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HI-6421-02
The HI-6421 Advanced Benchtop Meter for Dissolved Oxygen is a laboratory-grade solution for the accurate measurement of DO, BOD, OUR and SOUR in both fresh and saltwater samples. This modern laboratory DO meter includes five different viewing modes, ethernet and WiFi connectivity and a comprehensive on-screen tutorial for ease-of-use.
HI-6421 Advanced Dissolved Oxygen Optical Benchtop Meter
The HI-6421 DO optical meter from Hanna Instruments provides an accurate and reliable laboratory-grade solution for measuring dissolved oxygen, oxygen uptake rate, specific oxygen uptake rate and biochemical oxygen demand in both freshwater and saltwater samples. This benchtop meter is equipped with an optical dissolved meter, while the HI-6421/P is supplied with a polarographic DO probe.
The HI-7641133 Opdo optical dissolved oxygen probe is included with the HI-6421. This probe is fitted with easy-to-use Smart Caps (HI-764113-1), which lock into place and contain pre-loaded calibration coefficients that transmit automatically to the probe. Each Smart Cap features an immobilised O2-sensitive luminophore within a rugged, insoluble black oxygen-permeable protective layer.
As the optical components of the sensor age, the measuring path is compensated with the reference signal. This ensures the HI-6421 DO benchtop lab meter provides accurate dissolved oxygen measurements over long periods without frequent calibration.
To book a demonstration of Hanna’s DO benchtop meters, or to discuss your requirements with knowledgeable specialists, get in touch with our experts today. Call on 01525 850 855 or email us at sales@hannainstruments.co.uk.
HI-6421 Laboratory DO Optical Meter Features
Space-saving, modern design
The HI-6000 series is designed to fit into modern laboratories, with a smaller footprint and simple design featuring a large, capacitive touchscreen that is functional even with gloves on. WiFi and ethernet connectivity and a flexible electrode arm allow the HI-6421 to be placed anywhere in the lab to save on space without reducing functionality.
Supplied with Hanna Opdo optical probe
Hanna’s HI-7641133 Opdo optical dissolved oxygen probe is supplied with the HI-6421 DO meter, based on the principle of fluorescence quenching. An immobilised Pt-based luminophore is excited by a blue LED light and emits a red light, which interacts with oxygen. The intensity and lifetime of the luminescence is measured by a photodetector in the opdo probe, which is then used to calculate the concentration of dissolved oxygen.
Flexible electrode holder
A Hanna electrode arm is included as standard with the HI-6421 benchtop DO meter, providing a secure hold for the opdo probe when measuring samples of salt or freshwater. This electrode holder can be mounted to either side of the body of the meter for greater flexibility.
Accurate, reliable and repeatable measurement
The HI-6421 provides accurate, reliable and repeatable measurements in a wide range of fresh and saltwater samples. This laboratory-grade benchtop meter ensures precision in testing for the measurement of DO (%Sat, mg/L, ppm), BOD (mg/L, ppm), OUR (mg/L) and SOUR (ppm, mg/L).
Flexible configuration and design
Digital connectivity with the option for both WiFi and ethernet means the HI-6000 series benchtop meters can be placed anywhere, with no restrictions for physical proximity to a printer or desktop PC. A configurable, flexible electrode arm is mountable on either side of the instruments allows the HI-6421 to fit into the available space in the lab.
Simple-to-use interface
Operation immediately out of the box is effortless, with a user-friendly interface and quick access to settings to set up and customise the HI-6421 to your requirements. The comprehensive menu system on this DO meter includes:
- Network
- Connect and Print
- System
- Custom Users
- User Account Management
- Info Screen
- Log Recall
- Log History and Sharing
- Log Detail
- On-Board Help
Five measurement view options
Tailor your measurement view to suit your needs with five individual options to choose from, each designed to meet a different requirement when measuring samples for dissolved oxygen:
- Basic View: A clean view featuring basic information about measurement
- Simple GLP View: Additional displays of GLP data, including Including latest calibration date and time, Offset value, average slope and electrode condition.
- Full GLP View: A complete GLP display featuring the electrode symbol and used buffers tray in addition to the above visuals.
