Advanced Dissolved Oxygen Benchtop Meter

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 O? sensitive luminophore with 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 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)