LCN SEM7840 689 12V/24V/120V Recessed Wall Mounted Magnetic Door Holder

Keep fire and smoke doors reliably held open during everyday operations while ensuring automatic, fail-safe release during emergencies. The LCN SEM7840 recessed magnetic door holder is an electromagnetic door holder engineered for commercial security and life-safety applications—offering a low-profile recessed installation that preserves aesthetics and resists tampering. With tri-voltage support (12V / 24V / 120V) and a 35 lb holding force, the SEM7840 integrates easily with fire alarm panels, building monitoring, and access control systems to provide dependable door retention without additional power hardware. Constructed with a die-cast housing and UL listing for labeled fire doors, this unit meets industry standards for durability and code compliance. Ideal for hospitals, schools, office buildings, and retail environments where coordinated security, surveillance, and emergency response are essential. Specify the SEM7840 when you need a compact, code-compliant electromagnetic solution—contact sales to confirm compatibility with your fire alarm or order now to enhance your facility’s safety and security.

• Keeps doors securely held during daily use and releases automatically during alarm conditions for reliable life-safety performance
• Low-profile recessed design (SEM7840) provides a clean, tamper-resistant installation ideal for corridors and pocket doors
• Tri-voltage compatibility (12V / 24V / 120V) simplifies integration with existing fire and building management systems
• 35 lb holding force provides dependable retention for labeled fire and smoke barrier doors, reducing accidental closures
• Die-cast housing and UL listing ensure code compliance and long-term durability in commercial, healthcare, and educational facilities
• Fail-safe operation ensures doors can be operated manually under alarm conditions for safe evacuation and monitoring workflows