Comprehensive Guide to Submersible Level Transmitters: Nexisense Brand Overview

In modern industrial production, liquid level measurement is a critical factor in ensuring process safety and efficiency. Imagine a large water treatment plant where inaccurate level monitoring could lead to overflow or equipment damage, resulting in economic losses and safety hazards. As a reliable measurement tool, the submersible level transmitter is increasingly becoming the preferred choice for engineers. It not only accurately captures changes in liquid height but also adapts to various complex environments.

As a brand focused on sensor technology, Nexisense has introduced a series of submersible level transmitters that help numerous enterprises optimize production processes through their stability and durability. This article starts with basic concepts and gradually explores the working principles, types, applications, and practical operation techniques, providing you with a comprehensive reference.

Basic Concept of Submersible Level Transmitters

A submersible level transmitter, as the name implies, is a device that is directly “submerged” in liquid for measurement. Essentially, it is a pressure transmitter specifically designed for level detection. Unlike traditional float-type or ultrasonic level meters, this type of transmitter utilizes the linear relationship between hydrostatic pressure and liquid height to achieve precise non-contact measurement.

In simple terms, when the sensor is immersed at the bottom of a liquid, the pressure it senses directly reflects the liquid level. Nexisense submersible level transmitters use advanced diffused silicon or ceramic capacitive sensing elements that convert pressure signals into standard electrical signals such as 4–20 mA current output or digital protocols.

These devices are typically suitable for monitoring liquids in open or closed containers. The measured media can include water, oil, and even certain viscous substances, as long as they are compatible with the sensor materials. Key advantages include easy installation, no need for additional mounting brackets, strong anti-interference capability, and suitability for long-term submersion.

In real-world scenarios, these transmitters are commonly used to monitor water tanks, rivers, or chemical storage tanks. For example, in municipal water supply systems, they provide real-time feedback on water level changes, enabling operators to adjust pump station operation in a timely manner to avoid waste or shortages.

Compared with other types of level meters, submersible transmitters are sensitive to medium density. Therefore, liquid properties must be considered during design, but this also gives them greater adaptability.

Working Principle Explained

The core principle of a submersible level transmitter is derived from fluid statics: the static pressure P at a certain point in a liquid equals the product of liquid density ρ, gravitational acceleration g, and liquid height h, namely P = ρgh. By measuring the pressure at the bottom, the transmitter can calculate the liquid level height.

Specifically, the sensing element is usually a pressure-sensitive component with an isolated diaphragm structure, such as a diffused silicon piezoresistive sensor. When liquid pressure acts on the diaphragm, it produces slight deformation, which is converted into resistance or capacitance changes.

The built-in amplification circuit then processes the signal, performing temperature compensation and linear correction, and finally outputs a standard signal. Nexisense products incorporate laser trimming technology to ensure stable zero point and sensitivity across a wide temperature range.

For example, when measuring a water tank with a density of 1 g/cm³ and a liquid level of 5 meters, the bottom pressure is approximately 50 kPa. The transmitter converts this pressure into a 20 mA output signal and transmits it to a PLC or controller. If the medium density differs, such as oil with a density of 0.8 g/cm³, calibration parameters must be adjusted accordingly to ensure accuracy.

In addition, modern submersible level transmitters often integrate lightning protection and overvoltage protection functions. Nexisense series products also feature anti-interference frequency-cut designs, ensuring stable output even in industrial environments with strong electromagnetic noise.

This not only improves measurement accuracy (typically up to 0.1% FS) but also reduces maintenance costs.

Main Types and Their Characteristics

According to application requirements, submersible level transmitters can be divided into multiple types, each with unique designs to address specific challenges. Nexisense offers a comprehensive product line, including general-purpose, split-type, and high-temperature models, ensuring users can find a suitable solution.

General-Purpose Submersible Level Transmitter

This type is the most common entry-level choice and is suitable for most standard liquid level measurement scenarios. It uses a diffused silicon pressure sensing element, with the sensor and transmitter connected directly via a cable. Installation simply requires placing the probe at the bottom of the liquid.

Key features include easy cable connection for rapid deployment; integrated chip amplification circuits supporting wide voltage supply (such as 12–36 VDC); anti-clogging and anti-scaling design to reduce contamination; strong anti-interference capability including lightning protection and frequency filtering; built-in reverse polarity, overvoltage, and current limiting protection for safe operation; fast response and high stability, typically with accuracy above 0.25% FS.

Among Nexisense general-purpose products, users report outstanding performance in power engineering projects. For example, in drainage and water supply applications, they can continuously monitor groundwater levels for months without frequent cleaning.

Split-Type Submersible Level Transmitter

The split-type design separates the sensor from the transmitter, connecting them via cable or tubing. This is suitable for applications requiring remote monitoring. It uses Class A diffused silicon elements, and the amplification circuit employs imported German chips, enhancing signal processing reliability.

Advantages include flexible installation, with the transmitter placed in a dry area to avoid moisture impact; anti-clogging, anti-scaling, and anti-interference features similar to general-purpose models; wide voltage supply and protection mechanisms; and fast response suitable for dynamic liquid level changes.

Nexisense split-type transmitters are commonly used in the pharmaceutical industry, such as monitoring liquid storage tanks in pharmaceutical plants. Operators can view data in the control room while the sensor remains submerged in the medium, ensuring hygiene and safety.

High-Temperature Submersible Level Transmitter

For high-temperature media, high-temperature transmitters use imported diffused silicon elements and diaphragm isolation technology, typically connected via stainless steel capillary tubes. This enables them to withstand higher temperatures (up to 150°C), making them suitable for chemical or hot water systems.

Features include high-temperature resistance, anti-clogging, and anti-scaling; integrated chip circuitry; strong anti-interference and protection functions; and current output only, simplifying interfaces.

