Unique-Bargains 2-Set Magnetic Reed Switch NO NC Door Window Alarm

Magnetic Reed Switch for Alarm Systems

This set includes two magnetic reed switches designed for door and window security monitoring. Each unit operates as a normally open or normally closed circuit that activates when a magnet comes within range. The switches are constructed from white ABS plastic and mount with screws for a secure fit. They suit homeowners or small-business operators adding basic intrusion detection to an existing alarm panel.

Upgrading from Basic Contact Sensors

These switches replace simple mechanical contacts that can wear out or misalign over time. The magnetic operation eliminates physical friction, so the circuit stays reliable through repeated opening and closing cycles. The change is worth it when an older sensor starts giving false alarms or fails to register a closed door. No external power source is needed for the switch itself, simplifying the swap.

Check Wiring and Gap Before Installing

Verify that your alarm panel accepts a dry contact input compatible with a 0-100 V switching range. The magnet must sit 3-15 mm from the switch body to trigger reliably, so measure the door or window gap before mounting. Ensure the frame material allows screw fixing and that the wiring run can reach the panel without splicing. Buyers who need wireless transmission or smart-home integration should look elsewhere.