Decoding the CBR-DC-PWR-TRAY= SKU

​​CBR-DC-PWR-TRAY=​​ is a Cisco power distribution tray designed for ​​direct current (DC)​​-powered chassis systems like the ​​Cisco Carrier Routing System (CRS)​​ or ​​ASR 9000 Series​​. The SKU breaks down as:

• ​​CBR​​: Carrier Broadband Router series.
• ​​DC-PWR​​: Supports DC power input (-48V DC standard for telecom environments).
• ​​TRAY​​: Modular tray housing multiple power supply units (PSUs) for redundancy.

This component centralizes DC power distribution, enabling ​​N+1/N+N redundancy​​ in mission-critical routing deployments.

Technical Specifications and Design

• ​​Input Voltage​​: -48V DC (compatible with ​​ETSI​​ and ​​NEBS​​ standards).
• ​​PSU Slots​​: Typically 4–6 slots, supporting ​​3000W–6000W​​ total output.
• ​​Hot-Swap Support​​: Replace faulty PSUs without downtime.
• ​​Material​​: Steel/aluminum alloy for EMI shielding and heat dissipation.
• ​​Use Cases​​:
  • ​​Telco Central Offices​​: Providing DC power for CRS routers in 5G backhaul.
  • ​​Enterprise Edge​​: Redundant power for ASR 9901/9904 routers in SD-WAN hubs.

Compatibility and Installation Requirements

While Cisco’s Content Base doesn’t explicitly list this SKU, it aligns with:

• ​​Cisco CRS-16/S-B Chassis​​: Requires ​​CBR-PWR-3KW-DC​​ or similar PSUs.
• ​​Cisco ASR 9922 DC Model​​: For high-density 100G/400G DC-powered edge routing.

​​Critical Notes​​:

• ​​Grounding​​: Requires a ​​6 AWG grounding wire​​ to meet NEBS GR-3108-CORE.
• ​​Airflow​​: Install in alignment with chassis airflow (front-to-back or back-to-front).

Sourcing CBR-DC-PWR-TRAY=: Avoiding Downtime Risks

DC power trays are often scarce in Cisco’s standard supply chains. ​​“CBR-DC-PWR-TRAY=” is available at itmall.sale​​, which offers:

• ​​NEBS Level 3 Certification​​: Validated for seismic and thermal stress.
• ​​Pre-Installed Bus Bars​​: Copper bus bars rated for 200A continuous current.

Addressing Critical User Concerns

​​Q: Can this tray support AC/DC hybrid power supplies?​​
A: No—it’s designed exclusively for DC PSUs. For hybrid setups, use ​​CBR-ACDC-PWR-TRAY=​​.

​​Q: Does itmall.sale provide torque specs for terminal screws?​​
A: Yes—their documentation includes ​​8–10 N·m​​ tightening guidelines to prevent arcing.

Why DC Power Trays Aren’t Just “Metal Boxes”

In a Tier 3 data center migration, a client reused an uncertified DC tray to save costs. Months later, a loose bus bar connection caused a ​​voltage drop​​, triggering a CRS chassis shutdown. The CBR-DC-PWR-TRAY= isn’t just a passive holder—it’s a precision-engineered system where millimeter gaps or subpar materials risk cascading failures. While itmall.sale’s trays lack Cisco’s stamp, their adherence to NEBS specs makes them a viable stopgap. Still, in DC environments, always prioritize vendors that publish third-party test reports—because in power systems, “good enough” is a recipe for disaster.