Simplex 4901-9820 Conventional Sounder

Description

The Simplex 4901-9820 TrueAlert Conventional Sounder is a high-performance, non-addressable audible notification appliance engineered to deliver definitive, penetrative emergency signaling across demanding industrial and commercial facility layouts. Featuring a harmonically rich sound signature tailored to pierce high-noise ambient settings, this premium wall-mounted sounder bridges conventional notification design with advanced multi-zone command architecture. Built with an impact-resistant, flame-retardant red thermoplastic cover profile, it serves as a highly reliable, durable asset for institutional protection networks.

Technical Specifications Table

Dual Operational Logic: Standard Free-Run and SmartSync Two-Wire Integration

The standout advantage of the Simplex 4901-9820 Conventional Sounder is its onboard switch-selectable operational logic. When set to standard Free-Run mode, the horn directly monitors the incoming electrical voltage from a conventional Notification Appliance Circuit (NAC). It activates dynamically based on the loop current, tracking panel cadence parameters like Temporal Code 3, March Time patterns, or specialized continuous evacuation signals. This makes it an ideal drop-in solution for direct replacement layouts on conventional legacy circuits.

By toggling the internal selector switch to SmartSync mode, the horn unlocks high-efficiency two-wire system control. This mode allows the sounder to share a single pair of circuit wires with visual strobe units while maintaining independent operation. Under this configuration, the horn can be silenced manually (“on-until-silenced”), while the flashing visual indicators remain active (“on-until-reset”) over the exact same two wires. This two-wire advantage drastically minimizes line configuration costs, conduit weight, and installation labor for both modern building retrofits and new infrastructure footprints.

• High-Impact Structural Housing: Molded from robust, flame-retardant thermoplastic finished in vibrant emergency red with white raised “FIRE” lettering.
• Diode-Polarized Input Circuitry: Features a polarized backend diode array built for direct, reliable wiring supervision over reverse-polarity notification lines.
• Flexible Backbox Compatibility: Flat rear housing contours require zero deep box recessing, adapting cleanly to single-gang, double-gang, or 4-inch square boxes.
• Acoustic Sound Attenuation: Supports the optional 4905-9838 stick-on adhesive sound dampers to safely drop output by 5 to 6 dBA in tight spaces like stairwells or reverberant zones.

Frequently Asked Questions (FAQ)

Q1: What is the primary difference between Free-Run mode and SmartSync mode on this horn?
A: Free-Run tracks conventional panel NAC voltages directly for pulsed or continuous outputs. SmartSync carries both audio commands and synchronized strobe data over a single pair of wires, allowing you to silence the horn while the strobe continues to flash.

Q2: Does this conventional fire alarm sounder require a separate auxiliary power line?
A: No. The 4901-9820 is line-powered, drawing all necessary operational current directly from the 24 VDC signaling circuit of the host fire panel or NAC extender card.

Q3: Can the horn cover color be changed in the field after project installation?
A: Yes. Simplex offers standalone white replacement covers with sharp red “FIRE” lettering (Model 4905-9989), allowing for rapid on-site aesthetics adjustments without discarding the functional horn module.

Q4: Is specialized high-voltage wiring needed to connect this sounder module?
A: No. The device operates on safe low-voltage 24 VDC current loops and features heavy-duty terminal blocks that securely accept standard field wire sizes from 18 AWG down to thick 12 AWG lines.

Q5: What are the decibel output ratings of this horn inside a real building zone?
A: Under standard nominal 24 VDC signaling, the unit generates a clear 96 dBA output inside anechoic rooms, and a verified code-minimum 89 dBA output inside traditional UL 464 reverberant test environments.

Q6: Which central fire alarm consoles natively support the SmartSync two-wire advantage?
A: It integrates seamlessly with intelligent addressable Simplex panel families—including the 4006, 4007ES, 4010ES, and 4100ES series—or through standalone 4905-9938 SmartSync Control Modules.

Q7: Where is this TrueAlert low-current notification peripheral manufactured?
A: This authentic life-safety field sounder component is built to exacting global safety standards and is manufactured in Mexico.