# Explain the difference: Float level sensor, Float level switch and Float level controller

Float level switch, Float level sensor and Float level controller are commonly used liquid level monitoring instruments.

Users are consulting on float level timing, and often confuse it with float level switches and float level gauge controllers. But because they are not the same product, their functions and prices are quite different. So, what are the differences between the float level gauge, the float level switch and the float level controller?

Generally speaking, the main differences between float level gauge, float level switch and float level controller are as follows:

## 1.Float level sensor, Float level switch and Float level controller Structure difference

Float level gauges are generally straight rod type. A maglev ball is placed on the straight rod, and the reed switch in the straight rod can be attracted by moving the maglev ball up and down. The purpose of increasing the resistance value in series is achieved by attracting the reed switch. Because the output 4-20mA remote signal is a current signal, under the condition of a certain voltage, the current is proportional to the resistance. The greater the resistance, the greater the current. Therefore, there is a series circuit board circuit inside the straight rod of the float level gauge.

The reed switch is directly placed inside the float level controller, without the need to design a circuit board separately.

The structure of the float level switch is the simplest.

Float level sensor can also be used with paperless recorder.

Extended reading: Float Level Sensors – Single and Multipoint

## 2.Float level sensor, Float level switch and Float level controller Price difference

Because the structure of the float level gauge is more complicated, its price is relatively high. The price of float level controller is second, and the price of float level switch is the cheapest.

Extended Reading: GWR Level Sensor for High Temperature & High Pressure

## 3.Float level sensor, Float level switch and Float level controller Functional difference

Float Level Gauge A level gauge that can measure liquid level values. The float level controller cannot display the specific level value. Only one switch value alarm point signal is given.

The float level switch is especially suitable for use in small tanks, but you need to open the hole at the height you need. Then install one end of the float at the position where the alarm is needed. When the liquid level reaches the position, the floating ball will be lifted up and the contact point will be automatically disconnected to act as an alarm.

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

## Featured Float level sensor, Float level switch and Float level controller

The customer consults the float level gauge, and the salesperson asks for detailed parameters. The customer just said that it needs 8 on-off alarm points with a measuring length of 5 meters, and nothing else. Our sales staff made a quotation based on this parameter.

After the quotation. Suddenly, the customer asked for a 4-20mA remote signal with a secondary display meter. In this way, the price of the second quotation more than doubled. Customers began to question the price.

Customers think this is the same product. Why does one more parameter make people feel that they are completely two products? This requires customers to clearly understand the specific differences between the float level gauge, the float level controller, and the float level switch.

The float level gauge is used as a level gauge that can measure the liquid level value. Float level gauges are generally straight rod type. A maglev ball is set on the straight rod. Move the maglev ball up and down to attract the reed switch in the straight rod. The purpose of increasing the resistance value in series is achieved by attracting the reed switch.

Because the output 4-20mA remote signal is a current signal. In the case of a certain voltage, current and resistance are proportional. The greater the resistance, the greater the current. Therefore, the float level gauge has a series circuit board circuit inside the straight rod, so the price is relatively high.

And if there is no need to display the specific level value, then there is no need to output a 4-20mA signal to the secondary instrument in the straight rod of the float level gauge. It only needs to be able to give a switch alarm point signal. Then the reed switch can be placed directly inside the float level gauge, without the need to design the circuit board separately. This way the price will be different. Of course, the name becomes the float level controller. So the price is different.

Many customers will also say that it is the float level gauge that they are looking for when they buy it. In fact, to be more precise, this cannot be called a float level gauge. Because it no longer has the function of measuring liquid level value.

The float level switch is simpler than this, and the structure is simpler. Especially suitable for use in small tanks. The float level switch needs to make a hole at the required height by itself, and then install the float at the position where the alarm is needed. When the liquid level reaches the position, the floating ball will be lifted up and the contact point will be automatically disconnected to act as an alarm.

Extended reading: Ultrasonic level transmitter for Hazardous Liquids

## What is float level switch?

The float level switch is a simple-structured medium level measurement, using a level controller that is easy to install. Because the installation has no complicated circuits, the operation is not affected. The user only needs to select the correct material when selecting the model. It is suitable for measuring liquid, pressure or temperature in any environment.

Liquid level switches are widely used in industrial equipment, agricultural equipment, and household appliances. The main structure of the float liquid level switch is composed of a magnetic reed switch and a float. The float has magnetic materials. When the float moves up and down with the measured liquid level, the magnetic reed switch is touched to detect the liquid level position.

Read more about: 😉Liquid level float switch technology|continuous-point level

## What is a normally open float switch?

Float type liquid level switch can choose the open and close type of contact when ordering. Normally open or normally closed

Extended reading: Magnetostrictive Hydraulic Cylinder Position Sensor

## How do float level sensors work?

Float level meter is an instrument for measuring liquid level. It is widely used in the field of liquid measurement. Many industries will choose to use it for measurement equipment. Such as the petroleum, chemical, and pharmaceutical industries.

Float level sensor: Float level sensor is designed and produced based on the principle of buoyancy and static magnetic field. The position of a floating ball with a magnet (floating ball for short) in the measured medium is affected by buoyancy.

The change of the liquid level causes the position of the magnetic float to change. The role of the magnet and sensor (reed switch) in the floating ball changes the number of components (such as fixed resistance) connected in series to the circuit. Thereby changing the electrical quantity of the instrument circuit system. That is, changes in the position of the magnetic float cause changes in the electrical quantity. The change of the electrical quantity is detected to reflect the liquid level in the container.

The float level sensor is installed on the top of the container through a connection flange. The float ball floats on the liquid surface according to the principle of discharging the liquid volume phase and so on.

When the liquid level of the container changes, the float ball also moves up and down. The reed switch of the ball level gauge is magnetically attracted to change the position of the liquid level into an electrical signal. The actual position of the liquid is displayed digitally by the display instrument. The floating ball level gauge can achieve long-range detection and control of the liquid level.

Guess you like: Float Level Sensor Operating Principle

## Float level switch working principle

The float level switch is actually equivalent to a limit switch.

When the liquid level is low, the low liquid level switch is closed to control the water pump to turn on and add water.

When the high liquid level is reached, the high liquid level switch is closed to control the water pump to stop.

Different float level switches are different, some are normally open and some are normally closed. Just pay attention when wiring.

The principle of the float switch is as follows:

Liquids have buoyancy, and the float system (generally with corresponding auxiliary equipment) is made according to the buoyancy of the liquid.

When the liquid level rises, the float system rises accordingly, and similarly when the liquid level falls, it also drops accordingly.

When it rises or falls to the set position, the float system will hit the limit switch (or other microelectronic equipment) in the set position.

So that the travel switch sends out an electric signal, and the electric control device will act immediately when receiving the electric signal, cut off or connect the power supply, forming an automatic control system.

It is basically a reed switch structure, with a movable float on the outside and a magnet inside the ball. When the magnet gets close to the reed pipe by buoyancy, the contacts in the reed pipe are turned on or off.

The principle of the reed switch is to repel the same magnetic poles and attract different magnetic poles.

The switch of the reed switch in the liquid level switch controls the corresponding operating mechanism to form a complete set of circuits. Such as: liquid level display, automatic liquid filling, liquid full alarm and so on.

Extended reading: Capacitive water level sensor

You may like:

Sino-Inst offers over 10 Float level switches and transmitters for level measurement. About 50% of these are float liquid level meters, 40% is the level switches.

A wide variety of Float level switches and sensors options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Float level switches and sensors instrumentation, located in China.

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