HANNA Instruments HI 98121 Waterproof pH-ORP-mV

Hanna Instruments
HI 98121
  • Description
  • More Details
  • Specifications


Range ±1000 mV
Range -2.00 to 16.00 pH
Range -5.0 to 60.0°C / 23.0 to 140.0°F
Resolution 1 mV
Resolution 0.01 pH
Resolution 0.1°C / 0.1°F
Accuracy ±2 mV
Accuracy ±0.05 pH
Accuracy ±0.5°C / ±1°F
Calibration factory calibrated
Calibration automatic, at 1 or 2 points with 2 sets of memorized buffers
(pH 4.01 / 7.01 / 10.01 or pH 4.01 / 6.86 / 9.18)
Temp. Compensation   Automatic for pH readings
Electrode   HI 73127 replaceable pH electrode (included); fixed ORP sensor
Battery Type/Life   4 x 1.5V with BEPS / approx. 250 hours of continuous use;
auto-off after 8 minutes of non-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.)

Not near as popular as the MW500 ORP meter a study seller in the ionized water community.  The Hanna instruments HI 98121 multi function portable pH and ORP meter can simultaneously do multiple measurements to measure negative oxygen reduction potential.

Be sure to always store your HI 98121 probe they went solution to maintain the best and most accurate results when testing negative ORP..  Check out our storage solution that we offer under the Milwaukee instruments link.


Specifications on the Hi98121

Supplemental Manual from

Hanna Instruments

negative ORP testing manual


The newest member to HANNA Combo series of combination waterproof testers with advanced functions is HI 98121, designed for simultaneous pH and ORP measurements.

HI 98121 also reads temperature, which is continuously displayed on the dual level LCD.

An encapsulated external stainless steel sensor, positioned in close proximity to the pH electrode provides fast response. A fiber junction can be easily pulled out and replenished. And when finally spent, the pH electrode cartridge can be quickly replaced with the supplied electrode removal tool, reducing waste and cost.

HI 98121 works with common batteries and when turned on, displays the percentage of remaining battery life. The stability indicator ensures reliable readings.

Ergonomically designed for ease in handling, this meter will float if inadvertently dropped into water

Hanna HI 98121

HI 98121 Includes

  • Protective Cap
  • Electrode Removal Tool to Allow You to Replace the Electrode in Case It Fails,
  • Batteries Installed
  • Instruction Manual