Hanna Instrument Direct Soil Measurement pH Portable Meter – HI99121
The HI99121 portable pH meter is ideal for soil testing. Users can test the pH of soil directly or after preparing a soil slurry with deionized water using the HI99121 and HI12923 direct soil pre-amplified pH and temperature probes.
The HI12923 has a conical, rugged tip that can be inserted directly into wet or soft soil. The kit includes a plastic auger to perforate the ground in harder soils.
- Automatic Temperature Adjustment
- Calibration of Two Points Automatically
Turn cap to create positive head pressure allowing for more reference electrolyte to flow.
Built-In Temperature Sensor
Automatic compensation of temperature variations.
The fast, stable response that is immune to electrical noise due to humidity.
Soil can be acid, neutral, or alkaline, according to its pH value. Most plants prefer a pH range from 5.5 to 7.5, but some species prefer more acid or alkaline soils. Nevertheless, every plant requires a particular range of pH, for optimum growth.
pH strongly influences the availability of nutrients and the presence of microorganisms and plants in the soil. For example, fungi prefer acidic conditions whereas most bacteria, especially those supplying nutrients to the plants, have a preference for moderately acidic or slightly alkaline soils. In fact, in strongly acidic conditions, nitrogen-fixing and the mineralization of vegetable residual are reduced. Plants absorb the nutrients dissolved in the soil water and the nutrient solubility depends largely on the pH value. Hence, the availability of elements is different at different pH levels.
Each plant needs elements in different quantities and this is the reason why each plant requires a particular range of pH to optimize its growth. For example, iron, copper, and manganese are not soluble in an alkaline environment. This means that plants needing these elements should theoretically be in an acidic type of soil. Nitrogen, phosphorus, potassium, and sulfur, on the other hand, are readily available in a pH range close to neutrality. Furthermore, abnormal pH values, increase the concentration of toxic elements in plants. For example, in acid conditions, there can be an excess of aluminum ions in such quantities that the plant cannot tolerate. Negative effects on chemical and physical structure are also present when pH values are too far from neutral conditions (break up of aggregates, a less permeable and more compact soil).
The HI99121 meter features a large multi-level LCD screen that displays both pH and temperature readings simultaneously with 0.01 pH resolution and accuracy of ±0.02 pH. The LCD screen also has indicators for calibration status and stability, as well as on-screen tutorial messages. The HI99121 has many advanced features that are found in more expensive portable instrumentation including automatic calibration, buffer recognition, and temperature compensation. The battery percent level is displayed at start up alerting the user to the remaining battery power that is available. The supplied HI12923 is a glass body, amplified pH electrode with a built-in temperature sensor designed specifically for measuring the pH in soils.
- Automatic Temperature Compensation
- One or two-point automatic calibration
- BEPS – Alerts the user of low battery power that could adversely affect readings
- Compact, heavy-duty, and waterproof
- Battery % displayed on start-up
- HELP feature displays messages on the LCD
For high accuracy and to ensure the soil is wet use the HI7051M soil preparation solution.
|Product Name||Direct Soil Measurement pH Portable Meter – HI99121|
|pH Range||-2.00 to 16.00 pH; -2.0 to 16.0 pH|
|pH Resolution||0.01 pH; 0.1 pH|
|pH Accuracy||±0.02 pH; ±0.1 pH|
|pH Calibration||automatic, at one or two points with two sets of standard buffers (pH 4.01 / 7.01 / 10.01 or pH 4.01 / 6.86 / 9.18)|
|pH Temperature Compensation||automatic ‐5.0 to 105.0 °C/23.0 to 221.0 °F|
|pH CAL Check (electrode diagnostics)||probe condition indicator|
|mV Range||±825 mV (pH‐mV)|
|mV Resolution||1 mV|
|mV Accuracy||±1 mV (pH‐mV)|
|Temperature Range||-5.0 to 105.0°C / 23.0 to 221.0°F|
|Temperature Resolution||0.1°C / 0.1°F|
|Temperature Accuracy||±0.5°C (up to 60°C); ±1.0°C (outside) / ±1°F (up to 140°F); ±2.0°F (outside)|
|pH Electrode||HI12923 glass body, pre-amplified pH electrode for soil measurement with internal temperature sensor, quick connect DIN connector and 1 m (3.3’) cable (included)|
|Automatic Shut-Off||user selectable|
|Battery Type/Life||1.5V (3) AAA / approximately 1400 hours of continuous use; auto-off after 8 minutes of non-use|
|Environment||0 to 50°C (32 to 122°F); RH max 100%|
|Dimensions||154 x 63 x 30 mm (6.1 x 2.5 x 1.2”)|
|Weight||196 g (6.91 oz.)|
|Ordering Information||HI99121 is supplied with HI12923 pH electrode, HI721319 soil auger, HI7051M soil preparation solution (230 mL), HI70004 pH 4.01 buffer solution sachet (20 mL), HI70007 pH 7.01 buffer solution sachet (20 mL), HI700663 cleaning solution sachet for inorganic soil deposits (20 mL), HI700664 cleaning solution sachet for organic soil deposits (20 mL), 100 mL plastic beaker, batteries, instructions, and a hard carrying case.|