Advanced Dissolved Oxygen Meter with Optical DO Probe (opdo®)
HI6421 includes Hanna’s HI7641133 optical dissolved oxygen probe (opdo®) that is based on the principle of fluorescence quenching. An immobilized Pt-based luminophore is excited by the light of a blue LED and emits a red light. As oxygen interacts with the luminophore it reduces the intensity and lifetime of the luminescence. The lifetime of the luminescence is measured by a photodetector and is used to calculate the dissolved oxygen concentration.
The probe is fitted with easy-to-use Smart Caps (HI764113-1) which lock in place and contain pre-loaded calibration coefficients that are automatically transmitted to the probe. The Smart Cap features an immobilized O₂ sensitive luminophore with a rugged insoluble black oxygen permeable protective layer.
Over time, the sensor’s optical components can age but are compensated for by using the reference signal to compensate for the measuring path. As a result, the sensor provides accurate DO measurements over long periods of time without the need for frequent calibration.
Advanced Dissolved Oxygen Meter with Polarographic DO Probe
HI6421P includes the HI764833 polarographic probe. Slim and versatile, this probe covers a wide range of dissolved oxygen and has a built-in thermistor temperature sensor that compensates for temperature variations. The slim design allows for convenient measurement in test tubes and Biological Oxygen Demand (BOD) bottles.
Durable and robust, the probe features a platinum cathode and Ag/AgCl anode assembly. Accurate and with a fast response time, readings are not flow dependent.
The probe is fitted with durable (PTFE), oxygen permeable, screw on membrane caps. Caps are filled with electrolyte and easily installed on the probe.
Concentration measurements are automatically compensated for barometric pressure, temperature, and salinity. Barometric pressure and temperature are automatically measured and compensated. Salinity is automatically compensated by setting manually the salinity concentration of the water being measured.
Pressure compensation is done automatically (built-in barometer) or users have the option to manually enter required value. Pressure is displayed in user-configurable units: mmHg, mbar, kPa, inHg, psi, atm.
User Interface
- 7-inch capacitive touch screen with multi-touch support
- Capacitive touch back, home and system menu keys
- User-friendly icons and symbols allow users to easily navigate and interpret the instrument functions.
Five Intuitive Views
- Basic measurement configuration
- Simple GLP with calibration information
- Full GLP with electrode status and calibration point details
- Live updated, interactive graph
- Tabulated data with date, time, and notes
Measurement
- Application-specific profiles allow quick and direct measurement without the need to update the sensor and system settings
- Active log during measurement
- Measurement stability indicator (using the Stability Criteria setting)
- Reading modes: direct and direct/autohold
- Temperature compensation can be automatic or set manually
- Audible and/or alarm messages for measurements outside of predefined limits
- Galvanic isolation for measurement
Calibration
- One or two points calibration at 0% and/or 100% saturation
- Single point manual calibration in mg/L or % saturation using a reference method
- Non-volatile memory saves data and settings
Zero Oxygen Calibration Solution
When performing a DO calibration, it is important that the correct standards are used. We include some starter solution to get you going. HI7040L is a bi-component zero oxygen solution designed so you can quickly calibrate to 0% oxygen concentration.
Logging
- Data log collection of up to 1,000,000 data points (with time and date stamp)
- Logging types: manual, automatic, autohold
- Sample ID for manual and autohold data
Connectivity Features & Services
- Transfer logged data to a USB thumb drive
- Log files that include measurements and calibration data (as .csv file)
- FTP and email for log export via Ethernet and Wi-Fi connection
- USB type A for USB stick, keyboard, and printer
- USB type C for USB stick and PC connection
Help Section for Meter Guidance
- Video support presentation of main functionalities
Smart Cap Technology
Automatic Cap Recognition
Hanna’s Smart Caps feature a built-in RFID reader that is able to store important data, including manufacture date and first-use date for increased traceabilty.
Longer Life
Smart Caps last one year from the date of first use. Your meter will automatically count down from initialization and will have your meter remind you when it has expired with an on-screen message.
Aligned Right Every Time
An alignment key ensures that your Smart Cap is on correctly every time.