Motion-Activated Electromagnetic Shower Valve

Tip: click the sensor or shower area

Animation speed

Motion detectedNO

CircuitOPEN

ElectromagnetOFF

ValveCLOSED

WaterSTOPPED

Correct step-by-step operation

Waiting

The spring holds the valve plate against the valve seat, so water cannot pass.

Motion detected

A person steps underneath. The sensor sends a signal to the controller.

Electromagnet turns on

The controller closes the circuit. Current flows through the coil and creates a magnetic field.

Valve opens

The electromagnet attracts the iron plunger upward, compressing the spring and lifting the valve plate.

Water flows

Water passes through the open gap and exits through the shower head.

Valve closes

When the person leaves, the circuit opens. The magnetic field disappears and the spring pushes the valve closed.

Review of the original explanation

The basic idea is workable, but the electromagnet should not “lift the magnet.” The powered coil creates a magnetic field that attracts a separate iron plunger or armature connected to the valve.

Physics correction: the motion sensor supplies a control signal; the controller switches current through the coil. A return spring is needed so the valve reliably closes when the power turns off.