Hanna Instruments HI7640-18 Series User manual

INSTRUCTION MANUAL
HI7640-18 Series
Galvanic Dissolved Oxygen
Industrial Smart Probe
dedicated to HI510 Process Controller
HI7640-1805
SN: XXXXXXXXXXXX
0 to 50 ppm (mg/L)
T: −5 to 50 °C
pmax: 3 bar

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.
Thank you for choosing a Hanna Instruments product.
Please read this instruction manual carefully before using this
instrument.
This manual will provide you with the necessary information for
correct use of this instrument, as well as a precise idea of its
versatility.
If you need additional technical information, do not hesitate to
e‑mail us at [email protected] or view our contact list at
www.hannainst.com.
Dear
Customer,

3
TABLE OF CONTENTS
TABLE OF CONTENTS
1. Preliminary Examination ......................................................................... 4
2. Safety Measures .................................................................................... 4
3. General Description ................................................................................ 4
4. Main Features ........................................................................................ 5
5. Specifications ........................................................................................ 5
6. Preparing for Use ................................................................................... 6
7. Installation ............................................................................................ 6
8. Wiring the Probe to the Controller ............................................................ 8
9. Calibration ............................................................................................ 9
10. Maintenance ....................................................................................... 9
11. Accessories ........................................................................................ 10
Certification .............................................................................................. 11
Recommendations for Users ....................................................................... 11
Warranty .................................................................................................. 11

4
PrELimiNAry ExAmiNATiON
1. PRELIMINARY EXAMINATION
Remove the probe from the packing and examine it carefully.
Each galvanic dissolved oxygen probe is supplied with:
• HI7042S Refilling electrolyte solution, 30 mL
• HI76409A/P Replacement membrane (5 pcs.)
• Refilling pipette
• Replacement screw and o-ring for electrolyte refilling
• Protective cap
• Probe quality certificate and Instruction manual
Note: Save all packing material until you are sure that the probe works
correctly. Any damaged or defective item must be returned in its original
packing material with the supplied accessories.
2. SAFETY MEASURES
General Safety & Installation Recommendations
• Electrical connection, installation, operation, and maintenance must be
carried out by specialized personnel only.
The specialized personnel must read, understand, and adhere to the
instructions in this manual.
• Before connecting the probe to the process controller, disconnect the
controller from the power line.
• User serviceable connections are all accessible inside controller’s enclosure.
• Before powering the controller, verify the probe wiring has been done
following the detailed instructions in this manual.
3. GENERAL DESCRIPTION
The HI7640-18 is a galvanic-style oxygen probe series designed for use with the
Hanna Instruments HI510 Universal Process Controller.
The probe is suited for continuous measurement of oxygen dissolved in water.
An integral temperature sensor measures water temperature and adjusts the probe
signal over the specified temperature range. The result is reliable dissolved oxygen
(DO) concentration or percent saturated measurements.
Suitable for control applications in municipal and industrial wastewater treatment, the
probe can be installed directly in-line, immersed in a tank, or in a flow cell installation.
The galvanic probe functions in the same manner as a battery. The sensing
elements consist of silver cathode and zinc anode, with a pretensioned HDPE
membrane isolating the cell from the liquid being measured.
O-ring seal
Membrane cap
Oxygen permeable
membrane
Zinc anode element
Silver cathode element
The refillable electrolyte reservoir holds ample electrolyte to support the reaction.
Oxygen diffuses through the membrane and is reduced on the surface of the
cathode. This reaction generates a signal proportional to the oxygen concentration.
Note on manual: Refer to the HI510 controller manual for Probe Setup options
regarding measurement, calibration, and control settings.

