What is a Smart PDU? (And How is it Different from a Basic PDU?)

Types of Smart PDUs

The smart PDUs can be further classified into monitored and switched. At the core, the PDU offers reliable power distribution while more intelligent PDUs add remote monitoring capabilities, energy management, and future proof design platforms.

Monitored PDU

Monitored PDUs provide a comprehensive view of power usage, both at the rack and via remote access while continuing to provide reliable power distribution to critical IT equipment. Monitored PDUs are available in unit-level and outlet-level remote monitoring configuration options, which offer a more granular view of power usage down to the device level. They offer quick access to critical information to evaluate energy usage trends as well as provide alarming capabilities to alert users of breaches in user-defined power thresholds. They are recommended for data centers that want to monitor or improve power usage effectiveness (PUE).

Switched PDU

Switched PDUs provide a comprehensive view of critical IT equipment power usage, both at the rack and via remote access with the added ability to remotely turn on, turn off, or reboot power at each outlet. Switched PDUs are also available with unit-level and outlet-level remote monitoring configuration options. Switched PDUs are ideal for data centers needing to limit power usage at the outlet to avoid accidental overloads as well as remote data centers. They are extremely useful for data centers that require a quick and easy way to power cycle equipment in a large facility or, in some cases, an entire network of facilities. 

Common Features of Smart PDUs

When selecting a smart PDU, these key features should be considered:

IP Aggregation

IP addresses and switch ports are increasingly expensive, so data center managers can reduce the cost of deploying smart PDUs by utilizing units with IP aggregation capabilities. If concerned about deployment costs, it is important to research manufacturer limitations as the number of units that can be aggregated on a single IP address vary from 2 to 50 devices. Other features like IP aggregation with self-configuration of downstream devices can also significantly reduce deployment time and costs.

Environmental Monitoring

IT equipment is susceptible to environmental conditions such as heat and moisture. Smart PDUs can incorporate environmental sensors to proactively monitor environmental conditions within the rack to ensure optimal operating conditions without the need to deploy a separate monitoring solution.


Remote Connectivity

Smart PDUs also provide data center managers with the ability to access the PDU remotely through the network interface or serial connection to monitor power consumption and configure user-defined alert notifications to prevent downtime.

Out-of-Band Communication

If the primary network to the PDU goes down, some PDUs provide redundant communications through integration with out of band management devices, such as serial consoles or KVM switches.

DCIM Access

There are a wide variety of DCIM solutions on the market that can provide users with a single access point to view real-time power and environmental data. DCIM also provides the ability to create and receive trend reports that provide visibility of the entire facility to help data center managers improve efficiency and availability.

Key Considerations When Selecting a Smart PDU

Smart PDUs provide precise monitoring and control of energy consumption. They can give data center managers the information to right-size power infrastructure and eliminate unnecessary expense. Other important considerations when selecting smart PDUs are their abilities to ensure reliability, functionality and adaptability.

Reliability

Smart PDUs while packed with advanced features should not have their core function compromised or impeded. Whether a basic or smart PDU is utilized, it is important to purchase PDUs from a manufacturer focused on quality and reliability. Not all manufacturers do 100% testing of every unit that leaves their facility. It is recommended to identify manufacturers who not only test every single unit, but to find one who goes to great lengths to test the reliability of the unit’s core function over time during product development.

High Temperature Grade
Company efficiency initiatives are resulting in data centers raising the temperature on their thermostat to reduce energy consumption. As a result, data centers are experiencing an increase in facility temperature. This change requires manufacturers to design PDUs to operate in higher temperatures. Depending on the manufacturer, PDU maximum operating temperatures range from 45°C up to 65°C. A high temperature grade PDU should be considered in high temperature environments to ensure reliability and availability in power distribution.

Alternating Outlets
As rack densities increase, cable management and load balancing become a challenge. If loads are not properly balanced across circuits and phases, data center managers risk overloading circuits or stranding power. To simplify circuit/phase balancing and cable management, PDU manufacturers offer color coded alternating outlets that significantly streamline the deployment process.

Locking Outlets
Outlet locking mechanisms secure the physical connection between the IT equipment and the PDU to ensure power cords are not accidently pulled out of the outlet, causing an inadvertent load drop. Globally, the most common standard for outlets used in PDUs are the IEC320 C13 and C19. IEC receptacles are internationally accepted and handle output voltages up to 250V. There are several options ranging from retention to locking outlets available on the market.

Functionality

Smart PDUs can measure, manage and report on the energy usage of data center devices in real-time. With precise levels of metering and management control, data center managers can optimize that energy usage and more easily support equipment and capacity changes. Also with an understanding of the power consumption for each IT device, they can justify purchase of a more updated technology.
 
Using smart PDUs, data center managers can schedule power cycling of unused IT equipment remotely to reduce energy consumption. They can right-size power infrastructure to eliminate unnecessary capital expense, perform charge-backs based on actual amounts of energy consumed, and proactively manage consumption for efficiency.

Smart PDUs can deliver proactive notification of impending issues before they occur. Warning and critical threshold settings once breached can alert users to address critical issues such as smart PDUs experiencing overload conditions that could otherwise trip the breaker and the connected loads. All notifications are received in standard format, such as SMS, SNMP traps or e-mail. Smart PDUs can be integrated with a centralized management software, which will enable them to be easily managed.

Adaptability

Rack-level flexibility is an important factor in helping data centers adapt to constant change, which often means higher densities and the demand for greater efficiency and control.

Future-proof designs in smart PDUs are opted over the previous approach of oversizing infrastructure systems, which is inefficient in terms of capital and energy cost. Data center managers with upgradable basic PDUs and smart PDUs can update their hot-swappable monitoring device easily to leverage new technologies and accommodate changing business needs without having to replace entire power strips or interrupt power to critical servers.