Siemens (Pyro) PAD-4-9A

Siemens PAD‑4‑9A 9 Amp NAC Expander Kit

The Siemens PAD‑4‑9A is a complete distributed power supply and notification appliance circuit (NAC) expander, designed to supplement Siemens fire alarm control panels by providing additional 24 V DC power for horns, strobes, and other evacuation devices. With its robust power capacity and fault-tolerant design, it’s ideal for large installations or where extended notification coverage is required. 

Key Features:

• High Power Output: Delivers up to 9 A @ 24 VDC for powering NAC wiring and devices. 

• Expanded Circuits: Provides four Class B NAC outputs standard, expandable to four Class A circuits using the optional PAD‑4‑CLSA module. 

• Auxiliary Power Output: Offers 3 A auxiliary 24 VDC output for powering door holders or other auxiliary devices. 

• Isolated Inputs: Two optically isolated NAC inputs from the FACP allow class switching, trouble reporting, and supervisory functionality. 

• Integrated Supervision: Monitors AC power, battery charger status, ground fault, output circuit trouble, and reports via Form C trouble contacts. 

• Strobe Synchronization: Optional synchronization support ensures uniform flash patterns when adding sync modules. 

• Reliable Enclosure: Packaged in a red metal enclosure capable of housing the main board, power supply, and batteries up to 7 Ah or larger with optional kits. 

• Seismically Rated: Complies with seismic standards including OSHPD and IBC/IBC-related certifications. 

Technical Specifications:

• Power Capacity: 9 A total NAC output; up to 6 A with FP2011-U1 or full 9 A with FP2012-U1 power supply 

• Auxiliary Power: 3 A @ 24 VDC

• Inputs: Two NAC inputs, optically isolated

• Supervisory Outputs: Form C trouble relays for general fault and AC fail

• Dimensions: Enclosure typically ~24.5″ × 13″ × 16.5″, weight around 21 lbs for full kit 

The PAD‑4‑9A kit includes main board, power supply (300 W), chassis, and enclosure board, offering a comprehensive solution to upgrade fire systems with expanded NAC capacity and reliable supervision.