5
mAiN FEATurES
4. MAIN FEATURES
• Galvanic probe with digital processing
• Simple membrane-cap replacement using pretensioned HDPE membranes
• Large electrolyte reservoir provides longer service life
• Rugged, chemically-resistant PVDF (Kynar®) body
• 3/4” NPT external thread for mounting
• 3 bar maximum pressure
• Built-in temperature sensor for measurement and DO compensation
• Digital probe stores model, firmware, serial number, and calibration information
5. SPECIFICATIONS
Range 0.0 to 600.0 % saturation
0.00 to 50.00 mg/L (ppm) concentration
Accuracy ±2 % of reading ±1 digit
Temperature –5.0 to 50.0 °C (23.0 to 122.0 °F)
Temperature accuracy ± 0.5 °C / 1.0 °F
Temperature
compensation –5.0 to 50.0 °C (23.0 to 122.0 °F)
Body PVDF
Sensor type
Galvanic cell
• Cathode: Silver (Ag)
• Anode: Zinc (Zn)
Water movement 0.01 to 0.03 m/second
Maximum pressure 3 bar
Threaded connection 3/4” NPT external thread for insertion mounting
Wetted parts
Sensor body
Membrane cap
Membrane material (HDPE)
O-ring
Cable length 5 m (16’5”)
Dimensions
HI7640-1805
SN: XXXXXXXXXXXX
0 to 50 ppm (mg/L)
T: −5 to 50 °C
pmax: 3 bar
197 mm (8”)
52.6 mm (2”)
Ø 28.4 mm (1.1”)
3/4’’ NPT (27 mm)
Probe Configuration
HI7640 –1 8 z z
1Galvanic sensor
8 Smart probe, with RS485 connection
zz
00, 05, 10, 15, 25, 50 attached cable length (meters)
The HI7640-1800 is supplied without cable.
See Accessories section for extension cable ordering codes.

6
PrEPAriNg FOr uSE
6. PREPARING FOR USE
Galvanic dissolved oxygen probes from Hanna Instruments are shipped dry. Remove
the red and black shipping cap before use.
The membrane and the probe need to be filled with HI7042S Galvanic dissolved
oxygen electrolyte solution prior first use and after membrane replacement.
Electrolyte must be replaced periodically, approximately once every 6 to 8 months.
The membrane cap should be replaced at the same time that the probe is refilled
with electrolyte.
Fill hole
Screw
Ø 3 mm o-ring
Shipping cap
Ø 15 mm o-ring
O-ring position Membrane cap
1. Unscrew and remove fill hole screw and o-ring located on side of probe body
(see figure). Set aside.
2. Open the membrane package and take one Ø 15 mm sealing o-ring and
one membrane cap.
3. Slide o-ring over anode and up onto cap threads, flushed against body. See
figure for correct o-ring position.
4. Rinse the new membrane cap with some electrolyte and discard.
5. Fill the membrane cap with electrolyte.
6. Tap the cap to release any trapped air bubbles. Allow them to rise to the surface.
7. Refill cap to the top.
8. Holding the sensor at a slight angle with the fill hole aligned upright, slowly
insert the sensing tip into the membrane cap so excess electrolyte and any
remaining trapped air escapes through the fill hole.
9. Screw the membrane cap onto sensor body.
10. Use supplied pipette to fill the probe reservoir with electrolyte solution.
The sensor holds approximately 8 mL of electrolyte.
11. Replace the Ø 3 mm o-ring and screw into the fill hole and tighten the screw.
7. INSTALLATION
General considerations
• Probes are easily installed using the 3/4” NPT external thread on the probe.
• Do not install the probe in an upside-down position.
• Hand tighten the probe in position. Then, depending on the process, tighten
one or two turns with a wrench to secure in place.
• The membrane should stay wetted at all times as the probe consumes oxygen.
• Regardless of installation type (tube, tank, or flow cell) ensure an adequate
water movement of 0.01 to 0.03 m/second past the sensor using a recirculating
pump or a tank mixer.
• If placing the probe into a stream or fast flowing waters it is best to place it
perpendicular to the flow and not facing into the flow.
• Provisions must be made for the removal of the probe from the process.
Consider probe accessibility for maintenance.
• Make sure the membrane is protected from any blunt objects and is kept clean,
to allow free exchange of oxygen.

