Level Measuring Instruments

Capacitive Level Sensor

The Capacitive Level Sensor is a high-precision industrial instrument designed for continuous liquid level measurement in a wide range of applications, including chemical, petroleum, food, and pharmaceutical industries. Utilizing the principle of capacitance, the sensor detects changes in liquid level accurately, providing reliable real-time monitoring for both simple and complex liquid media.

This sensor is ideal for measuring water, oil, acids, alkalis, and other conductive or non-conductive liquids. Its robust design ensures long-term stability and corrosion resistance, making it suitable for harsh industrial environments. With flexible installation options—top-mount or side-mount—and customizable measurement range and output signals, it adapts easily to specific industrial requirements.

Key Benefits:

  • High Accuracy: Ensures precise liquid level readings with minimal error.

  • Versatile Compatibility: Works with a wide variety of liquids and interfaces.

  • Durable & Corrosion-Resistant: Long-lasting performance in harsh conditions.

  • Easy Installation: Flexible mounting options reduce installation time and costs.

  • Customizable: Range, output, and configuration can be tailored for each application.

The capacitive level sensor provides a cost-effective, low-maintenance solution for real-time level monitoring, improving operational efficiency and process safety across industries.

  Level Measuring Instruments Description  

Capacitive Level Sensor – Key Features

  • Continuous Level Measurement – Accurately monitors the level of almost all corrosive and non-corrosive liquids.

  • Wide Operating Temperature – Performs reliably in extreme conditions from -190°C to +200°C.

  • High Pressure Tolerance – Supports operating pressures from -0.1 MPa to 32 MPa.

  • Minimal Environmental Impact – Measurement remains stable despite variations in pressure, temperature, or humidity.

  • High Stability & Anti-Interference – Ensures reliable and precise readings even in electrically noisy environments.

  • Explosion-Proof Design – Certified for safe operation in hazardous environments.

  • Customizable Solutions – Range, electrode type, output signal, and process connections can be tailored to specific applications.

Industrial capacitive level meter with flange mounting, designed for continuous liquid level measurement in tanks and pressure vessels, suitable for chemical, petroleum, and water treatment industries.
This image shows a capacitive water level sensor, suitable for water level measurement, with a digital display and stainless steel housing.

Applications of Capacitive Liquid Level Sensor

The capacitive liquid level sensor is widely used in industrial and process control applications where accurate, continuous liquid level measurement is required. Its robust design and high precision make it suitable for a variety of challenging environments.

Typical Applications:

  1. Chemical Industry – Monitoring and controlling the level of corrosive acids, alkalis, and other chemical solutions in storage tanks and reactors.

  2. Petroleum & Oil Storage – Level measurement in oil tanks, fuel depots, and petrochemical processing units.

  3. Food & Beverage Industry – Accurate monitoring of liquids such as water, juice, milk, and other food-grade fluids.

  4. Pharmaceutical Industry – Ensures precise liquid level control in pharmaceutical production and storage tanks.

  5. Water & Wastewater Treatment – Monitoring water levels in reservoirs, treatment tanks, and pipelines.

  6. Energy & Power Plants – Tank level measurement for fuel, cooling water, or other industrial fluids.

  7. Non-Metallic or Specialty Tanks – Works effectively in plastic, fiberglass, or other non-metallic containers with dual electrode configurations.

Advantages in Applications:

  • Provides continuous and high-precision level monitoring.

  • Operates reliably under extreme temperatures and pressures.

  • Corrosion-resistant and suitable for harsh chemical environments.

  • Compatible with automation and process control systems for real-time monitoring.

Capacitive Level Gauge – Measuring Principle

A capacitive level gauge is an instrument designed to measure the height of a liquid and convert it into an electrical signal for display, monitoring, recording, or process control.

The device typically consists of a single probe that acts as an immersed electrode inside the tank. This probe forms a capacitor with an opposing electrode, which is often the tank wall. The liquid inside the tank serves as the dielectric medium, affecting the capacitance between the two electrodes.

As the liquid level rises or falls, the capacitance changes proportionally. This variation is measured by applying an alternating voltage to the electrodes, usually at a radio frequency (RF). The measured capacitance is then converted into an electrical signal that accurately represents the liquid level, allowing precise and reliable level monitoring in a wide range of industrial applications.

