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ProPak Philippines 2025
February 12-15, 2025
Measurement Technologies Corporation at ProPak Philippines 2025 – Metro Manila, Philippines
Magnetic Float Switch
A magnetic float switch is a highly reliable and cost-effective device used to detect and control the level of liquids in tanks, vessels, and pipelines. Whether used for pump control, overfill protection, or level alarms, it plays a vital role in many industrial, commercial, and residential applications.
What Is a Magnetic Float Switch?
A magnetic float switch is a type of liquid level sensor that uses a magnet embedded in a float and a reed switch inside a sealed stem to detect the presence or absence of liquid. As the liquid level rises or falls, the float moves accordingly, triggering the reed switch when it reaches a specific point.
This switching action can be used to:
Activate alarms
Control pumps
Open/close valves
Send signals to control panels

How It Works
Float – Moves up or down with the liquid level. It is designed to slide along a non-magnetic stem or tube. The float is a hollow component made from buoyant material such as plastic or stainless steel. It contains a small permanent magnet inside.
Reed Switch – A pair of magnetic, flexible metal contacts sealed within a glass tube. When the magnet in the float comes close to the reed switch, the magnetic field causes the reeds to either close (make contact) or open (break contact). This change in state acts as an electrical signal to control or monitor a system.
Switch Activation – As the liquid level rises or falls, the magnet inside the float moves with the liquid. Once the float reaches the switch position, the magnetic field activates the reed switch. The switch state changes from open to closed (or vice versa), sending a signal to connected devices.
Types of Switching Action
Normally Open (NO): The circuit is open until the float rises to the switching point.
Normally Closed (NC): The circuit is closed until the float drops below the switching point.
Some magnetic float switches offer multi-point sensing for high/low level monitoring.
Common Applications
- Water treatment plants
- Oil and chemical tanks
- HVAC systems
- Food and beverage production
- Pumps and reservoirs
- Marine and automotive fuel tanks
Advantages of Magnetic Float Switches
- No power required for basic operation
- Simple design and easy installation
- Highly reliable with minimal moving parts
- Resistant to pressure and temperature extremes
- Low maintenance and cost-effective
Things to Consider When Choosing a Magnetic Float Switch
- Liquid type and compatibility (corrosive, viscous, etc.)
- Mounting style (top-mount, side-mount, vertical)
- Operating temperature and pressure
- Switch rating (voltage/current requirements)
- Material construction (plastic, stainless steel, etc.)
Looking for magnetic float switches?
We supply high-quality float switches for a wide range of applications. Contact us today to find the right model for your system.
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