Home > Knowledge > Content
Fault check judgment and treatment of float level switch
Dec 13, 2018

Fault check judgment and treatment of float level switch

The float liquid level switch is a liquid level control device with simple structure and convenient use. It does not need to provide power supply and has no complicated circuit. It has the advantages of smaller volume and longer working life than general mechanical switches.

The working principle of the float level switch:

The magnetic float of the float ball level switch rises or falls with the liquid level, so that the sensor detects the position of the reed switch chip in the tube, and sends a contact opening (off) switching signal.

Fault check judgment and treatment of float level switc

One or more reed switches are installed in the closed non-magnetic tube, and then the tube is passed through one or more floating balls with hollow magnets inside, and the rise or fall of the liquid will move the floats up and down together. Thereby causing the reed switch in the non-magnetic tube to actuate or disconnect, thereby outputting a switching signal

Technical advantages of the float level switch:

The float switch does not contain components that cause malfunctions and bellows, springs, seals, etc. Instead, a straight float is used to drive the internal magnet of the switch, and the simple lever of the float switch causes the switch to act instantaneously. The float cantilever angle is designed to prevent the float from being vertical. The float level switch is a liquid level controller with simple structure, convenient use, safety and reliability. It is faster than the general mechanical switch and has a long working life. Compared with the electronic switch, it has the characteristics of strong anti-load shock capability, and one product can realize multi-point control. It has been widely used in shipbuilding, paper making, printing, generator equipment, petrochemical, food industry, water treatment, electrician, dye industry, hydraulic machinery and so on. The float switch is a liquid level control device with simple structure, convenient use, safety and reliability. It has smaller volume, faster speed and longer service life than general mechanical switches. Compared with electronic switches, it has strong anti-load shock resistance. Features.

Float level switch classification:

1. Stainless steel float switch

The universal stainless steel float level switch provides both vertical and horizontal mounting configurations with a single 30VA or 100VA reed switch output for reliable level detection of relatively clean water, dilute chemicals and light oil. Suitable media include deionized hot water and cooking oil. Stainless steel level sensor can be installed vertically in the tank or horizontally on the tank wall for high level or low level alarms

2. Connecting rod float level switch

The connecting rod float level switch kit reliably detects multiple levels of relatively clean water, dilute chemical solvents and light oil with a maximum range of 8' (2.44 m). The 1-5-way reed switch output is used, and the integrated collector terminal box has an integrated wiring terminal. The float level switch is made of stainless steel and is suitable for level measurement in high temperature or high pressure process tanks.

3. Magnetic float ball level switch

Float switches are often used in the control of tank levels. No external power supply, side or top mounting, wide temperature and pressure range, a wide range of process connections, stainless steel wetted parts and explosion-proof design for a wide range of applications.

4. Side mounted float switch

Magnetic side-mounted float switches are often used in the control of tank level. The side-mounted float switch has no external power supply, side or top mounting, wide temperature and pressure range, a wide variety of process connections, stainless steel wetted parts and explosion-proof design making it a universally applicable float level switch.

5. Cable float level switch

The float level switch has two chambers that are completely sealed using a special process when processing the cable float switch. Different switching points can be adjusted by the counterweight of the cable end. Non-toxic and mercury-free, the cable float level switch can be used in drinking water.

6. Multi-point stainless steel float switch

Float switches are used for FM and CSA certified explosion proof applications and general environmental applications. The float switch provides up to 4 switch points for PLC or SCADA remote device prosecution. Multi-point stainless steel float switches are typically used in high temperature and/or high pressure process tanks and require an explosion-proof certified environment.


Fault check judgment and treatment of float level switc

 Fault check judgment and processing:

     1 float is stuck

The fault phenomenon is that the alarm light of the control room is always on, or the liquid level is too high or too low, and neither alarm nor any switching action. The floating ball is mostly caused by oil stains and impurities on the surface of the measured liquid level. It often occurs in winter. When the liquid level drops, some of the oil and impurities on the upper part will accumulate at the connection between the floating ball and the lever, causing the floating ball to fail. Work, such faults often occur in controllers that detect high levels. Raise the liquid level beyond the float ball, melt the oil impurities with the liquid temperature in the container, and the float ball can resume operation.

     The controllers that detect low liquid levels are mostly those in which too much sludge in the container causes the float to become stuck. This kind of failure can only remove the sludge in the container after the tower can be deactivated.

Fault check judgment and treatment of float level switc

     2 float off

     For instruments with a long service life, the floating ball is detached due to corrosion of the connection of the float ball, and can only be handled when the tower and tank equipment are shut down.

    3 magnetic steel demagnetization

    For a long time of use, the magnetic properties of the magnetic steel at the end of the float will be weakened. When the float is floating up and down, there is not enough magnetic force to repulsion the same magnetic pole magnet 2 to swing up and down, so that the state of the micro switch cannot be Switching, the switch is lost, and only the float level controller can be replaced.

3 switch false alarm, malfunction

It may be that the micro switch has poor contact due to oxidation and corrosion, poor contact of the wire, and failure caused by the water in the terminal. After the power is off, the multimeter is used to measure the resistance between the switch and the wire, or the insulation resistance of the wire to the ground.

Improper installation position, the liquid level controller is installed near the liquid inlet and outlet, affected by the rapid flow of liquid, the liquid level fluctuation will be very large, so that the fluctuation of the float ball becomes large, resulting in frequent switching action and this failure, thoroughly To solve the problem, only re-select the installation position of the float level controller.