The HNHI2223 is a pH benchtop meter featuring Calibration Check™ diagnostics for both pH electrodes and buffer solutions during calibration. This instrument compares the characteristics of the pH electrode from one calibration to the next. In the case of large variances in the electrode condition, it alerts the user that the electrode needs to be properly cleaned prior to calibration and measuring. HNHI2223 also features five point calibration with seven standard buffers, Automatic Temperature Compensation and GLP capabilities that allow for the storage and retrieval of all data regarding pH. With a built-in logging function, measurements are stored in non volatile memory and can be transferred to a PC through the USB port. Users can manually log up to 200 records and interval log up to 500 records.