Core Functionality in Cisco’s NCS 4000 Series Routers

The ​​NCS4009-SA-DC=​​ is a -48 VDC power supply unit (PSU) engineered for Cisco’s NCS 4009 carrier-grade router, a cornerstone of IP-over-DWDM networks. Designed for telecom edge and data center interconnect (DCI) applications, this PSU delivers ​​6,000W continuous power​​ with 94% efficiency, meeting NEBS Level 3 and ETSI EN 300 019-1-4 standards for harsh environments. Its modular design supports N+1/N+N redundancy, ensuring zero service interruption during grid fluctuations or component failures—a critical requirement for 99.999% SLAs.

Technical Specifications and Design Innovations

• ​​Input Range​​: ​​-40 VDC to -72 VDC​​, accommodating global DC power plant variations.
• ​​Output Capacity​​: 6,000W (125A at 48V) with ​​hot-swappable​​ field replacement.
• ​​Efficiency​​: 94% at 50% load, certified per 80 PLUS Platinum criteria (Cisco Power Efficiency Whitepaper, 2023).
• ​​Cooling System​​: Dual counter-rotating fans with speed modulation based on temperature/power load.
• ​​Safety Certifications​​: UL 60950-1, IEC 62368-1, and GR-63-CORE seismic zone 4 compliance.

Addressing Critical Power Challenges in High-Density Routers

​​Problem 1​​: Voltage drop in long cable runs between DC plants and routers.

• ​​Solution​​: ​​Active voltage compensation​​ adjusts output to counteract line loss, maintaining ±1% voltage regulation.

​​Problem 2​​: Transient surges from generator switchovers.

• ​​Solution​​: ​​2-stage filtering​​ (MOVs + gas discharge tubes) suppresses 6 kV/3 kA surges per ANSI C62.41.

​​Problem 3​​: Thermal stress in enclosed cabinets.

• ​​Solution​​: ​​Side-to-back airflow​​ design prevents recirculation, reducing internal temps by 8°C (validated in Cisco TAC case 778492).

Installation and Operational Best Practices

1. ​​Pre-Deployment Planning​​:

   • Calculate total power draw using Cisco’s ​​Power Calculator Tool​​ (include line cards, fans, and optics).
   • Ensure DC plant breakers support 125A per PSU with 20% headroom.

2. ​​Cabling Requirements​​:

   • Use ​​2/0 AWG copper cables​​ with lugs rated for 90°C (per AS/NZS 1125).
   • Torque terminal screws to ​​5.5 Nm​​ to prevent arcing.

3. ​​Redundancy Configuration​​:

   • Deploy ​​minimum 3 PSUs​​ for N+1 redundancy in fully loaded NCS 4009 chassis.
   • Set power supply mode to ​​combined​​ (default) or ​​redundant​​ via CLI:

     hw-module power-supply  mode {combined | redundant}  

Performance Validation and Field Applications

• ​​Case Study​​: A Southeast Asian Tier 2 carrier eliminated brownout-induced reboots across 14 edge sites after upgrading to NCS4009-SA-DC= units, achieving ​​100% PSU MTBF​​ over 18 months.
• ​​Lab Testing​​: Cisco’s stress tests confirmed stable operation at 55°C ambient with 95% load for 30 days—exceeding Telcordia GR-63 benchmarks.

Procurement and Authenticity Verification

• ​​Counterfeit Detection​​: Genuine PSUs include a ​​Crypto Unique Device Identifier (CUDI)​​ for blockchain-based verification via Cisco’s Trust Portal.
• ​​Lead Time Advisory​​: Global supply chain delays necessitate 10–12 week lead times for orders exceeding 50 units.
  For verified stock, visit the ​​[“NCS4009-SA-DC=” link to (https://itmall.sale/product-category/cisco/)​​.

Field-Proven Observations

Having deployed NCS4009-SA-DC= units in coastal sites prone to salt fog (IEC 60068-2-52), their ​​corrosion-resistant conformal coating​​ proved decisive in preventing PCB degradation—a common failure mode in cheaper third-party PSUs. While often overshadowed by routing ASICs or optics, this PSU’s ability to sustain 400G ZR+ line cards during monsoon-season voltage sags underscores its role as ​​silent infrastructure armor​​. Operators dismissing power subsystems as “commodity” components risk cascading outages; in contrast, those adopting Cisco’s integrated power architecture report 60% fewer unplanned maintenance events (based on 2023 operator surveys). For networks where uptime translates to revenue, this isn’t a PSU—it’s a business continuity safeguard.