Hanna Instruments HI 8614 User manual

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pH and ORP
Transmitters
HI 8614 • HI 8614L
HI 8615 • HI 8615L
Instruction Manual
www.hannainst.com

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PRELIMINARY EXAMINATION ....................................................................... 3
GENERAL DESCRIPTION ............................................................................. 3
SPECIFICATIONS OF HI 8614 & HI 8614L .................................................. 5
SPECIFICATIONS OF HI 8615 & HI 8615L .................................................. 6
TERMINAL BOARD CONNECTIONS ................................................................ 7
pH CALIBRATION WITH AUTOMATIC TEMPERATURE COMPENSATION
(HI 8614 FAMILY) ................................................................................... 9
pH CALIBRATION WITH FIXED TEMPERATURE COMPENSATION
(HI 8614 FAMILY) ................................................................................. 12
ORP CALIBRATION (HI8615 FAMILY) ........................................................ 13
ELECTRODE CONDITIONING & MAINTENANCE ............................................... 17
TEMPERATURE CORRELATION FOR pH SENSITIVE GLASS ............................... 20
INSTALLATION PROCEDURE AND EXAMPLES ................................................. 22
ACCESSORIES ........................................................................................ 25
TABLE OF CONTENTS
HI 8614, HI 8614L, HI 8615 and HI 8615L are guaranteed for two
years against defects in workmanship and materials when used for
their intended purpose and maintained according to instructions.
Electrodes and probes are guaranteed for six months. This warranty is
limited to repair or replacement free of charge.
Damage due to accidents, misuse, tampering or lack of prescribed
maintenance is 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 problem. 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 Technical
Service department and then send it with shipping costs prepaid.
When shipping any instrument, make sure it is properly packed for
complete protection.
WARRANTY
Dear Customer,
Thank you for choosing a Hanna Instruments product.
Please read this instruction manual carefully before using these
instruments.
This manual will provide you with the necessary information for correct
use of these instruments, as well as a precise idea of their versatility.
If you need additional technical information, do not hesitate to e-mail
us at [email protected] or view our worldwide contact list at
www.hannainst.com.

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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 noticeable damage, notify your Dealer.
Note:Save all packing material until you are sure that the instrument
functions correctly. All defective items must be returned in the
original packing material together with the supplied accessories.
GENERAL DESCRIPTION
HI 8614 /HI 8614L (pH) and HI 8615 /HI 8615L (ORP) are 2-wire
water-resistant transmitters specially designed for long distance
measurement of pH or ORP in industrial applications.
HI 8614 and HI 8615 are models without LCD, and the HI 8614L
and HI 8615L are models with LCD.
The LCD allows easy verification and monitoring of measured values,
and provides easier calibration and maintainance.
The pH or ORP signal is transmitted in a 2-wire current loop in the range
of 4 to 20 mA.
HI 8614 and HI 8614L, can be connected to the Hanna process
instruments HI 8510,HI 8710, HI 8711 or to any recorder,
computer or data monitor that accepts 4 to 20 mA input.
HI 8615 and HI 8615L, can be connected to the Hanna process
instruments HI 8512, HI 8720 or to any recorder, computer or data
monitor that accepts 4 to 20 mA input.

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The transmitters use a universal BNC socket for quick and secure
connection to any electrode with a BNC connector.
For HI 8614 family models the temperature compensation is
performed by the transmitter's ATC circuitry if the temperature probe
(HI 76608, optional) is attached. If ATC is not required, it is possible
to substitute the temperature probe with a fixed resistor.
The input is isolated from the current loop to eliminate problems
related to ground loop, low insulation cables, multiple electrode
connections, and a common mode voltage of up to 100 V ensures true
differential readings.
The terminal board of the transmitter provides for connection of power
supply, pH or ORP electrodes and temperature probe (for HI 8614
family models only).
The unit is enclosed in a protective casing conforming to IP 65
standards.
Ordering codes:
Code Range LCD
HI 8614 0.00 to 14.00 pH NO
HI 8614L 0.00 to 14.00 pH YES
HI 8615 ±1000 mV NO
HI 8615L ±1000 mV YES