In Nexisense products, this type performs exceptionally well in high-temperature steam environments, helping users avoid failures caused by thermal expansion in traditional sensors.

In addition to these, Nexisense also offers customized models, such as corrosion-resistant or digital-output versions, to meet specific requirements.

Application Areas

Submersible level transmitters have a wide range of applications, covering almost all industries involving liquid management. In power engineering, they are used for level control in cooling water towers to ensure stable operation of generator units.

In municipal water supply and drainage systems, they monitor reservoir or pipeline water levels to prevent flooding or shortages. In the pharmaceutical industry, they accurately measure liquid levels in drug storage tanks, helping maintain production hygiene standards.

Additionally, in chemical plants, they are suitable for monitoring acidic and alkaline solutions due to stainless steel housings with corrosion resistance. In hydrological exploration, they measure river or well depths to support environmental monitoring projects.

In electromechanical plants and urban water circulation systems, they provide real-time data feedback to optimize energy usage. Nexisense products have been applied in multiple projects worldwide. For example, an Asian water treatment plant used Nexisense transmitters to achieve automated control, reducing manual intervention and improving efficiency.

Overall, these transmitters promote industrial automation and reduce operational risks.

Installation and Maintenance Guide

Proper installation is key to ensuring transmitter performance. First, select an appropriate location: the sensor should be placed at the bottom of the container, avoiding bubbles or turbulence. Cable length should allow sufficient margin based on depth, and the transmitter should be secured with brackets.

Installation steps include removing the protective cap; connecting a 24 VDC power supply and signal lines; slowly immersing the probe into the liquid to avoid twisting; securing the cable to prevent tension; and powering on to test output signals.

For maintenance, regularly check cable insulation and sensor cleanliness. Nexisense recommends annual calibration to prevent drift. If the medium is prone to scaling, clean the diaphragm with a soft brush, avoiding hard objects. During storage, keep the device dry at temperatures between -20°C and 60°C.

In practical operation, users should consider medium compatibility. For corrosive liquids, select models with PTFE coating to extend service life and reduce failures.

Calibration Method

Calibration is an essential step to maintain measurement accuracy. Nexisense transmitters are factory-calibrated, but field calibration is required based on medium density.

Basic procedure: prepare a standard 24 VDC power supply and a precision ammeter (accuracy above 0.2%); remove the protective cap and connect the device; zero calibration: adjust output to 4 mA with no liquid; full-scale calibration: fill liquid to maximum height and adjust to 20 mA; repeat several times to ensure stability; check errors at 25%, 50%, and 75% points.

For non-water media, such as solutions with a density of 1.3, use water of corresponding height for calibration (for example, use 1.3 m of water for a 1 m range). After calibration, tighten the cap and recheck annually.

If integrated into a control system, temperature drift can be compensated via software. Nexisense provides calibration toolkits to simplify the process.

Why Choose Nexisense Submersible Level Transmitters

Among many brands, Nexisense stands out due to technological innovation and user-oriented design. Products use OEM-grade sensors to ensure high accuracy and long service life. Comprehensive protection mechanisms reduce on-site failures.

They support multiple communication protocols, such as HART or Modbus, facilitating integration with existing systems. Nexisense also emphasizes environmental responsibility, using low-power designs compliant with RoHS standards.

Users benefit from customization services and professional support to address specific challenges. Choosing Nexisense is not just about purchasing equipment, but investing in reliable measurement solutions.

FAQ

1. What media are submersible level transmitters suitable for?
They are suitable for water, oil, and pasty substances compatible with 316 stainless steel. They offer certain corrosion resistance, but special models are required for strong acids and alkalis.

2. How do I distinguish between general-purpose and split-type transmitters?
General-purpose models have an integrated design suitable for simple installation. Split-type models separate the sensor and transmitter, suitable for remote monitoring or harsh environments.

3. What temperature can high-temperature transmitters withstand?
Nexisense high-temperature models can withstand temperatures above 150°C, using diaphragm isolation technology suitable for hot water or steam systems.

4. What should be noted during installation?
Ensure the sensor is vertically submerged, avoid cable bending, check sealing to prevent leakage, and consider medium density for pre-calibration.

5. What is the recommended calibration cycle?
Once per year is recommended, or adjusted based on usage environment. For highly corrosive media, calibration every six months is advised.

6. What output signals are available?
Standard output is 4–20 mA current signal. Voltage or digital outputs such as RS485 are also supported.

7. How are anti-interference issues handled?
Nexisense products feature built-in lightning protection and frequency filtering designs, ensuring stable performance in noisy environments. Installation should avoid strong electromagnetic sources.

8. Can they be used in closed containers?
Yes, but atmospheric pressure compensation must be considered. They are typically used in open containers; for closed containers, differential pressure models are recommended.

9. What is the warranty period for Nexisense products?
The standard warranty is one year, with lifetime technical support. Extended warranties may be available depending on usage conditions.

10. How is measurement accuracy ensured?
Accuracy is ensured through temperature compensation, linear correction, and regular calibration, typically maintaining precision within 0.1%–0.5% FS.

Conclusion

As a reliable tool for industrial level measurement, submersible level transmitters have transformed traditional monitoring methods through simplicity and precision. From working principles to practical applications, Nexisense products demonstrate a perfect balance between technology and usability.

Whether general-purpose or high-temperature models, they provide stable support for your projects. With proper installation and maintenance, their value can be maximized to achieve efficient production.

Looking ahead, with the integration of IoT technologies, these transmitters will become even smarter, helping enterprises move toward digital transformation. If you are seeking a reliable level measurement solution, consider Nexisense—not just a device, but a trusted partner.