7
iNSTALLATiON
Possible installation schemes with the relevant mounting accessories
Note: Due to the flexible nature of this product, accessories necessary to match
desired configuration must be purchased separately, such as the accessories
mentioned in this manual.
In-line mounting
with probe saddle
Tank immersion
with electrode holder
1
2
4
3
5
1
2
4
3
5
6
9
8
7
1 Probe
2 Probe fitting kit
3 Saddle
4 Membrane cap
5 Pipe
1 Probe cable
2 Cable locking system
3 Pipe cap
4 Adjuster
5 PVC pipe
6 Probe body
7 O-ring, Ø 22.2 mm (0.87”)
8 Membrane cap
9 Protective end cap
When installing the probe into the immersion electrode holder:
1. Screw the probe into the holder’s threaded end cap (9)
2. Run the probe’s extension cable through the pipe cap opening (3)
3. Screw the subassembly onto the PCV pipe (5)
4. Tighten the cable locking system (2) to secure the cabling
When removing the probe from tank (fish tank, water-treatment tank) or saddle
and installing in a flow cell, users must consider that water characteristics change,
as well as pressure or temperature, giving different dissolved oxygen readings
when taking measurements.
Flow-cell installation
• Ensure no strong flow velocity past the membrane to maintain membrane
integrity and prevent unstable readings. Placing the probe in a weir is
recommended in extremely turbulent aeration basin installations.
• Position the probe so that it does not trap air bubbles at the membrane cap.
• Adjust the flow rate to around 150 L/hour (40 gal./hour) in order to provide
the DO sensor with the required water movement of 0.01 to 0.03 m/second.
• Deposits of foreign material should not accumulate within the membrane area.

8
WiriNg ThE PrOBE TO ThE CONTrOLLEr
RECIRCULATION
PUMP
FILTER
FLOW
DETECTOR
(OPTIONAL)
TANK
MEASURE
FLOW
VALVE 1
VALVE 2
FLOW
EXIT FLOW
INCOMING FLOW
FLOW CELL
3
12
4
5
6
7 8 9 10
6
1 Process controller
2 Wiring cable
3 DO probe
4Flow-cell adapter
5 Flow cell
6Valves to control flow-cell flow
7 Measure flow
8 Filter
9 Recirculation pump
10 Saddle for pipe, 1¼” thread
8. WIRING THE PROBE TO THE CONTROLLER
1. Run the probe cable through the conduit opening.
2. Connect the probe leads to the removable terminal connector marked PROBE.
Follow the lead markings (+) positive / (–) negative, to ensure correct
wiring position for output leads.
3. Carefully put the wired terminal connector into place on the board.
4. Position the excess cable through the cable gland, before tightening the nut.
5. Remove the ground screw and hardware located below the PROBE connector
and attach ground lead ( ).
COMM
-BA+
IN1 IN2 A01 A02 A03 A04
PROBE
-BA+
PROBE
-BA+
A+
B
—

9
CALiBrATiON
Probe Cabling Color Code
Marking Color Functionality
– GREEN 0V
B WHITE RS485 D –
A YELLOW RS485 D+
+ BROWN 5V
GREEN / YELLOW PROTECTIVE GROUND CONNECTION
9. CALIBRATION
HI510 Controller allows two types of DO calibration procedures:
• Standard calibration − a two-point calibration with standards
• Process calibration − available only if the probe has been calibrated in
standards previously
Standard Calibration
Preparation
A two point calibration with standards verifies the probe is working correctly and
establishes a slope.
• Verify the probe is filled with electrolyte and is connected to the controller.
• Verify the controller’s barometric pressure reading with a reference meter. The
pressure value can be adjusted from the controller’s Technical Menu.
• Set the Salinity value if probe will be exposed to ocean or brackish waters.
• Set controller to desired measurement unit. Go to Probe Setting in Channel
Setup. Choose between DO_Sat (% saturation) or DO_Conc (Concentration).
Procedure
A two point calibration uses air and zero oxygen solution to calibrate.
1. Press MENU direct key ( ) then CAL virtual key. The controller recognizes
the currently selected measuring unit.
2. Suspend the probe into the water-saturated air and wait for the probe to
reach thermal equilibrium.
3. Press CFM when displayed followed by Next.
4. Submerge the probe into HI7040 Zero oxygen solution and stir gently for
2-3 minutes. Wait for the temperature and probe values to become stable.
The meter will automatically recognize the 0% (ppm) standard.
5. Press CFM to confirm the second calibration point and save the calibration.
Process Calibration
A process calibration is a single point calibration performed with the probe
installed in the process. This type of calibration allows the user to adjust the
measured DO value so that it matches the value determined with the hand-held
meter. Prior to performing a process calibration, a hand-held meter and probe
must be used to determine the DO value of the process.
Preparation
• Determine the process DO value, using a calibrated portable meter and probe.
• The process controller and the probe should have previously been calibrated
with two standards (so a probe slope has been determined).
Procedure
1. Press MENU direct key ( ) then CAL virtual key.
2. Press Process when it is displayed.
3. Adjust the process value in agreement with the predetermined value using the
directional keys ( ). Press CFM to confirm and save the calibration.
10. MAINTENANCE
DO Probe & Cap Membrane Cleaning
• Inspect, clean, and calibrate the probe at regular intervals. Alternatively, follow
Standard Operating Procedures (SOP) guidelines.
• Rinse the probe, with cap assembled, with clean water. Blot the probe with a
soft cloth or tissue. Handle the probe and membrane carefully to avoid damage.