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SPECIFICATIONS OF HI 8614 & HI 8614L
Range 4 to 20 mA / 0.00 to 14.00 pH
Resolution 0.01 mA / 0.01 pH
Accuracy
(@25 °C/77 °F) ±0.02 mA / ±0.02 pH
Calibration Offset: ±2.2 mA / ±2 pH
Slope: ±0.5 mA / 86 to 116%
Temperature Compensation
Fixed or automatic from 0 to 100 °C
(32 to 212 °F) with HI 76608 probe
InputImpedance 1012 Ohm
Output 4-20mA (isolated)
Installation Category I I
Protection IP 65
Environment 0 to 50 °C (32 to 122 °F);
RH max 95% non-condensing
Power Supply HI 8614: 18 to 30 Vdc
HI 8614L: 20 to 36 Vdc
Load Max 500 Ohm
Dimensions 165 x 110 x 71 mm
(6.5 x 4.3 x 2.8'')
Weight 1 kg (2.2 lb.)

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SPECIFICATIONS OF HI 8615 & HI 8615L
Range 4 to 20 mA / ±1000 mV
Resolution 0.01 mA / 1 mV
Accuracy
(@25 °C/77 °F) ±0.02 mA / ±5 mV
Calibration Offset: ±0.8 mA / ±100 mV
Slope: ±0.8 mA / 90 to 110%
Input Impedance 1012 Ohm
Output 4-20 mA (isolated)
Installation Category I I
Protection IP 65
Environment 0 to 50 °C (32 to 122 °F);
RH max 95% non-condensing
Power Supply HI 8615: 18 to 30 Vdc
HI 8615L: 20 to 36 Vdc
Load Max 500 Ohm
Dimensions 165 x 110 x 71 mm
(6.5 x 4.3 x 2.8'')
Weight 1 kg (2.2 lb.)

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TERMINAL BOARD CONNECTIONS
Unscrew the 4 screws and remove the top cover.
Therearethreecableglandsonthetransmittercover.Thelargecablegland
with the split in the rubber is for the electrode.
Connect the positive supply to the strip terminal “+VE LOOP“ and the
negative supply to the terminal “-VE LOOP“ of the transmitter terminal
block.
Black and Red contacts (HI 8614L and HI 8615L only).
- Red - LCD board V+(factory connected to the LCD)
- Black - LCD board V-(factory connected to the LCD)

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The wire between the transmitter and the recorder/indicator/controller
should be a PVC insulated two wire with a wire diameter of at least
0.7 mm. This wire is fed through one of the smaller cable glands. The
maximum distance between the power supply and the amplifier is
300 m (1000'). It is not necessary to use shielded cable. The
transmitter is protected against inversion of supply voltage.
Electrodeconnection:connecttheBNC
of the cable to the BNC socket on the
transmitter.
ForHI8614familyonly:forautomatic
temperature compensation, connect
the2terminalsofthetemperatureprobe
(HI76608, optional)to“TEMP. PROBE“
terminals.
If automatic temperature compensation
is not required, short the “TEMP.
PROBE“terminals with a resistance
according to the external temperature:
Temperature (°C) Resistance (Ohms)
01634
10 1774
20 1922
30 2078
40 2242
50 2412
60 2590
A2kohmresistor isfactorymountedfor25°Ctemperature compensation.

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pH CALIBRATION WITH AUTOMATIC
TEMPERATURE COMPENSATION (HI 8614 family)
INITIAL PREPARATION
•Connect the pH electrode to the
BNC socket.
•Connect the temperature probe to
the transmitter.
Pour small quantities of pH7.01 and
pH4.01 solution into two clean bea-
kers.
For accurate calibration use two beakers for each buffer solution, the
first one for rinsing the electrode, the second one for calibration. In
this way contamination of the buffers is minimized.
To get accurate readings, use pH7.01 and pH4.01 if you are going
to measure acid samples or pH 7.01 and pH 10.01 for alkaline
measurements.
Note:With HI 8614L the instruments display can be used during
calibration without the need to connect the ammeter and the
reading is directly expressed in pH units.

