Product Description: Portable pH/EC/TDS/Temperature Meter – HI9811-51

The Hanna HI9811-51 Portable pH/EC/TDS/Temperature Meter is a versatile multiparameter water quality testing instrument designed to measure pH, electrical conductivity (EC), total dissolved solids (TDS), and temperature using a single multiparameter probe. It is a practical solution for agriculture, greenhouse, hydroponics, water testing, laboratory analysis, and general water quality monitoring.

The HI9811-51 combines four essential water quality measurements in one compact portable instrument. Its supplied HI1285-51 probe incorporates pH, EC/TDS, and temperature sensors in a single polypropylene probe body, eliminating the need to change probes when switching between measurement parameters.

The meter features a large LCD that displays the selected measurement together with on-screen tutorial messages. Dedicated keys allow users to select Portable pH/EC/TDS/Temperature Meter – HI9811-51 measurement modes, while manual calibration controls provide straightforward one-point calibration for pH and EC/TDS.

Specifications of Hanna HI9811-51 Portable pH/EC/TDS/Temperature Meter

• Product Name: Portable pH/EC/TDS/Temperature Meter
• Model: HI9811-51
• Product Type: Portable Multiparameter Meter
• Parameters: pH / EC / TDS / Temperature
• pH Range: 0.0 to 14.0 pH
• pH Resolution: 0.1 pH
• pH Accuracy: ±0.1 pH
• EC Range: 0 to 6000 µS/cm
• EC Resolution: 10 µS/cm
• EC Accuracy: ±2% F.S.
• TDS Range: 0 to 3000 ppm (mg/L)
• TDS Resolution: 10 ppm (mg/L)
• TDS Accuracy: ±2% F.S.
• Temperature Range: 0.0 to 70.0°C
• Temperature Resolution: 0.1°C
• Temperature Accuracy: ±0.5°C
• TDS Conversion Factor: 0.5
• pH Calibration: Manual, 1-point
• EC/TDS Calibration: Manual, 1-point
• EC/TDS Temperature Compensation: Automatic, 0 to 70°C
• Temperature Coefficient: β = 2%/°C
• Probe: HI1285-51 Multiparameter Probe
• Probe Body: Polypropylene
• Probe Connection: 8-pin DIN
• Probe Cable Length: 1 m
• Temperature Sensor: Built-in
• Battery: 1 × 9V Alkaline Battery
• Battery Life: Approximately 150 hours of continuous use
• Auto Shut-Off: After 8 minutes of non-use
• Operating Environment: 0 to 50°C
• Operating Humidity: Up to 100% RH
• Dimensions: 145 × 80 × 36 mm
• Weight: Approximately 230 g
• Brand: Hanna Instruments
• Origin: Romania

The specifications above follow Hanna’s official documentation. Some third-party listings show different temperature accuracy or battery-life figures, so the official Hanna documentation is used where specifications differ.

Hanna HI9811-51 for pH Measurement

The Hanna Portable pH/EC/TDS/Temperature Meter – HI9811-51 measures pH across a range of 0.0 to 14.0 pH, with a resolution of 0.1 pH and specified accuracy of ±0.1 pH.

The supplied HI1285-51 probe includes an amplified pH electrode designed to reduce interference from electrical noise generated by equipment such as motors, pumps, and ballasts. This makes the meter suitable for different water testing and agricultural environments.

The pH measurement system uses manual one-point calibration, allowing users to calibrate the meter using the dedicated calibration control.

EC Measurement with HI9811-51

The HI9811-51 measures electrical conductivity from 0 to 6000 µS/cm, with a resolution of 10 µS/cm and accuracy of ±2% full scale.

EC measurement is useful for monitoring the ionic conductivity of water and nutrient solutions. This makes the instrument particularly useful in hydroponics, greenhouse applications, agriculture, irrigation water testing, and general water quality monitoring.

The EC/TDS system uses manual one-point calibration through the dedicated slope adjustment control.

TDS Measurement

The Hanna HI9811-51 also measures Total Dissolved Solids (TDS) from 0 to 3000 ppm (mg/L) with a resolution of 10 ppm and accuracy of ±2% full scale.

The instrument uses a fixed 0.5 conversion factor for converting conductivity measurements to TDS. This allows users to monitor dissolved solids in water and nutrient solutions without requiring a separate TDS meter.

Temperature Measurement and Automatic Compensation

The HI9811-51 measures temperature from 0.0 to 70.0°C with a resolution of 0.1°C. The supplied HI1285-51 probe includes a built-in temperature sensor.

Temperature compensation is automatically applied to EC and TDS measurements from 0 to 70°C, using a temperature coefficient of β = 2%/°C. This helps compensate conductivity and TDS measurements for changes in sample temperature.

HI1285-51 Multiparameter Probe

The HI1285-51 is the multiparameter probe supplied with the HI9811-51. It combines pH, EC/TDS, and temperature sensors into one probe.

