The HI98121 is a lightweight ergonomically designed tester. This pH and ORP tester is designed to float making it ideal for taking ORP measurements virtually anywhere. With the HI98121 it is possible to monitor both pH and ORP at the same time. The HI98121 is commonly used to monitor pH and chlorine for many applications including swimming, food sanitization, plating wastewater treatment, and cooling tower water treatment.
By definition pH is the measurement of the voltage generated by an electrochemical cell at zero current. The potential generated is proportional to the thermodynamic activity of the ion being measured.
Similar to a pH measurement that quantifies the 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 known as a redox reaction.
An ORP meter must be chemically inert; it cannot be oxidized or reduced itself. It must also have the proper surface characteristics to promote rapid electron exchange, a property known as high exchange current density. Two noble metals have proven to work well for this purpose: pure platinum and pure gold are both used in the construction of ORP sensors.
Features at-a-glance:
- Waterproof
- Automatic Temperature Compensation
- HOLD feature
- Simple to use
- Economical
| Specification Name | Detail |
|---|---|
| SKU | HI98121 |
| pH Ranges | -2.00 to 16.00 pH |
| pH Resolution | 0.01 pH |
| pH Accuracy (@25°C/77°F) | ±0.05 pH |
| pH Calibration | automatic, one or two-point with two sets of standard buffers (pH 4.01 / 7.01 / 10.01 or 4.01 / 6.86 / 9.18) |
| pH Temperature Compensation | automatic for pH readings |
| ORP Range | ± 1000 mV |
| ORP Resolution | 1 mV |
| ORP Accuracy | ±2 mV |
| ORP Calibration | factory calibrated |
| Temperature Range | -5.0 to 60.0°C / 23.0 to 140.0°F |
| Temperature Resolution | 0.1°C / 0.1°F |
| Temperature Accuracy | ±0.5°C / ±1°F |
| pH Electrode | HI73127 replaceable pH electrode (included) |
| ORP Electrode | fixed ORP sensor |
| Automatic Shut-Off | auto-off after 8 minutes of non-use |
| Battery Type / Life | 1.5V (4) / approximately 250 hours of continuous use |
| Environment | -5 to 50°C (23 to 122°F); RH max 100% |
| Dimensions | 163 x 40 x 26 mm (6.4 x 1.6 x 1.0’’) / 100 g (3.5 oz.) |
| Ordering Information | Each HI98121 is delivered in a cardboard box and is supplied with: HI70004 pH 4.01 buffer solution, 20 mL sachet (1 pc.), HI70007 pH 7.01 buffer solution, 20 mL sachet (1 pc.), HI70300N Storage solution for pH & ORP electrodes, 20 mL sachet (1 pc.), HI70022 470 mV ORP test solution, 20 mL sachet (2 pcs.) , HI700601 pH & ORP electrode cleaning solution, 20 mL sachet (1 pc.), HI73127 pH electrode, HI73128 Electrode removal tool, 1.5V batteries (4 pcs.), instrument quality certificate, & instruction manual. |
| Warranty | 1 year |