This image shows a capacitive liquid level meter, featuring terminal blocks, a 24VDC power supply connection, and a precision sensor for liquid level measurement.
Capacitive level meter installation diagram showing continuous liquid level measurement inside a storage tank.

Capacitance Level Meter-Structure

A typical capacitive level sensor consists of the following main components:

  1. Electrode Probe

    • The primary sensing element, immersed in the liquid.

    • Can be rigid or flexible, made of steel or PTFE-coated material.

    • Forms a capacitor with the opposing electrode (often the tank wall).

  2. Opposing Electrode / Reference Electrode

    • Usually the tank wall for metallic tanks or a secondary electrode for non-metallic tanks.

    • Works together with the probe to create the capacitance that varies with liquid level.

  3. Electronics Housing / Signal Converter

    • Converts changes in capacitance into an electrical signal (typically 4–20 mA or voltage output).

    • Contains signal processing circuits, RF excitation, and sometimes explosion-proof protection.

  4. Process Connection

    • Flanges, threaded connections, or customized mounting options.

    • Ensures secure installation in the tank while maintaining proper sensor alignment.

  5. Electrical Connection

    • Standard M20×1.5 female thread or customized cable entries.

    • Provides connection to monitoring, display, or control systems.

  6. Protective Coating / Housing

    • PTFE or other corrosion-resistant materials for electrodes and housing.

    • Ensures durability in harsh or corrosive environments.

Optional Components:

  • Display module for local level reading.

  • Explosion-proof enclosure for hazardous areas.

  • Remote signal transmission module for long-distance monitoring.

  Level Measuring Instruments Parameter  

ParameterSpecification
Electrode TypeSingle electrode (metallic tanks); Double electrode (non-metallic tanks)
Electrode Material / Style1. Steel, rigid2. Steel, flexible3. PTFE-coated, rigid4. PTFE-coated, flexible
Measuring RangeRigid electrode: 0~3m (customizable)Flexible electrode: 0~60m (customizable)
Accuracy Class0.5, 1.0, 1.5, 2.0
Transmission Distance>1000m
Signal Output2-wire 4–20 mA DC
Load Resistance0–600 Ω
Pressure Rating6, 10, 25, 64, up to 320 bar
Operating Temperature-190 ~ 200 °C
Ambient Temperature-50 ~ +80 °C
Relative Humidity≤85%
Maximum Particle Size≤2 mm
Process Connection1. Flange: DN20–DN1502. Thread: M27×23. Customizable options
Electrical ConnectionM20×1.5 female thread
Explosion ProofEx d IIC T6 Gb

  Level Measuring Instruments OEM/ODM

Capacitive Level Sensors-OEM ODM

We provide comprehensive OEM and ODM services for capacitive liquid level sensors, catering to diverse industrial requirements and unique application needs.

Our OEM/ODM Capabilities Include:

  1. Custom Design & Engineering – Tailor the sensor’s measuring range, electrode type, material, and output signal to meet specific process requirements.

  2. Housing & Connection Customization – Offer various process connections, electrical interfaces, and explosion-proof enclosures.

  3. Branding & Labeling – Support custom logos, packaging, and documentation for your brand.

  4. Special Requirements – Adapt sensors for extreme temperatures, high pressure, corrosive media, or non-standard tank configurations.

  5. Flexible Production – Small-batch prototypes or large-scale industrial production, ensuring consistent quality and timely delivery.

Benefits for Customers:

  • Accelerates integration into your industrial systems.

  • Reduces development time and production costs.

  • Ensures reliable performance tailored to your specific application.

  • Provides full technical support from concept to delivery.

With our OEM/ODM solutions, your capacitive liquid level sensors can be fully customized to enhance operational efficiency, safety, and process control in your industry.

Industrial instrument manufacturer production workshop showing large-scale manufacturing of level gauges and process instruments

  Related Product Recommendations  

A capacitive level sensor forms a capacitor between its probe and an opposing electrode, with the liquid acting as the dielectric. Changes in liquid height alter the capacitance, which is converted into an electrical signal (typically 4–20 mA or voltage output).

Accuracy depends on:

Sensor TypeMeasuring RangeTypical AccuracyNotes
Rigid Electrode0–3 m±1% FSShort-range, high-stability
Flexible Electrode0–60 m±1.5% FSSuitable for deep tanks or irregular shapes

Capacitive sensors can detect level changes as small as 1–2 mm in optimal conditions. Accuracy is influenced minimally by pressure, temperature, and humidity due to the dielectric-based principle.

