HC31 Door Magnetic Alarm Detector White Normally Closed The HC31 is a compact door magnetic alarm detector designed for reliable door and window contact sensing in security and access control systems. It delivers stable signal output with selectable normally closed or normally open conversion, simple installation options, and compatibility with common alarm and intercom projects. Key benefits Reliable door state detection for perimeter security and access control. Flexible signal output with NC COM conversion to match different control panels. Low profile ABS housing for durable, unobtrusive installation. Simple installation by surface mount technology or screw fixation and standard homogeneous terminal connection. Compact and lightweight for easy integration into retail, industrial, and building systems. Main specifications Model: HC31 Type: Other alarm detectors Communication method: wired Signal output: Normally closed normally open conversion type NC COM Sensing distance: 520 mm or 2025 mm Action distance: 1525 mm Transmission frequency: 315 433 Launch distance: 100 Working temperature: 10 to 50 C Current: 0.5 A Material: ABS Shell color: white brown Installation method: SMT Fixed method: screw installation Connection method: homogeneous terminal Alarm method: consult customer service Unit weight: 0.03 kg (30 g) Package: 10 SET BAG Minimum quantity: 10 Why choose the HC31 Compatibility: Designed for seamless use in shopping mall security systems factory sites building intercom projects and standard alarm systems. Versatility: Selectable NC or NO output and multiple sensing distance options to match door types and installation gaps. Ease of installation: Supports SMT mounting for preassembly and screw fixation for field installation with homogeneous terminal wiring. Durable construction: ABS housing withstands typical indoor environments across a wide working temperature range. Typical applications Retail entry points and emergency exit monitoring in shopping malls to detect unauthorized openings. Factory and warehouse doors for integration with centralized alarm or access control systems. Building intercom and security alarm installations where wired door contact signals are required. Package and ordering Supplied in batches of 10 sets per bag. Minimum quantity 10. For integration details such as alarm wiring configuration and compatible control panel settings consult customer service.