Product Overview

This liquid level transmitter uses a high-performance diffused silicon piezoresistive pressure sensor as the measuring element to accurately measure the hydrostatic pressure of the liquid, which is directly proportional to the liquid level depth, and converts it into a standard (current or voltage) signal output through a signal conditioning circuit, establishing a linear corresponding relationship between the output signal and the liquid depth, thereby realizing the measurement of liquid depth. The product features high accuracy and small size, and can be directly immersed in the liquid to measure the liquid height from the end of the transmitter to the liquid surface, making it convenient to use. It is suitable for liquid level measurement and control in petroleum, chemical, power plant, urban water supply, and hydrological survey fields.

Product Features

With this structure, the sensor part immersed in the liquid is a fully sealed stainless steel structure, and the electronic circuit housing is a cast aluminum structural part, installed in a location convenient for wiring, making calibration and wiring easy;

Performance Parameters

Measuring range:         0～0.5m…200m water column                       

Pressure type:         gauge pressure, absolute pressure                             

Power supply:         24VDC、12VDC                           

Output signal:         4～20mA、1～5V、0～5V                   

Compensation temperature:         -10～70℃                               

Operating temperature:         -40～85℃                               

Storage temperature:         -40～125℃                             

Zero temperature drift:     ±2%FS                                 

Sensitivity temperature drift:   ±2%FS                                 

Overload pressure:         150%FS                                 

Mechanical vibration:         20g（20-5000HZ)                         

Shock:             100g（11ms）                           

Overall accuracy:         0.1、0.3、0.5 class optional                     

Long-term stability:       ±0.2%FS/年                             

Response time:         ≤1ms（rising to 90％FS）                   

Insulation:            100MΩ/250VDC                           

Material:             junction box low-copper aluminum alloy; liquid level probe all stainless steel     

                   cable material polyurethane lead wire                     

Media compatibility:         various media compatible with 316L stainless steel             

Protection rating:         IP65                                   

Working Principle

Based on the hydrostatic pressure measurement principle

When the liquid level transmitter is immersed to a certain depth in the measured liquid, the pressure on the liquid-facing surface of the sensor is P=p.g.H+PO, where:

P: pressure on the liquid-facing surface of the sensor　　　　　　 unit: Pa

p: density of the measured liquid,　　　　　　　　　　　 unit: kg/m3

g: local gravitational acceleration,　　　　　　　　　　 unit: m/s2

Po: atmospheric pressure above the liquid surface,　　　　　 unit: Pa

H: depth of the sensor immersed in the liquid　　　　　　 unit: m

At the same time, the atmospheric pressure PO above the liquid surface is introduced into the back pressure chamber of the sensor through the vented cable to offset the PO on the liquid-facing surface of the sensor, so that the pressure measured by the sensor is: P=O.gH. Obviously, by measuring the pressure P, the liquid level depth H can be obtained, and the pressure signal detected by the sensor is converted and amplified by the circuit and output as a standard signal after compensation

Product Categories

Submersible, straight rod, flange, threaded, capacitive, screw-in, and float-ball structure designs are available, with anti-clogging design, simple installation, convenient use, strong interchangeability, high sensitivity of high-quality sensors, fast response speed, accurate reflection of subtle changes in flowing or static liquid levels, and high measurement accuracy.

This new type of transmitter is manufactured using advanced foreign technology and equipment. Key raw materials, components, and parts are all imported. The whole unit undergoes strict assembly and testing. This product features advanced design principles, complete varieties and specifications, and easy installation and use.

The submersible liquid level transmitter uses a high-performance diffused silicon piezoresistive pressure sensor as the measuring element. Through highly reliable amplification processing circuits and precise temperature compensation, it converts the gauge pressure or absolute pressure of the measured medium into standard voltage or current signals. This product is compact and easy to install and use, and can be directly immersed in water to measure the liquid level height to the liquid surface.

Features: adopts advanced circuit processing technology, with stable performance and high sensitivity; multiple measuring ranges are available, with a maximum measurement of 200m (water column pressure); adopts a 316L stainless steel isolation diaphragm, suitable for a variety of measured media; flexible configuration, with different configurations selectable according to requirements.

Product Applications:

Liquid level measurement and control in industrial sites, urban water supply and sewage treatment, petroleum, chemical, power plants, hydrological monitoring, reservoirs, dams, hydropower construction, and other fields.