Yes. Sensors can be equipped with PTFE or other corrosion-resistant coatings. They are compatible with strong acids, alkalis, and aggressive chemical media.

Considerations for multi-phase liquids:

  • For stratified liquids (e.g., oil-water), the sensor may detect interface layers if configured with multiple electrodes.

  • Dielectric constants of the media affect capacitance; calibration may be needed for accurate measurements.

Example:

MediumDielectric Constant (εr)Recommendation
Water80Standard calibration
Oil2–4Use flexible PTFE-coated probe
Acid (HCl)25PTFE or corrosion-resistant electrodes
  • Metal Tanks: Single-electrode probe works, tank wall acts as opposing electrode.

  • Non-metallic Tanks (Plastic, Fiberglass): Dual-electrode setup needed.

  • Complex Shapes / Large Tanks: Flexible electrodes or multiple probes improve measurement coverage.

Insight: Using multiple probes in large tanks allows redundancy and reduces the effect of liquid turbulence or sloshing on accuracy.

Capacitive sensors are largely immune to environmental influences:

FactorEffect on MeasurementMitigation / Notes
PressureNegligible, up to 32 MPaEnsure electrode and sealing materials rated for tank pressure
TemperatureMinimal within -190 ~ 200°CUse PTFE or high-temperature materials for extreme conditions
HumidityNoneElectronics are sealed in IP65/IP67 housing
Viscosity / ParticlesMinor signal dampingUse flexible probes for slurries or max particle size ≤2 mm

Insight: Compared to ultrasonic or radar level sensors, capacitive sensors are less affected by foam, vapor, or condensate layers.

We offer extensive customization to match specific industrial needs:

Customizable FeatureOptions / Range
Electrode TypeRigid / Flexible, Steel / PTFE-coated
Measuring Range0–3 m (rigid), 0–60 m (flexible)
Signal Output4–20 mA, 0–10 V, RS485
Process ConnectionFlange DN20–DN150, M27×2, custom designs
Explosion ProtectionEx d IIC T6 Gb, custom certifications
Operating EnvironmentTemperature, pressure, chemical resistance tailored

Insight: Proper customization ensures long-term reliability, reduces maintenance, and optimizes ROI by matching the sensor to the specific liquid and tank conditions.

Yes. The output signal (typically 4–20 mA or RS485) allows seamless integration with PLCs, SCADA, DCS, or other monitoring systems.

Example Integration:

Signal TypeCompatible SystemNotes
4–20 mAPLC, DCSMost common; easy wiring, analog signal
RS485 ModbusSCADA, Industrial PCsSupports remote monitoring, multi-sensor networks
Voltage (0–10 V)Data loggers, Display PanelsShort-range applications, low-power systems

Insight: Capacitive sensors can provide real-time alerts, automated level control, and remote diagnostics. Compared to float or ultrasonic sensors, they offer higher reliability in extreme environments and corrosive media.

Why Choose Instrava

By choosing Instrava, you gain a partner with a deep understanding of industrial applications and the expertise to meet today’s operational challenges.
Our role extends beyond products—we support your success through dependable solutions and long-term commitment.

Engineering-Driven Innovation

Innovation at Instrava is guided by real industrial requirements. We continuously refine our technologies to address evolving operational challenges, ensuring practical and reliable performance in demanding environments.

Application-Specific Customization

We provide engineering-level customization to match specific process conditions. From measurement range and materials to output signals and installation options, our solutions are configured to fit real applications.

Proven Quality and Reliability

Quality and reliability are fundamental to every Instrava product. Manufactured under strict quality control and thoroughly tested, our instruments deliver accurate, stable, and long-term performance.

Global Capability with Local Support

Instrava combines global engineering expertise with responsive local support, ensuring our partners benefit from internationally aligned technology and timely regional service.

Comprehensive Product Portfolio

Our broad portfolio of measurement and control instruments enables us to address a wide range of industrial needs, providing integrated solutions from a single, reliable source.

Partner-Oriented Engineering Support

We work closely with our partners from technical consultation to after-sales support. Our focus is on delivering solutions that create lasting value and support long-term operational success.