- Graph View: A plotted graph from the active log of the current measurement
- Tabulated View: An organised table of data with date, time and notes in chronological order of testing.
Comprehensive data storage
Up to one million individual data points with time and date stamps can be stored within the HI-6000 series before transfer is required. Once exported via WiFi, ethernet, direct connection or USB stick this data is available in a universal .csv file format, with no additional software required for access.
Dual alarm system
Both audible and visual configurable alarms are available in the settings for the HI-6421 DO optical meter for labs, with the ability to configure the correct range for your samples. Measurements outside these ranges will trigger visual and/or audible alarms.
Remote transfer with ethernet and WiFi
The HI-6421 dissolved oxygen benchtop meter features WiFi and ethernet connectivity, allowing the transfer of data to any computer or email address via FTP or email log exports. These .csv files are accessible without the need to run the data through any software, providing excellent accessibility to remote labs, clients and other sites.
USB C and USB A support
Export data via USB stick with both USB A and C connection available on the HI-6421, allowing for the fast and easy transfer of data points as a universal .csv file. Peripherals such as keyboards can also be connected, as well as PCs, laptops and printers as required.
Video and text tutorial system
HI-6000 advanced meters include an on-screen, complete tutorial available as text and video through the HELP functionality. These instructions cover all of the main functionalities required to operate these lab-grade meters, allowing you to start measuring straight out of the box.
Customise and create users
Both administrator and standard users can be created on the HI-6421, providing full control over the configurations available to each user. Administrators are able to both create and manage other users from the Account Management Screen to limit or add permissions for day-to-day usage.
To book a demonstration or discuss your requirements for measuring DO with our experts, get in touch directly. Call us at 01525 850 855 or email us at sales@hannainstruments.co.uk to speak to our specialists.
FAQs
What instruments are in the HI-6000 range?
The HI-6000 range includes:
- HI-6221 pH and ORP meter
- HI-6321 Conductivity meter
- HI-6421 Dissolved Oxygen meter (also available with polarographic probe)
- HI-6000 Modular Multiparameter meter
Is the HI-6421 DO meter suitable for laboratory usage?
Every meter in the HI-6000 range, including the HI-6421 for DO, is specifically developed for use in laboratory-grade environments. This high-grade meter is suitable both for industries and businesses and for the laboratories that provide outsourced testing to their clients across a range of specialisations and niches.
What are the key features of the HI-6421?
Some of the key features of the Hanna HI-6421 include:
- Measures DO, SOUR, OUR and BOD
- Connect via WiFi and ethernet
- Easy-to-use interface
- Space-saving design
- Exceptional repeatability and accuracy
How do I order the HI-6421 benchtop DO meter?
You can buy the Hanna HI-6421 DO meter directly online at Hanna Instruments UK. If you would like to ask additional questions or would like expert guidance on the best dissolved oxygen meter for your requirement, contact our team directly at 01525 850 855 or email us at sales@hannainstruments.co.uk.
Can I get training on the HI-6421 meter?
In-built tutorials are available for all HI-6000 benchtop meters, with video and text options to provide information about how to operate our user-friendly instruments. If you require additional support or specific training, contact Hanna Instruments directly at 01525 850 855 or email us at sales@hannainstruments.co.uk.
What industries is the HI-6421 suitable for?
The HI-6421 optical benchtop meter for DO is a versatile instrument that is suitable for the measurement of both fresh and saltwater across a range of applications. This laboratory meter is beneficial for different industries that require the measurement of water and wastewater.
How do I book a demonstration with Hanna Instruments?
Call us on 01525 850 855 or email us at sales@hannainstruments.co.uk to book a demonstration with our team of experts and discuss your requirements for DO measurement instrumentation.
