Overview of the A9K-DC-PEM-V3

The Cisco A9K-DC-PEM-V3 is a ​​third-generation DC power entry module​​ designed for Cisco ASR 9000 Series routers, optimized for high-density 400G/800G deployments in data centers and telecom core networks. It replaces legacy V2 models with ​​96% power efficiency​​ and support for ​​-48VDC to -60VDC​​ input ranges, addressing hyperscale demands while maintaining backward compatibility with ASR 9904/9910/9922 chassis.

Technical Advancements Over Previous Generations

• ​​Power Capacity​​: Delivers ​​12kW per chassis​​ (2x6kW modules) with N+N redundancy, doubling the V2’s 6kW limit.
• ​​Adaptive Load Sharing​​: Implements ​​predictive current balancing​​ to prevent single-point failures, reducing voltage drops by ​​18%​​ during peak loads.
• ​​Thermal Efficiency​​: Integrates variable-speed fans with ​​AI-driven airflow optimization​​, cutting heat dissipation by 25% compared to V2.
• ​​Compatibility​​: Supports hybrid deployments with AC-powered modules via cross-fabric power sharing (requires IOS XR 7.9.1+).

Addressing Critical User Concerns

​​Q: Can it coexist with older A9K-DC-PEM-V2 modules in the same chassis?​​
No. The V3’s ​​dual-bus architecture​​ conflicts with V2’s single-bus design. Mixed deployments require dedicated chassis or partition-mode operation.

​​Q: How does it handle 400G line card power spikes during failovers?​​
The module employs ​​dynamic power capping​​ to prioritize critical components, maintaining <2ms voltage stability for optics during N+1 switchovers.

Key Deployment Scenarios

• ​​5G Core Networks​​: Powers energy-intensive 800G modules (e.g., A9K-8X100GE-FC) in metro aggregation nodes requiring ​​99.9999% uptime​​.
• ​​Hyperscale DCI​​: Enables ​​48VDC direct battery plant integration​​, bypassing AC/DC conversion losses for cross-data-center 400G links.
• ​​Financial Trading Hubs​​: Combines with ASR 9000’s ​​<1μs timestamping​​ to ensure uninterrupted low-latency transactions during grid fluctuations.

Implementation and Sourcing

For operators modernizing DC-powered infrastructures, the “A9K-DC-PEM-V3” is available here. Validate chassis compatibility using Cisco’s ​​Power Calculator Tool​​ and ensure firmware upgrades to IOS XR 7.9.1+ for AI-driven load management.

Final Perspective: The DC Renaissance in High-Power Networks

While 800G migrations push operators toward higher-voltage solutions, the A9K-DC-PEM-V3’s ​​-60VDC support​​ positions it as a transitional workhorse for ASR 9000 environments. Its true innovation lies in ​​asymmetric redundancy​​ – allowing one PEM to handle 75% of total load during failures, unlike traditional 50/50 splits. However, organizations planning full 800G fabric overhauls should evaluate newer platforms with native 100VDC support, as the V3’s 12kW ceiling may constrain future density requirements. For brownfield ASR deployments, this module remains the most cost-effective path to 400G readiness without chassis replacement.