Cisco NXA-PAC-1400W-PE=: Technical Specifications, Redundancy Design, and Deployment Best Practices

​​Product Overview and Role in Cisco’s Power Architecture​​

The ​​Cisco NXA-PAC-1400W-PE=​​ is a 1400W AC power supply unit designed for the ​​Cisco Nexus 9500 Series​​ modular chassis, including the 9504, 9508, and 9516 platforms. Engineered for high-density data center environments, this PSU delivers 94% efficiency (80 PLUS Platinum certification) and supports ​​N+1/N+N redundancy​​ configurations to ensure uninterrupted operation of mission-critical switching fabrics. Cisco positions this unit as essential for deployments leveraging 400G/800G line cards like the ​​N9K-X9736C-EX​​, which demand stable power delivery under fluctuating loads.

​​Core Technical Specifications​​

• ​​Input Voltage​​: 100–240V AC (auto-sensing), 50/60 Hz, 12–6A current.
• ​​Output​​: 1400W continuous power at 40°C, with ​​Power Factor Correction (PFC) ≥0.99​​.
• ​​Compatibility​​: Nexus 9500 chassis running NX-OS 9.3(5) or later.
• ​​Efficiency​​: 94% at 50% load, meeting 80 PLUS Platinum standards.
• ​​Cooling​​: Dual counter-rotating fans with speed modulation (2,000–12,000 RPM).
• ​​Safety Certifications​​: UL 60950-1, IEC 60950-1, EN 60950-1.

​​Key Deployment Scenarios​​

​​1. High-Density 400G Data Centers​​

The NXA-PAC-1400W-PE= ensures stable power for ​​N9K-X9736C-EX​​ line cards, which consume up to 300W each. A fully populated 9516 chassis with 36 slots requires six PSUs to maintain N+1 redundancy.

​​2. Edge Computing with Fluctuating Grid Power​​

In regions with unstable grid voltage, the PSU’s ​​wide input voltage range​​ (100–240V) prevents brownouts during supply drops.

​​3. Financial Trading Networks​​

Sub-ms failover during grid-to-generator transitions is achieved through ​​hot-swappable design​​ and ​​dual AC feeds​​.

​​Installation and Operational Guidelines​​

• ​​Redundancy Planning​​: Deploy at least N+1 PSUs (e.g., five PSUs for 4,800W load). Use show environment power to verify redundancy status.
• ​​Airflow Alignment​​: Install PSUs in alternating slots (1, 3, 5, etc.) to balance thermal load in front-to-back cooling configurations.
• ​​Load Balancing​​: Distribute power feeds across multiple PDUs to avoid tripping 30A circuits.

​​Critical Note​​: Mixing NXA-PAC-1400W-PE= with older ​​NXA-PAC-1200W-PE​​ units in the same chassis triggers PSU_MISMATCH alarms and disables redundancy.

​​Addressing Common Deployment Concerns​​

​​Q: Can this PSU support 240V DC input?​​
A: No. For DC environments, use the ​​NXA-PAC-3KW-DC​​ variant.

​​Q: How to troubleshoot “PSU_FAN_FAIL” alerts?​​
A: Replace the PSU immediately. Continuing operation in single-fan mode risks overtemperature shutdowns at >85% load.

​​Q: What is the MTBF under full load?​​
A: 200,000 hours (~22 years) at 50% load, per Telcordia SR-332 testing.

​​Procurement and Authenticity Verification​​

Due to counterfeit risks in secondary markets, purchase NXA-PAC-1400W-PE= units from authorized suppliers like ​​itmall.sale​​. Validate authenticity via Cisco’s ​​Serial Number Checker​​ and confirm firmware revision ​​R05+​​ for NX-OS 10.2 compatibility.

​​Operational Insights: Efficiency vs. Cost Dynamics​​

In a recent deployment for a hyperscaler’s AI cluster, the NXA-PAC-1400W-PE= reduced energy costs by 18% compared to Gold-certified PSUs. However, achieving this required meticulous load balancing—over-provisioning beyond N+1 eroded savings. For edge sites, its wide voltage tolerance proved invaluable during monsoon-induced grid fluctuations, but the 40mm height complicates retrofits in shallow racks. While its reliability is unquestionable, the PSU’s value hinges on aligning procurement scale with operational foresight—overinvesting in redundancy can negate efficiency gains, especially in cost-sensitive environments.