• Normally Closed (NC) Magnetic Contact
• Designed for Alarm & Security Systems
• Durable ABS Plastic Housing
• Reliable Magnetic Detection
• Surface Mount Easy Installation
• Compatible with Most Alarm Panels
The DH-31 Door Contact (NC) is a magnetic sensor used in security and alarm systems to detect whether a door or window is open or closed.
It consists of two parts: a reed switch sensor and a magnet. When the door is closed, the magnet keeps the circuit closed. When the door opens, the magnetic field is interrupted and the circuit opens, triggering the alarm system.
The DH-31 contact is widely used in home security systems, burglar alarms, access control systems, and commercial security installations.
Its compact design and strong ABS casing make it suitable for installation on wooden, metal, or aluminum doors and windows.
Product Type: Magnetic Door Contact Sensor
Model: DH-31
Contact Type: NC (Normally Closed)
Operating Voltage: Up to 100V DC/AC
Max Switching Current: 0.5A
Max Power Load: 10W
Operating Gap: 15–25 mm
Material: ABS Plastic
Connection Type: Wired (2 Wire)
Installation Type: Surface Mount
Usage: Indoor
Application: Alarm & Security Systems
Home Security Systems
Burglar Alarm Systems
Access Control Systems
Office Doors
Windows Security
Warehouses
Commercial Buildings
Smart Alarm Installations
Q1: What does NC mean in door contact?
NC means Normally Closed – the circuit is closed when the magnet is near the sensor.
Q2: How does the door contact work?
When the door opens and the magnet moves away, the circuit breaks and triggers the alarm.
Q3: Can it be used on windows?
Yes, it works on both doors and windows.
Q4: Is it compatible with alarm systems?
Yes, it works with most wired alarm and security systems.
Q5: Is it easy to install?
Yes, it installs easily with screws on the door and frame.
&url=https://zzmarts.com/product/fire-emergency-break-glass-switch-nc-no-resettable-non-resettable/&media=https://zzmarts.com/wp-content/uploads/2026/01/2025_03_03_17_47_IMG_2833-768x1024.png){kind=link}
Reviews
There are no reviews yet.