes 0.0 min.
Setpoint 2
C.20 Setpoint 2 mode Disabled, On/Off low
(M2) On/Off high,
(see note 1) On/off low,
PID high (if available),
PID low (if available)
C.21 Setpoint 2 value 0 to f.s. 1500 µS/cm
(S2) (see note 1)
C.22 Setpoint 2 0 to f.s. 20 µS/cm
hysteresis (H2) (see note 1)
C.23 Setpoint 2 Up to f.s and ≠0 20 µS/cm
deviation (D2) (see note 1)

19
Setup Item Description Valid Values Default
Setpoint 2
C.24 Setpoint 2 reset time 0.1 to 999.9 minutes 999.9 min.
C.25 Setpoint 2 rate time 0.0 to 999.9 minutes 0.0 min.
Alarms
C.30 Low alarm value 0 to f.s 100 µS/cm
(LA) (see note 18) (see note 1)
C.31 High alarm value 0 to f.s 1900 µS/cm
(HA) (see note 18) (see note 1)
C.32 Max relay ON time 1 to 60 minutes 60 min.
(then an alarm is generated)
C.33 Alarm mask time 00:00 to 30:00 min. 00:30
(see notes 18, 27)
C.34 Alarm hysteresis 0 to f.s. 20 µS/cm
(AH) (see note 18)
Programmable Control
C.41 Hold time start (note 6) 00:00 to 23:59 00:00
C.42 Hold time stop (note 6) 00:00 to 23:59 00:00
C.51 Monday hold mode Off: disabled, Off
On: enabled
C.52 Tuesday hold mode Off: disabled, Off
On: enabled
C.53 Wednesday hold Off: disabled, Off
mode On: enabled
C.54 Thursday hold Off: disabled, Off
mode On: enabled
C.55 Friday hold mode Off: disabled, Off
On: enabled
C.56 Saturday hold mode Off: disabled, Off
On: enabled
C.57 Sunday hold mode Off: disabled, Off
On: enabled
Other Parameters
C.60 Proportional control 01:00 to 30:00 min. 05:00 min.
period (if available)

20
Setup Item Description Valid Values Default
Other Parameters
C.70 Hold mode end delay 00 to 99 seconds 00 sec
C.80 On/Off control 00:00 to 30:00 min. 00:00 min
action delay (note 26)
OUTPUT
Relays
O.01 Relay 1 mode Disabled, Control-
(see notes 16, 17) Control-setpoint 1, setpoint 1
Control-setpoint 2,
Simple cleaning,
Hold mode
O.02 Relay 2 mode Disabled, Control-
(see notes 16, 17) Control-setpoint 1, setpoint 2
Control-setpoint 2,
Simple cleaning,
Hold mode
O.03 Relay 3 mode Disabled, Disabled
(see notes 12, 16) Simple cleaning,
Advanced cleaning,
Hold mode
O.04 Relay 4 mode Disabled, Disabled
(see notes 12, 16) Simple cleaning,
Advanced cleaning,
Hold mode
O.05 Hold digital output Disabled or Hold mode
Hold mode
Analog Output 1
O.10 Analog output 1 Recorder or Recorder
mode (notes 1, 17) Control-setpoint 1
O.11 Analog output 1 0-20 mA or 4-20 mA
type 4-20 mA
O.12 Analog output 1 0 to f.s. 0 µS/cm
 minimumvalue (O_VARMIN1≤
(O_VARMIN1) O_VARMAX1 -5% f.s. for
O_VARMAX1, O_VARMIN1
  ≤O_HOLD1≤O_VARMAX1)