Hanna sells this one under a name that states the spec outright: Checker pH Tester with 0.1 pH Resolution. Range is 0.0 to 14.0 and accuracy is plus or minus 0.2 pH at 25C. That is the honest number. If you need to see hundredths, this is not the meter. For a reservoir you are holding between 5.5 and 6.5, a tenth of a pH is the resolution the decision actually turns on. Over a million of these have gone out since 1991.
Calibration is automatic to one or two points. The HI98103 pH meter recognises the pH 4.01 and 7.01 buffers on its own, then tags the display with the values used. An hourglass sits on the screen until the reading settles, so you know when to write the number down. The HI1271 electrode is the part that wears, and it unscrews. A new one screws on and the meter body carries on. That electrode is 103 mm long and tapers to 8 mm at the tip, narrow enough for test tubes and vials. A CR2032 runs roughly 1,000 hours. Auto shut-off can be set to 8 minutes, 60 minutes, or turned off. The case holds meter, buffer sachets and cleaning solution together, which matters more than it sounds. A pH meter that lives loose in a drawer is a pH meter nobody calibrates.
Technical Specifications
| Specification | Value |
|---|---|
| Model | Hanna HI98103 Checker |
| pH Range | 0.0 to 14.0 pH |
| Resolution | 0.1 pH |
| Accuracy | +/- 0.2 pH at 25C / 77F |
| Calibration | Automatic, one or two point |
| Electrode | HI1271, replaceable, 103 mm long, 8 mm tapered tip |
| Battery | CR2032 lithium, approx 1,000 hours |
| Auto Shut-Off | 8 min, 60 min, or disabled |
| Dimensions | 50 x 174 x 21 mm (2 x 6.8 x 0.9 in) |
| Weight | 50 g (1.8 oz) |
| Operating Range | 0 to 50C (32 to 122F), up to 95% RH |
| Included | HI1271 electrode, pH 4.01 and 7.01 sachets, cleaning solution, battery, case, manual |