The probe has a polypropylene body, an amplified pH electrode, EC/TDS sensing elements, and an internal temperature sensor. It connects to the meter through an 8-pin DIN connector and includes a 1-meter cable.

Using a single multiparameter probe means users do not need to change probes when switching between pH, EC, TDS, and temperature measurements.

Large LCD Display and Easy Operation

The Hanna HI9811-51 features a large LCD that displays the selected measurement together with tutorial messages to guide users during operation.

Dedicated buttons allow users to select:

• pH measurement
• EC measurement
• TDS measurement
• Temperature measurement

The display also includes a battery-level indicator and on-screen instructions, making the meter straightforward to operate for routine water testing.

Portable and Compact Design

The HI9811-51 Portable pH/EC/TDS/Temperature Meter has dimensions of approximately 145 × 80 × 36 mm and weighs around 230 g.

Its compact handheld design makes it convenient for laboratory testing as well as field measurements. The meter operates on a 9V alkaline battery, and Hanna documentation specifies approximately 150 hours of continuous use with automatic shut-off after 8 minutes of inactivity.

Applications of Hanna HI9811-51

The Hanna Portable pH/EC/TDS/Temperature Meter – HI9811-51 can be used for a wide range of applications, including:

• Water quality testing
• Agricultural water testing
• Hydroponic nutrient solution testing
• Greenhouse applications
• Irrigation water testing
• Laboratory water analysis
• Environmental water monitoring
• Aquaculture applications
• Nutrient solution monitoring
• General-purpose pH measurement
• Electrical conductivity testing
• TDS measurement
• Temperature measurement
• Research and educational laboratories
• Field water testing
• Water treatment applications

Hanna specifically identifies the HI9811-51 as suitable for agriculture, greenhouse, and hydroponic applications.

Why Choose Hanna HI9811-51 Portable pH/EC/TDS/Temperature Meter?

• Measures pH, EC, TDS, and temperature
• One multiparameter probe for four measurements
• pH range of 0.0 to 14.0
• EC range up to 6000 µS/cm
• TDS range up to 3000 ppm
• Temperature range up to 70°C
• Automatic EC/TDS temperature compensation
• Built-in temperature sensor
• Large LCD with tutorial messages
• Manual one-point calibration
• Amplified pH electrode
• Polypropylene multiparameter probe
• 1-meter probe cable
• Compact and portable design
• 9V battery operation
• Suitable for agriculture and hydroponics
• Suitable for laboratory and water quality testing
• Model: HI9811-51
• Brand: Hanna Instruments
• Origin: Romania

Frequently Asked Questions (FAQ)

1. What is the Hanna HI9811-51?

The Hanna HI9811-51 is a portable multiparameter meter designed to measure pH, electrical conductivity (EC), total dissolved solids (TDS), and temperature using a single probe.

2. What is the pH range of HI9811-51?

The pH measurement range is 0.0 to 14.0 pH, with a resolution of 0.1 pH and accuracy of ±0.1 pH.

3. What is the EC range of Hanna HI9811-51?

The EC range is 0 to 6000 µS/cm, with a resolution of 10 µS/cm.

4. What is the TDS range of HI9811-51?

The TDS range is 0 to 3000 ppm (mg/L) with a resolution of 10 ppm.

5. What temperature range can HI9811-51 measure?

The temperature measurement range is 0.0 to 70.0°C, with a resolution of 0.1°C.

6. Does HI9811-51 have automatic temperature compensation?

Yes. EC and TDS measurements have automatic temperature compensation from 0 to 70°C, using a temperature coefficient of β = 2%/°C.

7. Which probe is supplied with the HI9811-51?

The meter is supplied with the Portable pH/EC/TDS/Temperature Meter – HI9811-51 multiparameter probe with a polypropylene body, internal temperature sensor, 8-pin DIN connector, and 1-meter cable.

8. What type of battery does the HI9811-51 use?

The meter uses one 9V alkaline battery. Hanna’s official documentation lists approximately 150 hours of continuous use.

9. Is the HI9811-51 suitable for hydroponics?

Yes. Hanna identifies the HI9811-51 as particularly suitable for agriculture, greenhouse, and hydroponic applications.

10. What are the dimensions of the HI9811-51?

The meter measures approximately 145 × 80 × 36 mm and weighs approximately 230 g.

11. What is the brand of HI9811-51?

The brand is Hanna Instruments.

12. What is the origin of Hanna HI9811-51?

The product is listed as Romania origin in the product information provided for this model.

Conclusion

The Hanna Portable pH/EC/TDS/Temperature Meter – HI9811-51 is a practical multiparameter instrument for measuring four important water-quality parameters with a single probe. It combines pH, electrical conductivity, total dissolved solids, and temperature measurement in a compact portable unit.

With a 0.0–14.0 pH range, 0–6000 µS/cm EC range, 0–3000 ppm TDS range, and 0.0–70.0°C temperature range, the HI9811-51 is suitable for agriculture, hydroponics, greenhouse operations, laboratory testing, water-quality monitoring, and other applications where multiple water parameters need to be checked with one instrument.