Considerations for Power Distribution Units for Artificial Intelligence / GPU-Based Applications

AI queries require 10x the electricity of traditional Google queries.

Source: 2024 EPRI Energy Power Research Institute

As a leader in power management solutions, CPI is at the forefront of these advancements. Our eConnect® intelligent PDUs, designed to meet the rigorous demands of modern data centers now offer the widest range of high-power configurations for high-density needs.  

In this blog, we’ll explore several considerations selecting the right high-power PDU.

Read Also: What is a High Power PDU: Features and Selection Tips

Input Power Selection

In recent years, the most commonly used high- power circuit was either 208V 3PH 60A that provided 17.2kW of power capacity or 240/415V 32A circuit that provided 17.2kW pf power in North America and 23kW internationally. While very high-power densities can be met by dropping multiple such circuits into a cabinet, this is not the optimal solution.

To support very high-power densities, consider the following new circuits:

In the table above, you can see that a 240/415V circuit provides significantly higher power compared to a similar amperage 208V 3PH circuit.

Another advantage of choosing a 240/415V circuit is that all branch circuits are Line to Neutral (L-N) circuits, requiring only single pole breakers. In contrast, 208V circuits require L-L circuits to the loads requiring double-pole breakers. Single pole breakers occupy less space within the PDU, allowing them to maintain an optimal form factor.

The PDUs can be equipped with either an input cord or an AC terminal block. A corded unit offers a plug and play solution that reduces time of deployment. The AC Terminal Block requires an electrician for wiring but minimizes the cost and space associated with the higher amperage pin and sleeve input plugs. If a corded unit is chosen, it is important that only the optimal cord length is chosen to minimize the space and airflow obstructions that could be caused by thick high-amperage cords.

CPI's eConnect intelligent PDUs include 208V 100A; 240/415V 60A and 240/415V 100A configurations. Both corded and hardwired configurations with an AC Terminal Block are available to meet your specific needs.

Branch Circuit Selection

Traditionally, the most common branch circuit breakers on rack PDUs were rated 20A in North America and 16A internationally, both supporting a maximum current of 16A.

GPU-based equipment typically draws 10 – 15A current and a 20A branch circuit breaker provides minimal flexibility in handling minor overloads or to plug multiple devices on the same branch circuit. A 30A rated breaker, with a maximum current capacity of 24A, allows for multiple pieces of equipment to be plugged in.

In the table below, you can see that 30A breakers also help meet capacity requirements with fewer breakers, allowing PDUs with higher capacity requirements to maintain a smaller form factor.

Outlet Selection

GPU-based servers for AI applications usually have multiple power supplies that use 16A-rated C20 connectors, requiring a C19 outlet on the PDU. Therefore, PDUs used for such applications should offer a high number of C19 receptacles, evenly distributed across all available branch circuits on the PDU.

Other Considerations for Purchasing a High-Power PDU

In addition to choosing a high-power PDU that delivers sufficient wattage and has the right number and type of outlets for your devices, other important factors include:

• Locking Outlets: In high-density environments, the risk of human error increases, emphasizing the importance of safety features in the PDU design. Locking mechanism for the C13 and C19 receptacles that work with standard power cords should be considered to ensure inadvertent errors while minimizing additional costs.
• ​Field-Replaceable Controller Module: Ensures continuous operations of the load if intelligence within the unit is compromised. Configuration data held within the controller modules should be easily transferable.
• Secure Array capability: Minimizes number of IP addresses required to maintain the complete PDU infrastructure while providing a continued communication path in the event connectivity within the array is lost.
• Management with DCIM: Check if the PDU can integrate with your existing data center management systems and environmental monitoring for centralized monitoring and control. DCIM application should be capable of making mass configuration changes to the PDU.
• Environmental Monitoring: Additionally, consider if the PDU offers environmental monitoring capabilities, such as temperature and humidity sensors, to provide comprehensive oversight of your data center conditions.
• Space Constraints: Consider the physical size and form factor of the PDU to ensure it fits within your data center layout and rack space constraints.
• Compliance and Certification: Verify that the PDU meets relevant industry standards and certifications for safety, reliability, and environmental sustainability
• Pre-installation within cabinets: High power PDU’s utilize cords with significant bend radius. When used along with direct-to-chip liquid cooling, organization of all equipment within the cabinet takes utmost importance. Pre-installation ensures a seamless turnkey solution is received that minimizes deployment time and risks.

Introducing Chatsworth Products’ High-Power Configurations for eConnect® PDUs

CPI’s eConnect intelligent PDU product line now includes a wide range of high-power configurations.

Whether you require basic functionality or advanced features like switched pro, our intelligent PDU models will support your high-density needs.

• Capacities ranging from 28.8kW to 57.5kW per PDU

• Over 100 high-power configurations

• Enhanced safety and flexibility: Equipped with a 30 amp brand circuit breaker that allows for more devices to be connected to a single PDU without overloading the circuit and flexibility in setup.

• Sustainability: Designed with sustainability in mind, these PDUs ensure equipment longevity and peak performance. Advanced performance monitoring eliminates ghost servers, enhancing overall energy efficiency.

• Customization and Integration: Can be seamlessly integrated into cabinets, with a high degree of customization, simplifying vendor management and deployment. eConnect PDUs provide flexibility when it comes to input power, offering input plugs, unterminated cables, or terminal blocks. Multiple color options and customizable colors help ensure proper load balancing and redundancy.

• Other features include:

  • PDU linking or IP consolidation up to 32 PDUs
  • Input line and outlet amperage on local display and web interface
  • Back-up master PDU for daisy chaining
  • ​Smart daisy chaining sorting

Get started with our free PDU Selector Tool

PDU selection is made easy with CPI’s Power Selector, a free and easy-to-use online software that assists you in selecting the best power product for your application based on your requirements. After you’re done comparing, you can email or print the results.

Need something specific? Get in touch with our team today.