SECO-LARM - SM-431-TQ/W - Surface-Mount Closed Loop Magnetic Contact

Product Overview

The SECO‑LARM SM‑431‑TQ/W is a miniature surface‑mount closed‑loop magnetic contact with an SPST N/O configuration, 1‑inch gap, iridium‑plated reed switch, gold‑plated screw terminals, and a rare‑earth neodymium magnet. UL and cUL listed, white finish, sold in multiples of 10.

Key Configuration

• Loop type: Closed loop
• Electrical configuration: N/O (Normally Open)
• Operating gap: 1" (25mm)
• Contact rating: 1.0A @ 10VDC max, 10W max
• Switch cycles: 50 million (0.1mA @ 5VDC)
• Magnet type: Rare-earth neodymium

Key Features

The SM‑431‑TQ/W is a miniature surface‑mount magnetic contact for door and window position monitoring in security systems. It features an N/O (Normally Open) configuration — the circuit closes when the magnet is present (door closed) and opens when the magnet is removed (door opened), triggering an alarm. The 1‑inch gap accommodates standard installations, with a rare‑earth neodymium magnet ensuring consistent magnetic field strength.

Technical Context

The switch uses an iridium‑plated reed contact with high melting point and Vickers hardness for extended life (50 million cycles) and higher handling power, with gold‑plated screw terminals and a quick‑connect terminal block for reliable corrosion‑resistant wiring. Tape is included to cover screw terminals for added insulation and protection.

Installation Notes

Measure 51 × 10 × 6 mm, housed in a high‑impact ABS plastic case with a white finish (brown also available). The unit operates from -25°C to 70°C, is UL and cUL listed, includes mounting screws and double‑sided tape, has removable mounting tabs, and carries a lifetime limited warranty. Sold in multiples of 10.