Door contact sensor BLOW 4922# model HO-03C brown magnetic reed switch

Wired door contact sensor BLOW HO-03C in brown is a surface-mounted magnetic reed switch designed to detect opening and closing of doors and windows. The device consists of a compact contact housing and a matching magnet that together form a normally closed magnetic circuit, opening when the magnet is separated from the contact. It is intended for integration with alarm panels, access control systems and simple automation circuits where reliable detection of an entry point state is required.

Advantages

The contact sensor provides a low-profile, discrete appearance in brown finish suitable for many interior surfaces. Its wired connection offers stable signal transmission without the need for batteries, and the magnetic reed switching element ensures long operational life with minimal maintenance. The surface-mounted design simplifies installation on door frames or window sashes and the device is compatible with a wide range of alarm and control systems that accept normally closed contact inputs.

Suitable for

• Residential entry and window monitoring
• Commercial premises access control and intrusion detection
• Integration with alarm panels and wired security systems
• Simple automation tasks that require door/window state feedback

Key specifications

• Operating principle: magnetic reed switch (kontaktron)
• Mounting type: surface-mounted
• Finish / colour: brown
• Connection type: wired contact leads for normally closed circuits
• Typical applications: doors, windows, and other movable panels

How to use

Mount the contact housing on the fixed frame and the magnet on the moving part so that the two elements align and close when the door or window is shut. Connect the wired leads to the alarm panel or control input configured for normally closed contact monitoring. Verify alignment and operation by opening and closing the door or window while observing the control panel's input status. Ensure cable routing is protected from pinch points and secure all components with appropriate screws or adhesive as recommended for the installation surface.

Usage recommendations

Place the sensor and magnet within the manufacturer's recommended gap distance for reliable operation and avoid locations exposed to strong electromagnetic interference or direct moisture. Use the brown finish to match interior fittings and check compatibility with the control panel input type before installation.