Hanna Instruments ORP Electrode for HI98120 (HI73120)

Hanna Instruments ORP electrode for HI98120 (HI73120)

The HI73120 is a replacement ORP (redox) electrode for the Hanna Instruments HI98120 pocket ORP tester. It screws directly onto the tester body and carries the platinum sensing element that measures the oxidation-reduction potential of pool and spa water. Supplying the electrode separately means a worn sensor can be renewed without replacing the complete meter.

What it fits

This electrode is designed specifically for the Hanna Instruments HI98120 pocket ORP tester. It is not a universal ORP probe and is not intended for bench meters or panel-mounted controllers with BNC connections. Confirm your tester model on the housing before ordering.

Fitting the electrode

Unscrew the used electrode from the base of the tester and remove it together with its sealing ring. Screw the new HI73120 into place hand-tight so the seal seats evenly and the housing stays watertight. Rinse the platinum tip with clean water, then check the reading against an ORP test solution before returning the tester to service.

Service life

ORP electrodes are consumables: the platinum surface fouls and the reference junction ages with use. Replace the electrode when readings drift, respond slowly, or can no longer be confirmed against a known ORP test solution. Storing the tip wet in storage solution and never letting it dry out gives the longest usable life.

Ordering notes

Sold individually as a single electrode, not as a kit with test or storage solution. Order calibration and storage solutions separately if you do not keep them in stock. Keep a spare electrode on hand so a failing sensor does not interrupt routine pool water checks.