Magnetic Door Contact Reed Sensor Switch – NC Wired MC4
Magnetic Door Contact Reed Sensor Switch – NC Wired MC4
Magnetic Door Contact Reed Sensor Switch – Model MC4
Keep your home or business secure with this compact and reliable Magnetic Door Contact Reed Sensor Switch. Designed for easy installation on doors, windows, cabinets, and gates, this wired NC (Normally Closed) reed switch detects opening and closing movements with precision — making it an ideal component for alarm systems, access control setups, and automation projects.
Key Features
- Compact Design: Slim 51 × 10 × 10 mm profile fits flush on most door and window frames without being obtrusive.
- Reliable Reed Switch Technology: Magnetic induction distance of 20–30 mm ensures consistent, accurate detection every time.
- Normally Closed (NC) Mode: Triggers your alarm or automation system the moment the magnetic contact is broken — providing immediate notification.
- Wired Connection: Secure and stable wired lead for dependable signal transmission with no wireless interference.
- Versatile Compatibility: Works with most standard alarm control panels, home automation systems, and DIY security setups.
- Durable Build: Rated at 0.5A / 100V / 10W for long-lasting, stable performance in everyday environments.
Specifications
| Model | MC4 |
| Size | 51 × 10 × 10 mm |
| Current / Voltage | 0.5A / 100V / 10W |
| Induction Distance | 20–30 mm |
| Mode | NC (Normally Closed) |
| Connection Type | Wired |
How It Works
The MC4 Reed Sensor Switch consists of two parts: a magnet and a switch unit. When the door or window is closed, the magnet keeps the reed switch in its Normally Closed (NC) state. As soon as the door or window opens and the magnet moves away, the circuit is broken — triggering your connected alarm or automation system instantly.
Ideal For
- Home and business security alarm systems
- Access control and entry monitoring
- Smart home and automation integration
- Cabinet, gate, and window monitoring
- DIY electronics and maker projects
For more information on home security best practices, visit the U.S. Consumer Product Safety Commission (CPSC) Home Safety Resource.
Frequently Asked Questions
Q: What does "NC" (Normally Closed) mean for this magnetic door reed switch?
A: NC stands for Normally Closed. This means the switch circuit is closed (connected) when the magnet is near the sensor. When the door or window opens and the magnet moves away, the circuit opens (breaks), triggering your alarm or automation system. This is the most common configuration for security sensors.
Q: What types of doors and windows is the MC4 magnetic contact switch compatible with?
A: The MC4 wired magnetic door contact reed switch is compatible with most standard interior and exterior doors, windows, cabinets, and gates. Its slim 51 × 10 × 10 mm form factor makes it easy to mount on wood, metal, or uPVC frames using screws or adhesive.
Q: Can this reed sensor switch be used with existing alarm control panels?
A: Yes. The MC4 wired reed sensor switch is designed to work with most standard alarm control panels and home automation systems that support NC (Normally Closed) wired contact inputs. Simply connect the wired leads to the appropriate zone terminals on your control panel.