Read More
HI-6421 - DO (HI-7641133 Optical probe) | ||
Range | 0.00 to 50.00 mg/L (ppm) concentration; 0.0 to 500.0 % saturation | |
Resolution | 0.01 mg/L (ppm); 0.1 % saturation | |
Accuracy | from 0.00 to 20.00 mg/L (ppm) 1.5 % of reading or ±0.01 mg/L (ppm), whichever is greater from 20.00 to 50.00 mg/L (ppm) ±5 % of reading from 0.0 to 200.0 % saturation ±1.5 % of reading or ±0.1 %, whichever is greater from 200.0 to 500.0 % saturation ±5 % of reading | |
HI-6421P – DO (HI-764833 Polarographic probe) | ||
Range | 0.00 to 90.00 mg/L (ppm) concentration; 0.0 to 600.0 % saturation | |
Resolution | 0.01 mg/L (ppm); 0.1 % saturation | |
Accuracy | ±1.5 % of reading ±1, least significant digit | |
Barometric Pressure | ||
Range | 450 to 850 mmHg; 600 to 1133 mBar; 60 to 133 kPa; 17 to 33 inHg; 8.7 to 16.4 psi; 0.592 to 1.118 atm | |
Resolution | 1 mmHg; 1 mBar; 1 kPa; 1 inHg; 0.1 psi; 0.001 atm | |
Accuracy | ±3 mmHg within ±15 % from the calibration point ±3 mmHg ±1 least significant digit | |
Temperature | ||
Range | −20.0 to 120.0 °C −4.0 to 248.0 °F 253.0 to 393.0 K | |
Resolution | 0.1 °C; 0.1 °F; 0.1 K | |
Accuracy | ±0.2 °C; ±0.4 °F; ±0.2 K | |
DO Calibration | ||
Points | DO optical One or two points automatic calibration at 100% (8.26 mg/L) and 0% (0 mg/L). Single point manual using a value entered by the user in % saturation or mg/L. DO polarographic Automatic-two points / User standard-single point | |
Standards | 0 and 100% saturation | |
Reminder | Disabled Daily: 0 min. to 23 hours and 59 min. Periodic: 1 min. to 500 days, 23 hours and 59 min. | |
Temperature Compensation | Automatic or Manual | |
Salinity Compensation (Optical DO only) | Automatic from 0 to 70 PSU (manually set) 0.0 to 70.0 % / 0.0 to 45.0 g/L / 0.0 to 42.0 psu | |
Reading | ||
Modes | Direct Direct/Autohold | |
Stability criteria | Accurate Medium Fast | |
Isopotential | 7.000 or 4.010 | |
Sampling rate | 1000 ms | |
DO Views | ||
Basic | Measurement (DO, Temperature) Stability status | |
Simple GLP | Basic view information Last calibration date, offset, average slope | |
Full GLP | Simple GLP information and calibration point details | |
Table | Measurements updated every second are displayed in table | |
Graph (Plot) | Measurement versus time graph can be panned or zoomed (pinch-to-zoom technology) | |
Logging | ||
Type | Automatic, Manual, Autohold | |
Number of records | 50 000 maximum per file Stores at least 1 000 000 data points per user | |
Automatic interval | 1, 2, 5, 10, 30 seconds 1, 2, 5, 10, 15, 30, 60, 120, 150, 180 minutes | |
Sample ID | Incremental mode | |
Export option | .csv file format | |
Users | Up to 9 users and the default administrator account | |
Connectivity | ||
USB-A | 2 ports for keyboard input or USB thumb drive | |
USB-C | 1 port for PC connectivity and USB-C type thumb drive | |
Wi-Fi & Ethernet | FTP Web server Log transfer and download | |
RS232 | Connecting peripherals | |
Power supply | DC adapter 100-240AC to 24VDC 2.5A | |
Environment | 0 - 50 °C / 32 - 122 °F / 273 - 323 K maximum 95% RH non-condensing | |
Dimensions | 205 x 160 x 77 mm (8.0 x 6.2 x 3.0 “) | |
Weight | Approximately 1.2 kg (26.5 lbs.) | |
Ordering Information | HI-6421 is supplied with HI-7641133 optical dissolved oxygen probe (OPDO®); HI-764060 electrode holder; capillary pipette; 24 VDC power adapter; USB-C to USB-A cable; probe quality certificate; quick reference guide with instrument quality certificate. HI-6421P is supplied with HI-764833 polarographic probe; HI-764060 electrode holder; capillary pipette; 24 VDC power adapter; USB-C to USB-A cable; probe quality certificate; quick reference guide with instrument quality certificate. |