What is Water Conductivity? EC Meters for Measuring Water Conductivity

Water is an extremely valuable resource, playing a crucial role in the lives of humans and other organisms. To ensure water quality for various uses, water quality assessment is essential.

One of the important indicators in assessing water quality is electrical conductivity (EC). In this article, we will explore the electrical conductivity of water and the best EC meters available today.

What is Electrical Conductivity (EC) of Water?

Electrical conductivity (EC) of water is a measure used to express the concentration of dissolved ions in a solution. The electrical conductivity of water refers to its ability to conduct electricity, heat, or sound.

The presence of ions in water is what causes its electrical conductivity. These ions are primarily metal salts such as KCl, NaCl, SO2-4, PO-4, NO-3. The higher the concentration of these ions, the higher the electrical conductivity of the water.

Electrical conductivity of water increases with temperature. As the temperature of the water rises, its conductivity also increases, and vice versa.

The EC of water is directly and closely related to the total dissolved solids (TDS) in the water. When salts dissolve in water, they form negatively charged (anions) or positively charged (cations) ions, affecting the water’s conductivity.

Độ dẫn điện của nước là gì?

Electrical Conductivity (EC) of Water and Unit Conversion

Unit of Electrical Conductivity:

The unit of electrical conductivity (EC) is siemens per centimeter (S/cm). However, a value of 1 S/cm is quite high in practice, so most EC measurements of solutions are expressed in units of millisiemens per centimeter (mS/cm) or microsiemens per centimeter (μS/cm).

  • mS/cm: This is equivalent to one-thousandth (1/1000) of S/cm.
  • μS/cm: This is equivalent to one-millionth (1/1000000) of S/cm.

EC Unit Conversion:

  • 1 mS/m = 10 µS/cm
  • 1 dS/m = 1000 µS/cm
  • mS/cm to dS/m = 1 or 1 dS/m = 1 mS/cm
  • 1 µmho/cm = 1 µS/cm


  • 1 S = 1 Siemens = 1 ohm^-1 = 1 mho.
  • The program uses µS/cm as the default unit for EC.

Electrical Conductivity (EC) of Water According to Standards

Water Type Electrical Conductivity (µS/cm)
   Pure Water 0.055
   Filtered Water 0.5
   Rainwater 5 – 30
   Potable Water 500 – 1000
   Groundwater 30-2000
   Industrial Wastewater ≥ 5000
   Seawater 54 000
   Concentrated Acidic and Basic Solutions Up to 1 000 000

Factors Affecting the EC Index in Water

The EC (electrical conductivity) index in water is an important parameter for evaluating water quality. A higher EC index indicates more contamination, which can be harmful to human health and aquatic life. Factors affecting the EC index in water include:

  • Concentration and Number of Charges: The electrical conductivity of water is directly proportional to the concentration of charges in the water. The higher the concentration of ions in the water, the greater the conductivity.
  • Mobility of Ions: The higher the mobility of the ions, the greater the conductivity.
  • Oxidation-Reduction State of Water: Water with a higher oxidation state has greater conductivity.
  • Concentration of Dissolved Salts: Conductivity is also proportional to the TDS (Total Dissolved Solids) index, which represents the total amount of dissolved solids in the water.

Additionally, the temperature of the water affects the EC index. The higher the temperature, the greater the conductivity.

chỉ số EC trong nước

Why is it Necessary to Test Water Conductivity?

There are several reasons to test the electrical conductivity (EC) of water, including:

  • Determining Total Dissolved Solids (TDS): This measurement, also known as mineralization, helps control the hardness and turbidity of water.
  • Monitoring Rapid Changes: Measuring conductivity allows us to detect quick changes in water quality.
  • Estimating Sample Size for Chemical Analyses: Knowing the conductivity helps estimate the sample size required for various chemical tests.
  • Determining Reagent and Chemical Amounts: Conductivity measurements help determine the amount of reagents and chemicals needed for water treatment.

Top 3 Best EC Meters for Water Conductivity

You can use EC meters and water testers to check the EC index in water. Here are the top 3 best EC meters available today:

YSI Pro30 Conductivity and Salinity Meter

The YSI Pro30 is a field device for measuring conductivity, salinity, pressure, TDS (Total Dissolved Solids), temperature, and other parameters. It is used in environmental, geological, food industry, and medical applications.

The YSI Pro30 can measure conductivity from 0 to 200 mS/cm, salinity from 0 to 70 ppt, conductance from 0 to 2000 μS/cm, TDS from 0 to 200 g/L, and temperature from -5 to 55°C. Additionally, the device can measure other parameters such as pH, dissolved oxygen, ORP (Oxidation Reduction Potential), and CO2 gas.

