System Sensor MDL3R SpectrAlert Advance Sync-Circuit Module 12/24V, Red

For reliable, code-compliant notification appliance synchronization, the System Sensor MDL3R Sync-Circuit Module delivers a practical, time-saving solution for fire alarm, security and monitoring projects. This SpectrAlert Advance sync module synchronizes strobe flash timing at 1 Hz and aligns horns and chimes to the Temporal-3 pattern, ensuring consistent occupant notification across notification appliance circuits (NACs). With patented two-wire operation, the MDL3R reduces installation complexity by enabling horn/chime silencing on horn/strobe and chime/strobe models while leaving strobes active — a key benefit for staged alerts and maintenance. The module supports two 3 A Style Y (Class B) circuits or one 3 A Style Z (Class A) circuit and can be interconnected to expand synchronization across multiple zones. Housed in a red 5.2" x 5.2" enclosure and backed by a 3-year limited warranty, the MDL3R is built for dependable integration into fire alarm, security and surveillance systems. Ideal for contractors and facilities managers working on commercial, institutional or industrial sites — specify the MDL3R to streamline NAC synchronization and improve notification reliability.

• Simplifies wiring and installation by synchronizing strobes and horns over a two-wire NAC, reducing labor and material costs
• Enables code-compliant notifications by synchronizing strobes at 1 Hz and horns/chimes to Temporal-3 for reliable fire alarm signaling
• Allows selective horn/chime silencing while keeping strobes active, improving occupant notification strategies during staged events
• Flexible zone support: powers two 3 A Style Y (Class B) circuits or one 3 A Style Z (Class A) circuit, and links multiple modules for larger installations
• Compact, red enclosure with 3-year limited warranty ensures easy integration and long-term reliability for security and monitoring systems