Conductivity (EC)
What is Conductivity?
Conductivity is an expression of the ability of a solution to conduct electric current. It is expressed as a microsiemen (micro-Siemens per centimeter or µS/cm) or in higher conductivity levels as a millisiemen. It is also the reciprocal of resistivity.
Some industries such as water treatment have adopted a measurement expressed as TDS (Total Dissolved Solids). TDS is approximated with conductivity using a multiple factor and is expressed in parts per million (ppm).
Contacting Conductivity Sensors
Contacting conductivity sensors measure conductivity with two surfaces in contact with the sample. These surfaces can be constructed of graphite, stainless steel, platinum, or similar materials. An AC voltage waveform is sent through one contact of the sensor and passes through the liquid being measured. The second contact surface receives the signal. The resulting measurement determines the conductivity of the water and is displayed on a conductivity instrument which expresses the measurement as microsiemens, millisiemens, or total dissolved solids (ppm).
Toroidal (Inductive) Conductivity Sensors
Toroidal conductivity sensors consist of an inductive 2-coil system encapsulated in an inert plastic case. The sending coil generates a magnetic field, which in turn produces an electric current in the liquid being measured. The strength of the current, which is picked up as a magnetic field by the receiving coil, is proportional to the concentration of ions in solution. This inductive system can eliminate the polarizing effects that may produce erratic measurements with a contacting conductivity sensor. Toroidal sensors are also resistant to fouling, because the coils are not in contact with the process. Therefore, toroidal conductivity sensors have become the standard in many high conductivity applications, such as chemical processing, cooling towers, and seawater monitoring.
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Custom Conductivity / TDS Sensor Design & Manufacturing
Designing a new water treatment product? We can help. Sensorex specializes in the design and manufacture of custom water analysis sensors for our OEM partners. Collaborate with our expert team of engineers and chemists to design a conductivity sensor that meets the needs of your system. Body size and shape, materials of construction, measurement range, cable length, connector type and other features can be adjusted to fit your application requirements.
Conductivity
Our extensive line of conductivity and TDS products provide options for almost any application.
Popular ProductsSensorex Conductivity Best Sellers
CS150 – Graphite Contacting Conductivity Sensor, 12 mm
Used for Laboratory and Light Industrial Applications: Cells are made from graphite to provide good performance for the value. Choose…
TDS / Conductivity Calibration Standards
TDS/Conductivity instruments and sensors must be calibrated together. For a single-point calibration, select the one solution that approximates the expected…
CS200 – Contacting Conductivity Sensor, 12 mm Platinum
The CS200 12 mm Platinum Contacting Sensor is ideally suited for laboratory or light industrial process applications. It can be…
CS650 – Conductivity Sensor, Stainless Steel
The Sensorex CS650 Stainless Steel Conductivity Sensor is a general purpose sensor to be used in a variety of benign…
CX105 – Conductivity Transmitter, Loop-Powered 4-20mA
Our CX105 conductivity transmitter is an isolated output 4-20mA industrial transmitter for reading contacting conductivity sensors. The CX105 transmitter also…
EM802-EC – Smart Conductivity Modules (4-20mA or MODBUS/RS485) for S8000 Series
The EM802-EC is our most cost-effective solution for connecting our S8000 series Contacting Conductivity sensors to a PLC or SCADA…
ITCS3020 – Smart General Purpose Noryl Toroidal Conductivity Sensor
Sensorex's ITCS3020 Smart General Purpose Noryl Toroidal Conductivity Sensor communicates directly via 4-20mA or Modbus output. Configuration and calibration done…
TCSMA – Conductivity Transmitter, Toroidal
Our TCSMA online toroidal conductivity transmitter without display is built for water treatment monitoring and aggressive process chemical applications. Ideally…
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