HI-6421P includes the HI-764833 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.

Additional features include built-in methods and calculations for the measurement of BOD (Biological Oxygen Demand), OUR (Oxygen Uptake Rate), and SOUR (Specific Oxygen Update Rate).

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.
• The user can select between five different 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

• Measure %Sat, mg/L, ppm (DO); mg/L, ppm (BOD); mg/L (OUR); ppm, mg/L (SOUR)
• 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