10
ACCESSOriES
MAN7640-18 06/21
• Mechanical cleaning of the membrane with abrasives is not recommended.
• Clean the exterior of the probe by wiping with a aqueous-soapy mixture and
gently rubbing persistent spots off. Rinse with clean water.
• Replace the cap and electrolyte if coating persists or membrane damage is evident.
Membrane Cap & Electrolyte Replacement
The membrane cap and electrolyte are designed to provide trouble-free operation
for up to eight weeks. Replacements are required when:
• The membrane cap is physically damaged
• Probe response is slower than usual, especially after many months of use
• DO probe calibration or readings exhibit greater than normal drift, especially
after many months of use
• The membrane cap remains fouled after cleaning procedures were implemented.
Procedure
1. Remove probe from installation.
2. Unscrew and remove electrolyte screw located on the side of the probe body.
3. While holding the probe assembly vertical, unscrew the membrane cap
assembly from the probe body. Discard the old membrane cap assembly. To
remove old electrolyte, shake probe down.
4. Flush the probe body and electrolyte reservoir with tap water. Dry assembly
with a lint-free cloth or tissue.
5. Inspect O-rings for nicks or wear. Discard and replace damaged ones.
6. If tarnished or stained, gently clean the cathode with a lint-free cloth.
7. Follow section 6 of this manual for filling instructions.
Long Term Storage
Discard any electrolyte solution from the reservoir and flush probe body and
reservoir with water. Store the probe with the protective cap on.
11. ACCESSORIES
Ordering Information Product Description
DO Solutions
HI7040L Zero oxygen solution set, 500 mL + 12 g
HI7042S Refilling electrolyte solution, 30 mL
Other Accessories
HI60501 PVC immersion electrode holder
HI60501-0 O-rings for HI60501 electrode holder
HI605011 PVC mounting flange for HI60501 electrode holder
HI60503 PVDF immersion electrode holder
HI60542 In-line electrode holder, direct pipe installation
HI740155P Electrode refilling capillary pipette (20 pcs.)
HI76510-05 Probe extension cable, 5 m (16’5”) long
HI76510-10 Probe extension cable, 10 m (32’9”) long
HI76510-15 Probe extension cable, 15 m (49’2”) long
HI76510-25 Probe extension cable, 25 m (82’) long
HI76510-50 Probe extension cable, 50 m (164’) long
BL120-400 Flow-cell probe adapter kit
BL120-401 Flow-cell valve
BL120-402 Flow-cell tubing,10 m (32’8”) long
BL120-410 Flow cell
BL120-450 Flow-cell kit for Ø 50 mm (2”) pipe
BL120-463 Flow-cell kit for Ø 63 mm (2.5”) pipe
BL120-475 Flow-cell kit for Ø 75 mm (3”) pipe
BL120-500 Probe fitting kit
BL120-550 Probe saddle for Ø 50 mm (2”) pipe, 1¼” thread
BL120-563 Probe saddle for Ø 63 mm (2.5”) pipe, 1¼” thread
BL120-575 Probe saddle for Ø 75 mm (3”) pipe, 1¼” thread
For additional accessories information contact your local sales office.