SW-420 Normally Closed Alarm Vibration Sensor Module

The SW-420 Normally Closed Alarm Vibration Sensor Module detects shocks, knocks and vibration with an SW-420 normally closed vibration switch. An LM393 comparator turns the switch signal into a clean digital output, and an on-board potentiometer sets the sensitivity, so it connects straight to an Arduino, ESP32 or alarm circuit.

SW-420 Normally Closed Vibration Sensor Specifications

• Sensor: SW-420 normally closed vibration switch
• Comparator: LM393
• Output: digital (DO), changes state when vibration passes the set threshold
• Sensitivity: adjustable with the on-board potentiometer
• Supply voltage: 3.3–5 V
• Pins: VCC, GND, DO
• Indicators: power LED and output LED

SW-420 Normally Closed Vibration Sensor Applications

• Burglar and anti-theft alarms for doors, windows, bikes and cars
• Knock and tap detection
• Machine vibration and fault monitoring
• Earthquake and shake detection demos
• Arduino and STEM classroom projects

What's in the Box

• 1 × SW-420 vibration sensor module

Tip: Fix the module firmly to the object you want to monitor, then turn the potentiometer slowly until the output LED reacts to a light tap but stays steady at rest. Read DO with an interrupt or a fast loop, because vibration pulses can be very short.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.