High quality ESMDR1000 Capacitance Level Transmitters for liquid solids

This capacitive level meter measures liquid level based on the principle of capacitance sensing, with the core idea being to reflect the height of the liquid level by detecting changes in the capacitance between the two electrodes of the sensor. The specific working process is as follows:

1.Capacitance Formation: The metal probe of the level meter acts as one electrode, while the wall of the measured container serves as the other electrode. The dielectric between the two electrodes consists of the measured liquid and the gas (or other medium) above it.

2.Capacitance Change: Because there is a difference between the dielectric constant ε₁ of the liquid and ε₂ of the medium above the liquid (usually ε₁ > ε₂), when the liquid level rises, the overall dielectric constant between the two electrodes increases, resulting in an increase in capacitance; conversely, when the liquid level falls, the dielectric constant decreases, and the capacitance decreases accordingly.

3. Signal Conversion and Output: The specialized circuitry inside the sensor detects and processes the changes in capacitance, converting them into an electrical signal proportional to the liquid level. After amplification, calibration, and other steps, a standard 4–20 mA analog signal or digital communication signal is output, enabling real-time monitoring and transmission of the liquid level.For conductive measured media, an insulating layer is applied to the surface of the metal probe to prevent direct conduction between the electrode and the medium, ensuring measurement accuracy.

1. Simple structure and low cost
Only a single probe rod is needed, without a complex coaxial sleeve structure, making manufacturing costs low and cost-effective. The probe diameter can be made very thin, resulting in low fluid resistance.

2. Flexible installation and strong adaptability
Utilizing the container wall: For metal containers, the tank itself can be used as the ground electrode, without additional grounding components, making installation extremely simple (just insert through a top opening).
Solutions for non-metal containers: For plastic, fiberglass, and other non-metal containers, a "second electrode" can be created by attaching conductive foil on the outer wall, installing a metal hoop, or adding a grounding rod inside, still allowing the use of a single-electrode probe.

3. Easy to clean and maintain
There are no narrow gaps inside a coaxial sleeve, making it difficult for dirt and grime to accumulate. For viscous, crystalline, or impurity-containing liquids, a single smooth probe (especially one with a PTFE coating) is less likely to have material stick to it, and even if material does stick, it is easier to clean.

4. Wide application range
Can measure conductive liquids (water, acid and alkali solutions) and non-conductive liquids (oil, organic solvents).

1. Water Treatment and Environmental Protection
Wastewater Tank/Water Tank: Measure the level of tap water, sewage, and wastewater.
Acid-Base Storage Tank: Use PTFE-lined probes to measure highly corrosive chemicals (hydrochloric acid, sulfuric acid, sodium hydroxide).

2. Petrochemical Industry
Oil Monitoring: Diesel, gasoline, and lubricating oil storage tanks (non-conductive media).
Reactor: Level monitoring in stirred reactors (single-electrode type with strong anti-interference capability).

3. Food and Pharmaceutical
Hygienic Applications: Stainless steel polished probes for milk, juice, and medicinal liquid tanks.
CIP Cleaning Resistance: Can withstand high-temperature steam and chemical cleaning agents.

4. Special Working Conditions
High-Temperature Molten Salt/Molten Metal: Special models with ceramic-insulated probes.
Deep Wells/Deep Tanks: Flexible cable-type single-electrode probes for wells dozens of meters deep.