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PROCEDURE
•Disconnect the +ve supply cable from “+VE LOOP“ terminal
and connect a 20 mA f.s. ammeter between the +ve cable and
“+VE LOOP“ terminal.
•Remove the protective cap from the electrode,
rinse it with some pH 7.01 solution or immerse it
in the pH 7 rinse solution, then immerse the pH
electrode and temperature probe into pH7.01
calibration buffer solution; shake briefly and wait
for the reading to stabilize.
Note:The tip of the electrode should be
submerged approximately 4 cm (1½")
into the solution. The temperature probe
should be located as close to the pH
electrode as possible.
•Adjust the offset trimmer until the ammeter reads 12 mA or the
display shows “7.01“ if the temperature of the buffer is at 25 °C.
For other buffer temperatures, refer
to page 12 for the appropriate
mA / pH reading.
•Rinse the electrode with tap water or distilled
water and a small amount of pH 4.01 or 10.01
buffer solution or immerse it in the pH 4 rinse
solution (2nd calibration point). Dip the electrode
and the temperature probe into pH 4.01 (or
10.01) calibration buffer solution, shake briefly
and wait for a few minutes for reading to
stabilize.

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•Adjust the slope trimmer until the ammeter reads 8.58 mA for
HI 8614 and HI 8614L or the display shows “4.01“ at 25 °C.
For other buffer temperatures, refer to page 12 for the appropriate
mA / pH reading.
If you are using pH 10.01 buffer
solution adjust the slope trimmer
until the ammeter read 15.43 mA at
25 °C (77 °F) or the value indicated at
page 12.
FOR HI8614L ONLY
The Display Module is factory calibrated, so that the LCD display
results are referred to the 4-20 mA loop current (e.g. LCD displays
0.00 pH when the loop current is 4.00 mA and displays 14.00 pH
when the current is 20.00 mA).
Under normal application, adjustment on this module may not be
necessary.
If routine check is required, the following procedures shall be performed.
•Follow the procedure at page 10 to perform calibration on the
transmitter module (using a ammeter).
•Simulate a 4.00 mA loop current for the transmitter (i.e. 0.00 pH
as Electrode input) and check for display reading.
•Simulate a 20.00 mA loop current for the transmitter (i.e.
14.00 pH as Electrode input) and check for display reading.
Note:When HI 8614 or HI 8614L instruments are used in
conjunction with the new Hanna indicator HI 8510 or
controllers HI 8710 and HI 8711, the calibration can also
be performed on the indicator/controller. In this case slight
calibration adjustment can be made on the indicator/
controller even if the whole system calibration is advised,
always starting from the transmitter.

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HI 8614, HI 8614L
pH CALIBRATION WITH FIXED TEMPERATURE
COMPENSATION (HI 8614 family)
•Take the temperature of the buffer
solutions using a Checktemp or a
thermometer with a resolution of at
least 1 °C.
•Connect the appropriate resistor
to the “TEMP. PROBE”terminals
(see page 8) depending on the
temperature of the calibration solution.
•Follow the procedure as outlined in the calibration with automatic
temperature compensation and use the thermometer reading to
adjust the trimmer until the ammeter reads the value according
to the following table.
erutarepmeT reffuB10.4Hp reffuB10.7Hp reffuB10.01Hp
Cº Fº Hp Am Hp Am Hp Am
0 23 10.4 43.9 31.7 21.21 23.01 59.41
5 14 00.4 33.9 01.7 90.21 42.01 88.41
01 05 00.4 33.9 70.7 60.21 81.01 38.41
51 95 00.4 33.9 40.7 40.21 21.01 77.41
02 86 00.4 33.9 30.7 30.21 60.01 27.41
52 77 10.4 43.9 10.7 10.21 10.01 86.41
03 68 20.4 53.9 00.7 00.21 69.9 36.41
53 59 30.4 63.9 99.6 99.11 29.9 06.41
04 401 40.4 73.9 89.6 89.11 88.9 65.41
54 311 50.4 83.9 89.6 89.11 58.9 35.41
05 221 60.4 93.9 89.6 89.11 28.9 15.41
55 131 70.4 04.9 89.6 89.11 97.9 84.41
06 041 90.4 14.9 89.6 89.11 77.9 64.41

