Conductivity Measurements for Clean-in-Place (CIP) System


In the food & beverage, pharmaceutical, and chemical industries, tanks and piping are cleaned and sterilized with various cleaning solutions, fresh or hot water, or steam after manufacturing products is completed. Clean-in-place (CIP) is the system designed for automatic cleaning and disinfecting in these processes. Recovery of cleaning solutions contributes significantly to the reduction of chemical and/or wastewater processing costs.

Process Overview

Common CIP processes first wash the tanks and piping with cleaning agents such as sodium hypochlorite, caustic soda, or nitric acid. Then the detergent is washed with freshwater; the detergent is collected at this time. When the detergent concentration of the washing solution reaches the reference value or less, the collection is stopped and the solution is released to the drain line.

Cleaning is carried out under certain conditions, in a precise order, and utilizes multiple detergents. If the wrong operation is performed, it cannot be detected externally; therefore, it is impossible to perform the specified washing and reduction losses which may occur due to operational errors.


The number of cleaning agents required could present a manufacturing cost challenge. The recovery of cleaning solutions significantly reduces chemical costs as well as wastewater processing costs. Therefore, accurate and reliable conductivity measurements are critical for clean-in-place (CIP) or water-for-injection (WFI) applications; inaccurate readings can cause runtime losses and an increase in material and energy usage.


Yokogawa’s FLEXA series analyzers can connect to either inductive or contacting conductivity sensors. Each type of sensor technology serves a specific purpose. An inductive conductivity sensor offers a wide measurement range and is well suited to use in dirty, corrosive, or highly conductive solutions. In those applications, it requires less maintenance than a contacting sensor. Contacting conductivity sensors are ideal for use in pure and ultrapure water applications. Their high sensitivity to ions present provides the highest accuracy for low conductivity measurements.

Yokogawa’s ISC40 inductive conductivity sensors have earned a favorable reputation in the recovery of cleaning solutions. Accurate conductivity measurement in CIP systems can reduce operating costs by up to 10%. 


Washing detergent with freshwater is time-sensitive. Introducing a conductivity meter makes it possible to prevent unnecessary cleaning. Since cleaning agents have high conductivity while freshwater (distilled water) has low conductivity, a conductivity measurement allows the operator to distinguish which liquid is flowing through the process piping. This enables optimization of the cleaning and sterilizing process, resulting in: 

  • Reduced operating costs
  • Improved precision in boundary surface measurement

Product Recommendations

Conductivity Measurement System: 
Process Liquid Analyzer:
2-wire FLXA202 Conductivity Analyzer
4-wire FLXA402 Conductivity Analyzer


Chemical Solution (High Concentration) Conductivity Sensor Selection:
Inductive Conductivity Sensor Selection: 
With the inductive conductivity, ISC40 series, one sensor can measure the full range of conductivity from 0-2000 mS/Cm. Steam sterilization capability is possible since the measurements can be performed at process solution temperatures of -10 to 130°C and pressures no greater than 2 MPa (20 kgf/cm2).

Option #1: 
ISC40G General Purpose Sensor
ISC40S Intrinsically Safe Sensor
Available in PEEK and PFA material for more aggressive chemicals

Holder Selection:
ISC40FS/ISC40FF Insertion of Flow-thru assembly
PR10 Retractable assembly

Freshwater (Distilled water) Sensor Selection:
Contacting Conductivity Sensor Selection: 
Analog and Digital SMART sensors are available. Analog options allow users to interface with a traditional system. SENCOM technology allows sensors to transmit and receive data when connected to a transmitter/analyzer or any PC. A SMART digital sensor maintains specific measurement and calibration data on an integrated chip that is integral to the sensor. This provides easy plug and play solutions. The data management software optimizes the performance of sensors for enhanced reliability and process safety.

Option #2: 
SC4A Conductivity Sensor (fittings available for insertion, sanitary, or retractable installations.)


  • Chemical

    Chemical plants rely on continuous and batch production processes, each posing different requirements for a control system. A continuous process calls for a robust and stable control system that will not fail and cause the shutdown of a production line, whereas the emphasis with a batch process is on having a control system that allows great flexibility in making adjustments to formulas, procedures, and the like. Both kinds of systems need to be managed in available quality history of product, and to be able to execute non-routine operations. With its extensive product portfolio, experienced systems engineers, and global sales and service network, Yokogawa has a solution for every plant process.

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  • Food & Beverage

    The food and beverage industry must produce safe, high-quality foods and beverages for consumers. In addition to quality control, the manufacturing processes include many challenges such as managing ingredients, improving efficiency and handling global environmental issues. Yokogawa leverages its decades of technological expertise to help customers build and operate the ideal factory.

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  • Pharmaceutical

    Under continual pressure to increase profitability, maintain government compliance, and meet emerging market opportunities, the pharmaceutical manufacturing industry faces unique challenges that require unique solutions. As one of the world’s leading industrial automation suppliers, Yokogawa is poised and prepared to deliver those solutions, creating individualized lean manufacturing techniques that deliver consistent, measurable results.

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  • Specialty & Fine Chemical

    Yokogawa has long served customers in the specialty and fine chemicals market. With a market leading batch solution that offers the best in class reliability and flexibility as well as industry experts who understand the complex requirements in designing a batch solution, you can be assured that in your partnership with Yokogawa you will have a system that will enable you to produce products that meet your customers’ needs in the future while maintaining safety and regulatory compliance.

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Related Products & Solutions

  • 2-Wire Transmitter/Analyzer FLXA21

    The FLEXA™ series analyzers are used for continuous on-line measurements in industrial installations. With an option for single or dual sensor measurement, they are the most flexible two-wire analyzer available.

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  • Conductivity Sensors

    • Conductivity sensors and electrodes
    • Process conductivity, resistivity, WIFI, demineralizer water, RO water, percent concentration, boiler blowdown, and TDS 
    • Retractable, flow thru, immersion, and direct insertion
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  • pH and ORP Analyzers

    pH and ORP meters, analyzers and transmitters are used for continuous process monitoring of pH and ORP to ensure water/product quality, monitor effluent discharge, batch neutralization, pulp stock, scrubbers, cooling towers, chemical, water/wastewater treatment and many other applications.

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Have Questions?

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