Magnetic Float Sensor FS37A (Vertical)

What Is a Magnetic Float Sensor (Vertical)?

• A magnetic float sensor (or float switch) is a liquid level detection device that opens or closes a switch based on the height of a liquid.

• It works using a magnet inside a floating body that moves with the liquid level. As the float rises or falls, it activates an internal reed switch inside the stem.

• Vertical float sensors are typically mounted vertically in tanks or containers to measure level changes.

Key Features

• Simple Mechanical Design: No need for external power; it functions as a mechanical switch.

• Digital Output: Acts as a digital on/off switch depending on liquid level.

• NO/NC Switch Configurable: By changing the orientation u can set it as Normally Open (NO) or Normally Closed (NC).

• Compact & Lightweight: Small physical size (~4517mm) and light weight (50g).

• Low Current Capacity: Can switch small currents (~0.5A maximum) suitable for interfacing with relays or controllers.

• Voltage Handling: Usually capable of switching up to ~220V AC in simple applications (relay recommended for higher loads).

How It Works

• The float contains a magnet that moves up and down with liquid level changes.

• Inside the stem (vertical tube), there's a reed switch sealed inside.

• When the float magnet approaches the reed switch, it closes the switch (or opens it, depending on orng>controller, alarm, pump circuit, or relay to activate actions (e.g., turn pump ON/OFF).

Typical Specifications (General)

• Sensor Type: Magnetic float level switch (reed switch based).

• Output: Digital open/close contact.

• Contact Rating: ~10W power handling.

• Switching Voltage: Up to ~220V AC (for simple loads).

• Switching Current: Around 0.5A maximum (use a relay for higher loads).

• Contact Resistance: Low (100m).

• Dimensions: Compact vertical body (~4517mm typical).

• Weight: ~50g.

Common Uses

• Water Tank Level Monitoring: Detect ond Level Control: Trigger alarms or control devices based on water level.

• Hydroponics & Gardening Systems: Monitor solution levels.

• Household & Industrial Applications: Used in filtration, heating systems, ice machines, and fluid handling.

Important Notes

• Drive Load with Relay: The sensor can only directly switch small currents; for motors or high loads, use a relay or contactor.

• Mounting Orientation Matters: Designed for vertical installation ensure proper positioning for accurate level detection.

• Float Position Changes Output: Flipping the float or sensor orientation can change between NO and