Product features: with reverse polarity and current limiting protection; laser trimmed temperature compensation, zero point and range can be adjusted on site; wide range and corrosion resistance, suitable for a variety of media; strong overload and anti-interference capability, stable performance.

Extended Products

Lightning protection liquid level transmitter folding

The lightning protection liquid level transmitter encapsulates the OEM oil-filled core inside a stainless steel housing. The protective cap at the front end protects the sensor diaphragm and also allows the liquid to smoothly

contact the diaphragm. The waterproof lead wire is sealed and connected to the outer shell, and the vent tube communicates with the atmosphere inside the cable. The internal structure is designed to prevent condensation. In addition, a three-stage lightning protection module is designed in the internal circuit, which can effectively prevent damage from induced lightning.

Armored liquid level transmitter folding

This product can be directly inserted into the bottom of the liquid to measure the height from the end sensor to the liquid level surface. It is easy to install and highly reliable, suitable for liquid level measurement in open containers or applications requiring insertion installation.

Advantage Analysis

The liquid level transmitter can convert changes in various material level parameters into standard current signals, remotely transmit them to the operation control room for centralized display, alarm, or automatic control by secondary instruments or computers. Its excellent structure and installation method make it suitable for continuous detection of liquid level, material level, or object level under special conditions such as high temperature, high pressure, strong corrosion, easy crystallization, anti-clogging, anti-freezing, as well as solid powder and granular materials. It can be widely used in detection and control in various industrial processes.

After-sales Service

I. Quality Assurance Service 

(1) Product quality is subject to the three guarantees 

  The product warranty period is one year from the date of delivery. During the warranty period, if there is a quality problem with the product itself, our company will provide free repair, replacement, and return services. 

   1、If general components of the product fail and can be restored to meet usage requirements after replacement, we will be responsible for free scheduled repair; 

   2、If major components of the product fail and cannot be repaired on schedule, qualified products of the same model and specification will be replaced; 

(2) Disclaimer scope 

  During the warranty period, product failures caused by the following human factors and force majeure factors are not covered by the free repair, replacement, and return service scope:

   1、The usage occasion is inconsistent with the parameters in the order contract;

   2、Improper use by the customer causes product failure; 

   3、The customer repairs and modifies the product without authorization; 

   4、The product appearance is severely damaged or deformed, the product identification is lost, and the product source cannot be identified; 

   5、Product damage caused by earthquakes, floods, fires, and other natural disasters; 

   6、Human factors. 

II. Lifetime product maintenance service 

 For faulty products beyond the warranty period and within the disclaimer scope, our company will provide lifetime maintenance for your products, only charging maintenance cost fees and product transportation fees. 

Since its establishment, Xi'an Shenghongchuang Instrument Co., Ltd. has mainly engaged in the R&D and production of pressure, liquid level, temperature, differential pressure, digital display, weighing, and flow instruments. Main products include Swiss metallux ceramic piezoresistive sensors and self-developed ceramic capacitive pressure sensors. Diffused silicon, ceramic piezoresistive, strain gauge, metal capacitive, ceramic capacitive pressure transmitters, remote pressure transmitters, high-temperature pressure transmitters, flush diaphragm pressure transmitters, anti-corrosion pressure transmitters, integrated/split liquid level transmitters, anti-corrosion liquid level transmitters, lightning protection liquid level transmitters, high-temperature guided-pressure liquid level transmitters, straight rod liquid level transmitters, flange liquid level transmitters, wind pressure transmitters, metal capacitive differential pressure transmitters, diffused silicon differential pressure transmitters, pressure controllers, thermocouples/RTDs, temperature transmitters, and ultrasonic level meters.

Precautions 1.All supplied products are provided with product certificates and instruction manuals, including product number, technical parameters, wiring, factory date, etc. Please check carefully to avoid misuse. 2.Wiring should be carried out strictly in accordance with our company's instructions for use. 3.This product is a precision instrument. Random disassembly, collision, dropping, and poking the sensor with sharp tools are prohibited. 4.The transmitter can work immediately after power-on, but the output becomes stable after 30 minutes of preheating. 5.If any abnormality is found during use, the power supply should be turned off, use should be stopped, and inspection should be carried out, or contact our company's technical department directly. 6.During transportation and storage, restore the original packaging and store it in a cool, dry, and ventilated warehouse. 7.The quality warranty period is 12 months (damage caused by improper use such as pressure overload and incorrect wiring is not covered by the quality warranty). 8.Special products are customized products and do not participate in the 7-day no-reason return policy. Customized products have a delivery period and are not returnable or exchangeable.