Combo meter for liquid analysis – Hanna Instruments HI98130 pH/EC/TDS meter
The Hanna Instruments HI98130 is a portable combination meter to measure pH, electrical conductivity (EC), total dissolved solids (TDS) and temperature of liquids. With the four measurement functions combined in one handheld instrument, users can assess several aspects of liquid quality without switching between separate meters. It is a useful tool for routine measurements in hydroponics, aquariums, swimming pools, ponds and other applications where it is important to monitor water conditions.
The HI98130 measures pH from 0.00 to 14.00 pH and expanded electrical conductivity from 0.00 to 20.00 mS/cm. Its TDS measurement range is up to 10.00 ppt, making it suitable for testing liquids with higher concentrations of dissolved solids than the comparable HI98129 model. The meter has a temperature measurement function as well, that can be used to interpret results under different measurement conditions.
How the HI98130 pH, EC, TDS and temperature meter functions
The measurements vary for each liquid tested.
- pH: A measure of how acidic or alkaline a liquid is, on a scale of 0 to 14. Values under 7 indicate acidic conditions, 7 is neutral, and values above 7 indicate alkaline conditions.
- Electrical conductivity (EC): Indicates the ability of a liquid to easily conduct electricity. Conductivity is caused by dissolved ions, such as mineral salts and nutrients. EC is frequently used to monitor nutrient solutions in hydroponic systems.
- Total Dissolved Solids (TDS): Gives an estimate of the amount of dissolved substances in a liquid. The HI98130 uses a selectable conversion factor to convert the conductivity reading to a TDS value.
- Temperature: Measures sample temperature and provides temperature compensation for pH and EC/TDS readings.
The instrument measures pH with a pH-sensitive electrode and EC with a graphite conductivity electrode. It has a built-in temperature sensor that gives you temperature readings. Automatic temperature compensation (ATC) compensates for temperature variations in pH and conductivity measurements, allowing users to compare readings taken under different conditions.
Key features and practical advantages
- 4 measurements in 1 device: Measure pH, EC, TDS and temperature with only 1 handheld instrument.
- Wide EC measurement range: Suitable for liquids with relatively high conductivity; the conductivity can be measured up to 20.00 mS/cm.
- Replaceable pH electrode: The HI73127 pH electrode can be replaced when necessary, instead of having to replace the whole meter.
- Graphite conductivity electrode: The graphite electrode is designed to be resistant to fouling by salts and other materials.
- Automatic calibration: The meter is equipped with the function of Automatic pH Calibration and single point EC/TDS calibration with help of suitable reference solutions.
- Adjustable TDS conversion factor: Set the conversion factor from 0.45 to 1.00 to suit the measurement needs.
- Automatic temperature compensation: Helps correct temperature-related measurement variations.
- Two level LCD display: Measurement information displayed in an easy to read format.
- Automatic shut-off: Shuts the meter off after eight minutes without activity to help save battery power.
- Waterproof floating housing: If the camera falls into a tank by accident, it will float and thus be easier to retrieve.
Performance specifications
The following specifications are applicable to the Hanna Instruments HI98130.
- Manufacturer: Hanna Instruments
- Model: HI98130
- Type: pH/EC/TDS/temperature Meter Combo
- pH measuring range: 0.00–14.00 pH
- pH resolution: 0.01 pH
- pH accuracy at 20 °C: ± 0.05 pH
- EC measuring range: 0.00–20.00 mS/cm
- EC resolution: 0.01 mS/cm
- TDS measurement range: 0.00–10.00 ppm
- TDS resolution: 0.01 parts per thousand
- Accuracy of EC/TDS at 20 °C: ±2% of full scale
- Temperature range: 0.0 to 60.0 °C
- Temperature resolution: 0.1 °C
- Temperature accuracy at 20 °C: ±0.5 °C
- Replaceable pH electrode: HI73127
- TDS conversion factor: Variable between 0.45 and 1.00
- Temperature compensation: Automatic, adjustable EC/TDS temperature coefficient
- Calibration: Automatic pH Calibration; Single Point EC/TDS Calibration
- Power supply: 4 × 1.5 V batteries
- Battery life: Estimated 100 hours of continuous use ???
- Automatic shut-off: 8 minutes of inactivity
- Operating environment: 0–50 °C, maximum 100% relative humidity
- Dimensions: 163 × 40 × 26 mm
- Weight: 100 g
Specifications are based on information and instructions supplied by the manufacturer.
Suitable applications and compatibility
The HI98130 can be used in situations where pH, conductivity, dissolved-solids estimates and temperature are important to liquid analysis.
- Hydroponics: Measure nutrient solution pH and conductivity to assist in evaluating growing conditions and nutrient concentration.
- Aquariums: Monitor water pH and conductivity as part of routine water quality monitoring.
- Swimming pools: Useful for regular water testing to monitor pH and conductivity. The meter does not measure the concentration of chlorine directly.
- Ponds and water tanks: Observe water measurements over time and look for changes in pH or conductivity.
- General water tests: Test liquid samples in school, garden and other routine testing environments.
The HI98130 is particularly suited for applications with high conductivity measurements. The similar HI98129 has an EC range of 0–3999 µS/cm and a TDS range of 0–2000 ppm. The HI98130 measures EC instead up to 20,00 mS/cm and TDS up to 10,00 ppt. Thus the choice between the two models is partly determined by the expected conductivity and concentration of dissolved solids in the samples.
Calibration, operations and maintenance
Before measuring a sample, check that the electrode is clean and that the meter has been calibrated with appropriate reference solutions. The instrument is equipped with standard buffer sets for pH calibration, such as pH 4.01, 7.01, and 10.01, or pH 4.01, 6.86, and 9.18. The HI98130 is factory calibrated for EC/TDS with the manufacturer’s recommended high range standard.
Place the sensing section in the sample as shown in the instruction manual when measuring and allow the reading to stabilize before recording. Rinse electrode between samples to avoid cross-contamination. After use, rinse the pH electrode and store it in the recommended solutions as specified by the manufacturer.
The pH electrode is a consumable item and may need replacing if it becomes damaged, contaminated or is unable to hold a reliable calibration. The HI73128 tool is provided to help remove the electrode.
Important considerations prior to use
The HI98130 is a measuring instrument, not a treatment device. It doesn’t automatically alter pH, add nutrients or remove dissolved substances from a liquid. TDS readings are derived from conductivity. They are not individual measurements of every dissolved substance. Thus, the reported TDS value can depend on the choice of conversion factor.
The housing is designed to be water-resistant and to float if dropped into a tank, but users should follow the manufacturer's handling instructions and avoid exposing the instrument to conditions outside its specified operating range. Consistent results require regular calibration, proper storage of the electrode and correct handling of samples.