Designed for field use, the YSI Pro30 is compact and easy to carry and operate. It features a large, easy-to-read display, user-friendly control buttons, and can store up to 100 data sets.

Thiết bị đo độ mặn và độ dẫn YSI Pro30

Salinity, Conductivity, pH, and ORP Meter – YSI Pro1030

The YSI Pro1030 handheld meter for salinity, conductivity, pH, and ORP measurement is an upgraded version of its predecessor, the YSI 63. It features many new capabilities, particularly its robust performance even under the harshest conditions. The YSI Pro1030 meets the rigorous demands of field monitoring, allowing for quick and accurate measurement of pH or ORP, along with temperature, conductivity, specific conductance, salinity, and total dissolved solids (TDS).

This device is chosen for a wide range of water quality monitoring applications, offering the most cost-effective solution.

The outstanding features of the Pro1030 reduce the total cost of ownership throughout the product’s lifecycle, proving it to be smarter, more durable, and more versatile.

Thiết bị đo pH/độ dẫn/độ mặn/TDS/ ORP/nhiệt độ hiện trường Pro1030 hãng YSI

YSI Pro2030 Salinity, Dissolved Oxygen, Conductivity, and Temperature Meter

The Pro2030 is a handheld device for measuring dissolved oxygen (DO), conductivity, salinity, and TDS, with automatic compensation for changes in salinity. It is designed to be simple, robust, and highly accurate.

The parameters it can measure include dissolved oxygen (DO), salinity, conductivity, total dissolved solids (TDS), pressure, and temperature.

Users can replace the probes and cables to meet various measurement requirements.

Thiết bị đo đa chỉ tiêu, DO, độ mặn,TDS Pro2030 YSI

Conductivity, Temperature, and Pressure Logger – SeaGuard CTD

The SeaGuard CTD is a device for measuring multiple environmental parameters in both marine and freshwater settings. It is designed for continuous operation, recording salinity (via conductivity measurement), temperature, and depth (via pressure measurement) over long-term deployments.

Typical application areas include coastal circulation, climate research, and aquaculture. The SeaGuard CTD can also serve as a multiparameter platform for additional measurements.

Thiết bị đo ghi độ dẫn, nhiệt độ, áp suất - Seaguard CTD

YSI ProDss Multiparameter Water Quality Meter

The ProDSS (digital sampling system) multiparameter meter is an intelligent device that allows for rapid measurement of multiple water quality parameters simultaneously, both in the field and in the laboratory. It is utilized in various fields such as surface water monitoring, groundwater analysis, coastal/estuarine water assessment, and aquaculture.

The device is designed with 4 digital sensor ports, enabling accurate measurement of numerous fundamental parameters such as dissolved oxygen (DO), turbidity, conductivity, specific conductance, salinity, resistivity, total dissolved solids (TDS), pH, ORP, combined pH/ORP, ammonia, nitrate, chloride, temperature, and more, at various depths for reliable results. Users can select sensors according to their specific needs.

The instrument operates reliably in marine and tropical climate environments.


Máy đo đa thông số chất lượng nước YSI ProDss

EC30A Conductivity (EC), Temperature, TDS Pen

The EC30A Temperature, Conductivity, TDS Pen is designed to be compact, convenient, and user-friendly. It is specifically crafted for water quality measurement and monitoring tasks in surface water, groundwater, as well as for assessing domestic water quality and aquaculture environments.

Featuring an intuitive graphical interface, simple operation, and easy calibration, users can effortlessly replace the electrodes, ensuring the device is always ready for use. The EC30A Pen provides quick and accurate measurements of Conductivity, Temperature, and Total Dissolved Solids (TDS).

Key Features:

  • Easy temperature unit conversion: °C and °F
  • Replaceable electrodes reduce maintenance and repair costs in case of damage.
  • Automatic shut-off function when not in use.
  • Measurement results displayed directly on the LCD screen.
  • Data hold function to retain measurement values on the screen.
  • Long battery life with low battery indication, allowing users to manage the device’s operation time proactively.

Bút đo độ dẫn (EC), nhiệt độ, TDS - EC30A

If you need advice on purchasing an EC conductivity meter but haven’t selected the appropriate one yet, please contact Reeco Tech for guidance on the most suitable type of meter.


Other news

Operating the meteorological and marine weather monitoring system and lightning warning system at Tan Thuan Wind Power Plant


Contents of the hydro-meteorological database


How is not installing water resource monitoring and supervision equipment penalized?


Regulations on meteorological monitoring stations in national parks


What is algae? How to detect and control green algae in aquaculture?

error: Content is protected !!