Cisco PWR-3900-AC — Reliable 400W Power for Your 3900 Series Router

Keep your Cisco 3900 Series ISR running with confidence. This refurbished Cisco PWR-3900-AC delivers 400 watts of clean, stable AC power and supports hot-plug installation — so you can add or replace the supply without taking your network offline. Ideal as a primary or redundant (secondary) power source.

Key Specifications

• Part Number: PWR-3900-AC (also referenced as PWR-3900-AC=)
• Power Output: 400 Watts
• Input Voltage: AC 100–240V (auto-sensing, worldwide compatible)
• Frequency: 47–63 Hz
• Form Factor: Hot-plug, plug-in module
• Use: Primary or redundant (secondary) power supply
• Compatibility: Cisco 3925, 3925E, 3945, 3945E Integrated Services Routers

Why Buy from Reef Telecom?

• Industry-leading 10-year warranty on all refurbished equipment
• Free shipping on orders over $300
• Every unit professionally tested and inspected before shipment
• Trusted by IT professionals and enterprises nationwide

Compatibility & Use Cases

The PWR-3900-AC is designed for the Cisco ISR 3900 Series, including the 3925, 3925E, 3945, and 3945E routers. Deploy it as a primary power supply for new installations or as a secondary hot-swap unit for power redundancy in mission-critical environments such as branch offices, data centers, and enterprise WAN deployments.

Free ground shipping on orders over $300. Same-day shipping on orders placed before 4PM EST.

All products include our industry-leading 10 Year Warranty backed by Reef Telecom.