HI6421 is a streamlined dissolved oxygen benchtop meter supplied with Hanna’s optical dissolved oxygen
HI6421 is a streamlined dissolved oxygen benchtop meter supplied with Hanna’s optical dissolved oxygen
The HI6421 is a user-friendly benchtop meter with a large touchscreen display, designed for both fresh and saltwater dissolved oxygen measurements. It features a durable housing and an integrated module tailored for accurate readings.
The HI6421 is paired with Hanna’s HI7641133 optical dissolved oxygen probe (opdo®), which operates based on fluorescence quenching principles. A Pt-based luminophore, immobilized within the probe, is excited by a blue LED light and emits red light. When oxygen interacts with the luminophore, it reduces the intensity and duration of the luminescence. This decrease in luminescence lifetime is detected by a photodetector and used to calculate the dissolved oxygen concentration.
The probe comes equipped with Smart Caps (HI764113-1), which are easy to attach and feature pre-loaded calibration coefficients that are automatically transferred to the probe. These Smart Caps contain an immobilized oxygen-sensitive luminophore, protected by a robust black, oxygen-permeable layer. Though the optical components of the sensor may age over time, the reference signal compensates for this, ensuring accurate long-term DO measurements without the need for frequent recalibration.
In addition to standard dissolved oxygen measurements, the HI6421 includes built-in methods and calculations for Biological Oxygen Demand (BOD), Oxygen Uptake Rate (OUR), and Specific Oxygen Uptake Rate (SOUR). Pressure compensation is automatic, thanks to an integrated barometer, or users can manually input the required value. Pressure is displayed in user-configurable units, including mmHg, mbar, kPa, inHg, psi, and atm.
Caractéristiques
| DO (HI7641133 Optical probe) Range | 0.00 to 50.00 mg/L (ppm) concentration; 0.0 to 500.0 % saturation |
| DO (HI7641133 Optical probe) Resolution | 0.01 mg/L (ppm); 0.1 % saturation |
| DO (HI7641133 Optical probe) 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 |
| 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 |
| Barometric Pressure Resolution | 1 mmHg; 1 mBar; 1 kPa; 1 inHg; 0.1 psi; 0.001 atm |
| Barometric Pressure 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 |
| Temperature Resolution | 0.1 °C; 0.1 °F; 0.1 K |
| Temperature Accuracy | ±0.2 °C; ±0.4 °F; ±0.2 K |
| DO Calibration Points | 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 Calibration Standards | 0 and 100% saturation |
| DO Calibration Reminder | Disabled Daily: 0 m in. to 23 hours and 59 m in. Periodic: 1 m in. to 500 days, 23 hours and 59 m in. |
| Temperature Compensation | Automatic or Manual |
| Salinity Compensation | 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 |
| Reading Stability criteria | Accurate Medium Fast |
| Reading Isopotential | 7.000 or 4.010 |
| Reading Sampling rate | 1000 ms |
| DO Views Basic | Measurement (DO, Temperature) Stability status |
| DO Views Simple | GLP Basic view information Last calibration date, offset, average slope |
| DO Views Full | GLP Simple GLP information and calibration point details |
| DO Views Table | Measurements updated every second are displayed in table |
| DO Views Graph (Plot) | Measurement versus time graph can be panned or zoomed (pinch-to-zoom technology) |
| Logging Type | Automatic, Manual, Autohold |
| Logging Number of records | 50 000 maximum per file Stores at least 1 000 000 data points per user |
| Logging Automatic interval | 1, 2, 5, 10, 30 seconds / 1, 2, 5, 10, 15, 30, 60, 120, 150, 180 minutes |
| Logging Sample ID | Incremental mode |
| Logging 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 |
| Connectivity USB-C | 1 port for PC connectivity and USB-C type thumb drive |
| Connectivity Wi-Fi & Ethernet | FTP / Web server Log transfer and download Email |
| Connectivity 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 | 1.2 kg (26.5 lbs.)1 |
| DO (HI7641133 Optical probe) Range | 0.00 to 50.00 mg/L (ppm) concentration; 0.0 to 500.0 % saturation |
| DO (HI7641133 Optical probe) Resolution | 0.01 mg/L (ppm); 0.1 % saturation |
| DO (HI7641133 Optical probe) 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 |
| 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 |
| Barometric Pressure Resolution | 1 mmHg; 1 mBar; 1 kPa; 1 inHg; 0.1 psi; 0.001 atm |
| Barometric Pressure 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 |
| Temperature Resolution | 0.1 °C; 0.1 °F; 0.1 K |
| Temperature Accuracy | ±0.2 °C; ±0.4 °F; ±0.2 K |
| DO Calibration Points | 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 Calibration Standards | 0 and 100% saturation |
| DO Calibration Reminder | Disabled Daily: 0 m in. to 23 hours and 59 m in. Periodic: 1 m in. to 500 days, 23 hours and 59 m in. |
| Temperature Compensation | Automatic or Manual |
| Salinity Compensation | 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 |
| Reading Stability criteria | Accurate Medium Fast |
| Reading Isopotential | 7.000 or 4.010 |
| Reading Sampling rate | 1000 ms |
| DO Views Basic | Measurement (DO, Temperature) Stability status |
| DO Views Simple | GLP Basic view information Last calibration date, offset, average slope |
| DO Views Full | GLP Simple GLP information and calibration point details |
| DO Views Table | Measurements updated every second are displayed in table |
| DO Views Graph (Plot) | Measurement versus time graph can be panned or zoomed (pinch-to-zoom technology) |
| Logging Type | Automatic, Manual, Autohold |
| Logging Number of records | 50 000 maximum per file Stores at least 1 000 000 data points per user |
| Logging Automatic interval | 1, 2, 5, 10, 30 seconds / 1, 2, 5, 10, 15, 30, 60, 120, 150, 180 minutes |
| Logging Sample ID | Incremental mode |
| Logging 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 |
| Connectivity USB-C | 1 port for PC connectivity and USB-C type thumb drive |
| Connectivity Wi-Fi & Ethernet | FTP / Web server Log transfer and download Email |
| Connectivity 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 | 1.2 kg (26.5 lbs.)1 |
