Question 1

Magnetic flap level meter

Accepted Answer

Principle: The principle of the connector. Developed according to the principle of buoyancy and magnetic coupling.

When the liquid level in the container under test rises and falls. The permanent magnet steel in the float is transmitted to the magnetic flip column indicating panel through magnetic coupling. Flip the red and white columns over 180°.

The column turns from white to red when the liquid level rises.
The column turns from red to white when the liquid level drops.

The junction of red and white on the panel is the actual height of the liquid level in the container, so as to realize the liquid level display.

Question 2

float level meter

Accepted Answer

The structure of the float level meter is mainly designed and produced based on the principles of buoyancy and static magnetic field.

The position of the float with a magnet (abbreviated as float) in the measured medium is affected by buoyancy: changes in the liquid level lead to changes in the position of the magnetic float.

The magnet and sensor (reed switch) in the floating ball act to change the number of components (such as fixed-value resistors) connected in series to the circuit, thereby changing the electrical quantity of the instrument circuit system.

That is, the change of the position of the magnetic float causes the change of the electrical quantity.

The liquid level in the container is reflected by detecting the change of the electrical quantity.

Extended Reading: What is level transmitter working principle?

Question 3

Steel belt level meter

Accepted Answer

It is designed and manufactured using the principle of mechanical balance.

When the liquid level changes, the original mechanical balance will reach a new balance through the movement of the steel belt under the disturbance of the buoyancy of the float.

The liquid level detection device (float) drives the steel belt to move according to the liquid level. The displacement transmission system drives the transmission pin to rotate through the movement of the steel belt. It then acts on the counter to display the liquid level.

Question 4

radar level meter

Accepted Answer

The radar level meter is a measuring instrument based on the principle of time travel. The radar wave runs at the speed of light, and the running time can be converted into a level signal by electronic components.

The probe emits high-frequency pulses and propagates along the cable probe. When the pulses meet the surface of the material, they are reflected back and received by the receiver in the instrument. The distance signal is converted into a level signal.

Extended Reading: Influence of Dielectric Constant on Liquid Level Measurement | Radar-Guided Wave Radar Level Meter

Question 5

Magnetostrictive Level Transmitter

Accepted Answer

When the sensor of the magnetostrictive level transmitter works, the circuit part of the sensor will excite a pulse current on the waveguide wire. When the current propagates along the waveguide wire, a pulse current magnetic field will be generated around the waveguide wire.

There is a float outside the sensor rod of the magnetostrictive liquid level gauge. This float can move up and down along the rod with the change of the liquid level.

Inside the float there is a set of permanent magnetic rings.

When the magnetic field of the pulse current meets the magnetic field of the magnetic ring generated by the float, the magnetic field around the float changes so that the waveguide wire made of magnetostrictive material generates a torsional wave pulse at the position of the float. The waveguide wire is returned and detected by the detection mechanism.

By measuring the time difference between the pulse current and the torsional wave, the position of the float, that is, the position of the liquid surface, can be accurately determined.

Extended reading: Oil-water interface measurement-Magtech magnetic level indicator

Question 6

RF Admittance Level Meter

Accepted Answer

The radio frequency admittance level meter is composed of a sensor and a control instrument. The sensor can be installed on the roof of the warehouse using rod-type, coaxial or cable-type probes.

The pulse card in the sensor can convert the material level change into a pulse signal and send it to the control instrument. After the control instrument is processed and converted into engineering quantity and displayed, it realizes the continuous measurement of the material level.

Read more about: Capacitive Level Measurement System

Question 7

Tuning Fork Level Meter

Accepted Answer

The working principle of the tuning fork level controller is to make the tuning fork vibrate at a certain resonance frequency through a pair of piezoelectric crystals installed on the tuning fork base.

When the tuning fork is in contact with the measured medium, the frequency and amplitude of the tuning fork will change. These changes are detected, processed and converted into a switching signal by an intelligent circuit.

Question 8

Glass plate level meter (glass tube level meter)

Accepted Answer

The glass plate type liquid level meter is connected to the container through the flange to form a communication device, and the height of the liquid level in the container can be directly read through the glass plate.

Question 9

pressure level transmitter

Accepted Answer

The pressure level transmitter adopts the principle of static pressure measurement.

When the liquid level transmitter is put into a certain depth in the measured liquid.

At the same time as the pressure on the liquid surface of the sensor, the pressure of the liquid is introduced into the positive pressure chamber of the sensor through the air-conducting stainless steel. Then the atmospheric pressure Po on the liquid surface is connected to the negative pressure chamber of the sensor to offset the Po on the back of the sensor.

The pressure measured by the sensor is: ρ .g.H , and the liquid level depth can be obtained by measuring the pressure P .

Question 10

Capacitive Level meter

Accepted Answer

Capacitive level meters measure the level of liquid level by measuring changes in capacitance.

It is a metal rod inserted into the liquid container. The metal rod is used as one pole of the capacitor. The wall of the container is used as the other pole of the capacitor.

The medium between the two electrodes is the liquid and the gas above it.

Because the dielectric constant ε1 of the liquid and the dielectric constant ε2 on the liquid surface are different. For example: ε1>ε2.

Then when the liquid level rises, the total dielectric constant value between the two electrodes of the capacitive liquid level gauge increases accordingly and the capacitance increases.

Conversely, when the liquid level drops, the value of ε decreases, and the capacitance also decreases.