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ORP CALIBRATION (HI 8615 family)
INITIAL PREPARATION
Disconnect the +ve supply cable from the “+VE LOOP” terminal
and connect a 20 mA f.s. ammeter between the +ve cable and the
“+VE LOOP” terminal. With HI 8615L the instrument display can
be used during calibration without the need to connect the ammeter.
In this case the values are directly expressed in mV units.
Pour a small quantity of HI 7020 ORP solution
into a beaker.
PROCEDURE
•Connect the shorting BNC connector
to the ORP transmitter.
•Adjust the OFFSET ADJUSTMENT
trimmer on the module for
a display of 12 mA on the
ammeter or 0 mV on the
instrument display (HI 8615L
only). This sets the zero point for the transmitter.
•Connect the ORP electrode to
the transmitter and immerse
the tip of the electrode into
a beaker of HI 7020 ORP
calibration solution, and check
that the ammeter reading lies
between 13.6 and 14.2 mA
for HI 8615 or the instrument
reading is between 200 and
275 mV at 25°C (HI 8615L).

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•If the reading lies outside this range,
adjust the slope adjustment trimmer
on the transmitter for a reading just
within this range.
The unit is now calibrated.
A complete calibration of the transmitter
module is advised periodically.
This calibration procedure requires the HI 8427 or the HI 931001 pH
and ORP simulator to simulate the ORP electrode.
HI 8427 or HI 931001 produce a known signal into the system so
that the faults of the system can be isolated.
•Connect the ORP transmitter to the simulator.
•Set the simulator to 0 mV and adjust the offset trimmer to read
12 mA on the ammeter or 0 mV on the HI 8615L display.
•Set the simulator to 350 mV and adjust the slope trimmer to
read 14.8 mA for HI 8615 on the ammeter or 350 mV on the
HI 8615L display.

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FOR HI8615L ONLY
The HI 8615L are factory calibrated, and the displayed values are
referenced to the 4-20 mA loop current. Under normal application,
adjustment on this module may not be necessary. If routine check is
required, the following procedures shall be performed.
•Follow the above procedure for HI 8615 (see page 13).
•Simulate a 12.00 mA loop current for the transmitter (i.e. 0 mV
at Electrode input) and check display reading.
•Simulate a 20.00 mA loop current for the transmitter (e.g.
+1000 mV for HI 8615L at Electrode input) and check display
reading.
•Connect the ORP electrode to the module and immerse the tip of
the electrode into the beaker of HI 7020 ORP solution and check
that the ammeter reading lies between 13.6 and 14.2 mA for
HI 8615, or the instrument reading is between 200 and 275mV
at 25 °C (HI 8615L only).
•Only if the reading lies outside this
range, adjust the slope adjustment
trimmer on the transmitter to reflect
a reading within this range.

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Please note:
HI 8615 or HI 8615L
-1000 mV =4 mA
0 mV =12 mA
1000 mV =20 mA
350 mV =14.8 mA
200 mV =13.6 mA
275 mV =14.2 mA
1 mV =12.008 mA
Note:When the HI 8615 and HI 8615L are used in conjunction
with the Hanna new HI 8512 indicator or HI 8720 controller,
the calibration can also be performed on the indicator/
controller. In this case slight adjustment can be made on the
indicator/controller even if the whole system calibration is
advised, always starting from the transmitter.

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ELECTRODE CONDITIONING
& MAINTENANCE
PREPARATION PROCEDURE
Remove the protective cap.
DO NOT BE ALARMED IF ANY SALT DEPOSITS ARE PRESENT.
This is normal with electrodes and they will disappear when rinsed
with water.
During transport tiny bubbles of air may have formed inside the glass
bulb. The electrode cannot function properly under these conditions.
These bubbles can be removed by "shaking down" the electrode as
you would do with a glass thermometer.
If the bulb and/or junction are dry, soak the electrode in HI 70300
storage solution for at least one hour.

