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 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 to realize liquid level depth measurement. The product features high accuracy and a compact size, and can be directly immersed in the liquid to measure the liquid height from the transmitter end to the liquid surface, making it convenient to use. It is suitable for liquid level measurement and control in petroleum, chemical, power plant, municipal water supply, and hydrological survey fields.

Product Features

With this structure, the sensor part immersed in the liquid is of a fully sealed stainless steel structure, and the electronic circuit housing is a cast aluminum structural component, 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                   

Compensated 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/year                             

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

Using the hydrostatic pressure measurement principle

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

P: pressure on the sensor's pressure-receiving surface　　　　　 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 sensor's back-pressure chamber through the vented cable to offset the PO on the sensor's pressure-receiving surface, 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 sensed by the sensor is converted and amplified by the circuit, then output as a standard signal after compensation

Product Categories

Submersible, straight rod, flange, threaded, inductive, screw-in, and float-type structural designs are available, with anti-clogging design, simple installation, convenient use, strong interchangeability, and high sensitivity of the high-quality sensor. It responds quickly and accurately reflects subtle changes in flowing or static liquid levels, with 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 complete 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 a highly reliable amplification processing circuit 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: advanced circuit processing technology, stable performance, and high sensitivity; multiple measuring ranges, with a maximum measurement of 200m(water column pressure); 316L stainless steel isolation diaphragm, suitable for a variety of measured media; flexible configuration, with different configurations available according to needs.

Product Applications:

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

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

Extended Products

Lightning protection liquid level transmitter folded

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

contact the diaphragm. The waterproof lead wire is hermetically connected to the outer housing, and the vent tube inside the cable communicates with the atmosphere. The internal structure is designed to prevent condensation. A three-stage lightning protection module is also designed in the internal circuit, which can effectively prevent damage caused by induced lightning.

Armored liquid level transmitter folded

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

Advantage Analysis

The liquid level transmitter can convert changes in various level parameters into standard current signals and transmit them remotely 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-blocking, 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 

(I) The 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 product quality problem caused by the product itself, our company provides free repair, replacement, and return services. 

   1、If general parts of the product fail and can be restored to meet usage requirements after replacement, free scheduled repair shall be provided; 

   2、If the main parts of the product fail and cannot be repaired on schedule, a qualified product of the same model and specification shall be replaced; 

(II) Disclaimer scope 

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

   1、The usage conditions are inconsistent with the parameters in the purchase contract;

   2、Product failure caused by improper use by the customer; 

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

   4、The product appearance is severely damaged or deformed, and the product identification is lost, making it impossible to identify the product source; 

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

   6、Human factors. 

II. Lifetime Product Repair Service 

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

Since its establishment, Xi'an Shenghongchuang Instrument Co., Ltd. has been mainly engaged in the R&D and production of pressure, liquid level, temperature, differential pressure, digital display, weighing, and flow instruments. Its 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, air pressure transmitters, metal capacitive differential pressure transmitters, diffused silicon differential pressure transmitters, pressure controllers, thermocouple/RTD temperature transmitters, and ultrasonic level meters.

Precautions 1. All supplied products are provided with a product certificate and instruction manual, including product number, technical parameters, wiring, factory date, etc. Please carefully check them 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, or poking the sensor with sharp tools is prohibited. 4. The transmitter can work immediately after being powered on, but the output becomes stable after preheating for 30 minutes. 5. If any abnormality is found during use, the power 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 wiring errors is not covered by the quality warranty). 8. Special products are customized products, do not participate in 7-day no-reason return, customized products have a delivery lead time, and are non-returnable and non-exchangeable.