Therefore, the capacitive liquid level meter can measure the level of the liquid level through the change of the capacitance between the two electrodes.

Question 11

Intelligent electric displacer level meter

Accepted Answer

The intelligent electric displacer liquid level meter is a liquid level measuring instrument designed according to Archimedes' law and the principle of magnetic coupling. The instrument can be used to measure the liquid level, boundary level and density, and is responsible for the output of upper and lower limit alarm signals.

Question 12

buoy level meter

Accepted Answer

It is designed and manufactured using the principle of mechanical balance.

When the liquid level changes, the original mechanical balance will be disturbed by the buoyancy of the float. The new balance will be achieved by the movement of the steel belt (rope).

The liquid level detection device (float) drives the steel belt (rope) to move according to the liquid level. The displacement transmission system drives the on-site indicating device through the movement of the steel belt (rope), and then displays the liquid level on the display device.

Question 13

Displacer Level Transmitter

Accepted Answer

The pontoon is submerged in the liquid in the pontoon chamber and is rigidly connected to the torsion tube system. The force on the torsion tube system is the net weight of the pontoon minus the buoyancy on the pontoon. Under the action of this combined force, the torsion tube is twisted by a certain angle.

Changes in the position, density or boundary level of the liquid in the buoyancy chamber cause the buoyancy force of the buoyancy immersed in the liquid to change, so that the twisting angle of the tube also changes.

This change is transmitted to a sensor rigidly connected to the torsion tube. Change the sensor output voltage. Then it is amplified by electronic components and converted into 4-20mA current output.

Displacer level transmitters use microcontrollers and associated electronics to measure process variables. Provides current output. Drive LCD display and provide HART communication capability.

Question 14

Magnetic two-color electronic level meter

Accepted Answer

The magnetic-sensitive electronic two-color liquid level meter is made of high-quality stainless steel and imported electronic components.

The display part adopts high-brightness LED two-color light-emitting tube to form a columnar display screen.

Through the red and green changes of the LED light column, the upper and lower limit alarm and control of the liquid level can be realized.

Question 15

External level meter

Accepted Answer

The external liquid level meter is an instrument that measures the liquid level from the outside of the container using the principle of sonar ranging and "micro-vibration analysis" technology.

Two small external level gauge ultrasonic sensors are installed on the bottom of the tank and the other on the side wall of the tank to compensate for density changes.

The signal of the external level meter sensor is converted by the microprocessor and output to the local display or user control system. Can calculate the height of the liquid in the tank and the volume of the liquid in the tank

Question 16

Hydrostatic level transmitter

Accepted Answer

The hydrostatic level transmitter encapsulates the diffused silicon oil-filled core in a stainless steel shell.

The front protective cap protects the sensor diaphragm. It can also make the liquid contact the diaphragm smoothly. The water wire is sealed with the housing. The ventilation tube is connected to the outside world in the cable. The internal structure is designed to prevent condensation.

Question 17

Ultrasonic Level Sensor

Accepted Answer

Ultrasonic level Sensor is composed of a complete ultrasonic sensor and control circuit.

The ultrasonic wave emitted by the ultrasonic sensor is reflected by the liquid surface. The time required to return is used for calculation.

The temperature influence in the ultrasonic transmission process is corrected by the temperature sensor, which is converted into the distance between the liquid surface and the ultrasonic sensor.

Output 4mA-20mADC analog signal through LCD screen. Realize remote reading of field instruments.

Read More about: How to Choose Explosion Proof Ultrasonic Level Sensor?

Question 18

Differential pressure level transmitter (double flange level meter)

Accepted Answer

The differential pressure liquid level transmitter is an electrical component that measures the high and low pressure difference, and then converts it into a current signal by the conversion component and transmits it to the control room.

Differential pressure liquid level transmitter is mainly used for liquid level measurement of closed pressure vessels.

The size of the differential pressure also represents the size of the liquid level height.

Use a differential pressure gauge to measure the differential pressure between the gas and liquid phases to know the liquid level.

Question 19

How do you test liquid nitrogen levels?

Accepted Answer

The general liquid nitrogen tank can have its own liquid level indicator.
Some industrial liquid nitrogen storage tanks, without liquid level display, can be equipped with our very low temperature liquid nitrogen liquid level sensor. Local display is supported. At the same time, it supports signal output, which can be connected to the recorder or the user's monitoring system.

Extended reading: Nitrogen Gas Rotameter

Question 20

What is the pressure in a liquid nitrogen tank?

Accepted Answer

The design temperature of the liquid nitrogen tank is -196°C. There are two kinds of conventional pressures designed, one is 0.8MPa and the other is 1.6MPa. These two design pressures are based on usage needs.

When nitrogen is under pressure, the temperature reaches -196°C. It will become a dark blue liquid, which is liquid nitrogen. Liquid nitrogen can be stored under pressure or without pressure.

Of course, users can also measure the pressure for liquid nitrogen storage tanks according to their own needs. Just use our Cryogenic Pressure Transducer.

Question 21

What are the two types of level sensor?

Accepted Answer

If you want to divide the level sensor into two categories. Then it can be divided into contact type and non-contact type liquid level sensor according to the measurement of whether it is released from the medium.

Extended reading: Non Contact Level Transmitters: Types & Industrial Applications

Question 22

How does the level sensor work?

Accepted Answer

There are 7 main types of level transmitters that Sino-Instrument offers. Each type of transmitter works in a different way, and makes it useful for different types of processes.

Read more about: What is level transmitter working principle?

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