HANNA INSTRUMENTS HI98121 Electronic pH/Redox/°C Tester

The HI98121 tester from Hanna Instruments simultaneously measures pH , redox potential and temperature .
With its compact and perfectly waterproof case, the pH tester combines ease of use and measurement safety.
With the HI98121, it is possible to monitor both pH and ORP.
The HI98121 is commonly used to monitor pH and chlorine for many aquarium applications, including wastewater treatment.

By definition, pH is the measure of the voltage generated by an electrochemical cell at zero current. The potential generated is proportional to the measure of the thermodynamic activity of the ion.

Similar to a pH measurement that quantifies how acidic or alkaline solutions are, ORP (Oxidation Potential) measurements quantify the overall state of a solution as having the ability to oxidize or reduce a chemical species. Oxidizing and reducing reagents are used to participate in chemical reactions called ox redox reactions.
An ORP meter must be chemically inert; it cannot be oxidized or reduced itself. It must also have the appropriate surface characteristics to promote the rapid exchange of electrons, a property known as high exchange current density. Two noble metals have proven effective for this purpose: pure platinum and pure gold are both used in the construction of ORP sensors.

Technical specifications of the HI98121 tester:
• pH range: -2.00 to 16.00 pH
• pH resolution: 0.01 pH
• pH accuracy: ±0.05 pH
• pH calibration: Automatic in 1 or 2 points
• Redox range: ±1000 mV
• Redox resolution: 1 mV
• Redox accuracy: ±2 mV
• Temperature: -5.0 to 60.0°C
• Temperature accuracy: ±0.5°C
• Temperature compensation: automatic pH
• Power supply: 4 x 1.5V batteries; approximately 250 hours continuous auto-off after 8 minutes of non-use
• Dimensions: 163 x 40 x 26 mm
• Weight: 100 g

HANNA INSTRUMENTS HI98121 Package Contents:
• HI98121 (pHep®) is supplied in a box, with a protective cap
• Tool for replacing the probe
• 4 1.5 V button batteries
• Instruction manual.

Recommended calibration solutions for Hanna Instruments HI98121:
• HI7021M : 240 mV redox solution, 230 mL bottle
• HI7022M : 470 mV redox solution, 230 mL bottle
• HI7061M : General purpose cleaning solution, 230 mL bottle
• HI77400P : pH calibration kit, 5+5 sachets of pH4/pH7 of 20mL