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For refillable electrodes
If the fill solution (electrolyte) is more than 1cm (½") below the fill
hole, add HI 7082 3.5M KCl electrolyte solution for double junction or
HI 7071 3.5M KCl+AgCl electrolyte solution for single junction
electrodes. For a faster response unscrew the fill hole screw during
measurements.
For AmpHel®electrodes
If the electrode does not respond to pH changes, the battery is run
down and the electrode should be replaced.
MEASUREMENT
Rinse the electrode tip with distilled water.
Immerse the tip (4 cm / 1½") in the sample and stir gently for
approx. 30 seconds.
For a faster response and to avoid cross contamination of the samples,
rinse the electrode tip with a few drops of the solution to be tested,
before taking measurements.
STORAGE
To minimize clogging and assuring a quick response time, the glass
bulb and the junction should be kept moist and not allowed to dry
out. Replace the solution in the protective cap with a few drops of
HI 70300 storage solution or, in its absence, filling solution (HI 7071
for single junction or HI 7082 for double junction electrodes). Follow
the Preparation Procedure above before taking measurements.
Note:NEVER STORE THE ELECTRODE IN DISTILLED WATER OR DRY.
PERIODIC MAINTENANCE
Inspect the electrode and the cable. The cable used for connection to
the meter must be intact and there must be no points of broken
insulation on the cable or cracks on the electrode stem or bulb.
Connectors must be perfectly clean and dry. If any scratches or cracks
are present on the electrode body, replace the electrode. Rinse off any
salt deposits with water.
For refillable electrodes
Refill it with fresh electrolyte (HI 7071 for single junction or HI 7082
for double junction electrodes). Allow the electrode to stand upright for
1 hour.
Follow the Storage Procedure above.

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TROUBLESHOOTING
Evaluate your electrode performance based on the following.
••
••
•Noise (Readings fluctuate up and down) could be due to:
--
--
-Clogged/Dirty Junction: refer to the Cleaning Procedure
above.
--
--
-Loss of shielding due to low electrolyte level (in refillable
electrodes only): HI 7071 for single junction or HI 7082 for
double junction electrodes.
••
••
•Dry Membrane/Junction: soak in HI 70300 storage solution for
at least one hour.
••
••
•Drifting: soak the electrode tip in warm Hanna solution HI 7082
for one hour and rinse the tip with distilled water. Refill with fresh
HI 7071 for single junction electrodes and HI 7082 for double
junction electrodes.
••
••
•Low Slope: refer to the Cleaning Procedure above.
••
••
•No Slope: check the electrode for cracks in glass stem or bulb and
replace the electrode.
••
••
•Slow Response/Excessive Drift: soak the tip in Hanna HI 7061
cleaning solution for 30 minutes, rinse thoroughly in distilled
water and then follow the Cleaning Procedure above.
CLEANING PROCEDURE
•General Soak in Hanna HI 7061 general cleaning solution
for approximately 1 hour.
Removal of films, dirt or deposits on the membrane/junction:
•Protein Soak in Hanna HI 7073 protein cleaning solution
for 15 minutes.
•Inorganic Soak in Hanna HI 7074 inorganic cleaning solution
for 15 minutes.
•Oil/grease Rinse with Hanna HI 7077 Oil & Fat cleaning
solution.
IMPORTANT: After performing any of the cleaning procedures rinse
the electrode thoroughly with distilled water, drain and refill the
reference chamber with fresh electrolyte, (not necessary for GEL filled
electrodes) and soak the electrode in HI70300 storage solution for at
least 1 hour before taking measurements.

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Since the resistance of the pH electrode is in the range of 50-200
Mohm, the current across the membrane is in the pico Ampere range.
Large currents can disturb the calibration of the electrode for many
hours.
For these reasons high humidity environments, short circuits and static
discharges are detrimental for a stable pH reading.
The pH electrode's life also depends on the temperature. If constantly
used at high temperatures, the electrode life is drastically reduced.
TEMPERATURE-RESISTANCE CORRELATIONTEMPERATURE-RESISTANCE CORRELATION
TEMPERATURE-RESISTANCE CORRELATIONTEMPERATURE-RESISTANCE CORRELATION
TEMPERATURE-RESISTANCE CORRELATION
FOR HANNAFOR HANNA
FOR HANNAFOR HANNA
FOR HANNA pp
pp
pH SENSITIVE GLASSH SENSITIVE GLASS
H SENSITIVE GLASSH SENSITIVE GLASS
H SENSITIVE GLASS
The resistance of glass electrodes partially depends on the temperature.
The lower the temperature, the higher the resistance. It takes more
time for the reading to stabilize if the resistance is higher. In
addition, the response time will suffer to a greater degree at
temperatures below 25 °C (77 °F).
Typical Electrode Life
Ambient Temperature 1 –3 years
90 ºC Less than 4 months
120 ºC Less than 1 month
TEMPERATURE CORRELATION
FOR pH SENSITIVE GLASS