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Two white ABS magnetic reed switches with screw mounts

Unique-Bargains

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

SKU CH-43M8-PJN6Y

Two magnetic reed switches with NO/NC contacts trigger alarms when doors or windows open, operating up to 100V with a 15mm sensing gap

  • TypeSurveillance - Home Safety & Security
  • NO/NC switch activates when magnet approaches
  • Reed switch operated by magnetic field
  • Designed for alarm systems on doors and windows
  • Screw-mounted design allows straightforward installation
  • Works at 0-100V with 3-15mm sensing distance

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.

Highlights

  • NO/NC switch activates when magnet approaches
  • Reed switch operated by magnetic field
  • Designed for alarm systems on doors and windows
  • Screw-mounted design allows straightforward installation
  • Works at 0-100V with 3-15mm sensing distance

Specifications

BrandUnique Bargains
TypeSurveillance - Home Safety & Security

Questions about this item

What mounting method and hole pattern does the ABS housing use?

The housing is screw-mounted; drill pilot holes for the two mounting tabs and fasten with wood or drywall screws appropriate for the door or frame material.

How do I wire the NO and NC terminals correctly during installation?

Connect the common lead to your alarm panel input, then choose either the normally-open or normally-closed terminal so the circuit closes when the magnet is within 3-15 mm of the switch.

How often should I check the magnet-to-switch gap and contact reliability?

Inspect the 3-15 mm gap every six months; clean the reed contacts with a dry brush and verify the circuit toggles cleanly when the magnet approaches.

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