Capacitive Level Sensor

Capacitive Level Sensor uses the change in capacitance between the sensor probe and the material as the sensing principle and measures the changing level accordingly, providing continuous output to a measurement signal.

The electronics then process these signals and give a standard 4–20 mA output, which can easily be interfaced to a PLC or any other control system.

For corrosive liquids and chemicals, it works well when the sensors are PTFE-insulated.

It can be employed in case of powder or granule levels as well as tank storage.

• Measures level using capacitance sensing technology.
• Performance is unaffected by density, conductivity, viscosity, or corrosive nature of the liquid.
• Probe can be supplied in PTFE or SS316 and customized to the required length.
• Cable version available for measuring distances up to 10 meters.
• Suitable for powders, granules, liquids, and slurry applications.
• Reliable operation even during continuous material feeding.
• Dust-resistant sensing for accurate level measurement.
• Intrinsically safe design with flameproof enclosure option.

• Measuring Range: 0 to 10 m (Depending on Probe)
• Design Temperature: Up to 85°C
• Design Pressure: Up to 15 Kg/cm²
• Application: Liquids, Chemicals & Some Slurries

Measurement of Capacitance

In the Capacitive Level Sensor, a capacitance field is formed between the sensing probe and the wall of the tank or reference electrode. Both these components make a capacitor.

Level Measurement

If the tank is empty, then there will be only air in the region surrounding the probe. But when the liquid or bulk solids start coming in contact with the probe, then the electrical capacitance will change because of the difference in dielectric constant.

Signal Processing

There are no moving parts used in this sensor, and all the changes in capacitance are monitored and converted into a level measurement.

Output Signal Formation

The internal electronics will take the reading and convert it into the desired 4–20 mA output signal or some other type of output signal, as required.

Continuous Level Measurement

The level measurement of liquids, slurry, powder, and granular materials can be done with the help of this sensor.

Probe Configurations & Probe Types

• Rigid Probe Type: Solid rod sensing electrode option designed for continuous level transmitter setups in shallow process vessels.
• Flexible Cable Probe: High-tensile stainless steel multi-strand wire rope layout optimized for tall silos as a solid level sensor or for deep industrial sumps.
• Insulation Sleeve Styles: Full PTFE sleeve insulation provided as standard for conducting fluids, or bare stainless steel elements for non-conductive hydrocarbons.

Material of Construction (MOC)

• Sensing Rod/Cable Metallurgy: High-purity SS304 or SS316 stainless steel options.
• Process Mounting Interfacing: Fabricated using rugged SS304, SS316, or specialized Hastelloy alloys.
• Insulation Barriers: Pure Virgin PTFE (Teflon) sheath lining to shield against aggressive media.

Process End Connections & Mounting

• Threaded Process Ports: Male or Female threaded connection interfaces available in standard BSP or NPT sizes ranging from 1/2″ to 2″.
• Flanged Mounting Profiles: Mating flanges manufactured to match international ANSI, ASA, or DIN dimensional sizing specifications.
• Sanitary Mountings: Tri-clover (TC) clamp connections for specialized food or high-purity processing pipelines.

Operating Parameters & Environment

• Process Pressure Capability: Mechanical construction rated to safely withstand operating pressures up to 40 Kg/cm².
• Process Temperature Range: Specially engineered to function as a capacitive level indicator for high temperature liquids operating up to 200°C.
• Medium Compatibility Calibration: Factory-configured variants optimized to serve as a capacitance level sensor for diesel tank operations, a capacitance sensor for sticky slurries, or a capacitive level transmitter for corrosive acids.

Power Supply & Housing Architectures

• Primary Power Requirement: 24 VDC Isolated external power line connection loop.
• Enclosure Safety Ratings: Heavy-duty Die-cast aluminum weatherproof IP65 housing or certified explosion-proof flameproof terminal enclosure.

Signal Outputs & Local Display Interfaces

• Analog Current Loops: Outfitted with an active capacitive level transmitter 4 20ma output loop for real-time DCS/PLC linkups.
• Digital Communication Bus: Optional RS485 Modbus RTU serial interface module for remote automated automation systems.
• Visual Display Upgrades: Available configured as a capacitive level probe with local display utilizing an integral digital LCD panel showing instantaneous percentage or volumetric metrics.

Accurate Measurement for Tough Media: Capacitive Level Sensor measures liquid, slurry, powder, and granular medium without any moving parts that can contribute to stable level measurement in tough processing environments.

Corrosive Process Media Friendly: The sensor offers PTFE insulated probes with anti-corrosive design, which allows measuring acids, chemicals, and other tough process media.

Simple System Installation: The sensor comes with a standard 4–20 mA output, which facilitates its integration with the PLC, DCS, SCADA, and other control systems.

Industrial Processes Friendly: Solid-state design allows the sensor to operate reliably under varying process temperature and tough operating conditions.