Data center architects consider current and future power requirements so they can design data centers that aren’t under- or over-powered. The use of too much power is expensive and wasteful, while the use of too little power can lead to damaging power surges when workloads spike. This is one reason why redundant power, including uninterruptible power supply (UPS) systems, cooling systems and backup generators are data center fundamentals. You know another reason: downtime is devastating.
Let’s explore data center power, including power basics and data center redundancy models and how they relate to the uptime standards associated with data center tiers.
Typically, data centers are set up with several power flow elements: a power source such as a generator, UPS, power distribution unit (PDU), power panel and power whips. Depending on the size of a data center, the power flow may require more than one of the elements.
Power whips connect a data center’s power panel and equipment power cords to help distribute power evenly and improve power usage effectiveness (PUE).
Single-phase power is called “residential voltage” because it is used in residential situations and sometimes in businesses with small workloads. Three-phase power is used in most businesses, industrial operations and data centers that have large workloads and low tolerance for downtime. Three-phase systems enable organizations to optimize PUE and uptime. A three-phase circuit provides greater power density than one-phase at the same amperage, keeping wiring size and costs lower. In addition, three-phase power makes it easier to balance loads and optimizes the utilization of electrical capacity for increase power efficiency. 2
A phase refers to the electrical current (voltage) that passes through a neutral wire. The neutral wire and a phase (live) wire deliver the power. Single-phase systems can deliver up to 230 volts of alternating current and up to 250 watts, but the amount of power varies, so delivery is inconsistent and may result in flickering lights or brief outages. Three-phase systems use three wires (or four if a neutral wire is used) and alternating currents to generate 415 volts. Unlike the single-phase systems, the power output in three-phase systems is continuous and consistent.
As an aside, keep in mind that direct-current (or DC power) is preferred to alternating-current (or AC power) in data centers to eliminate power conversion steps and losses, reduce cooling requirements and support equipment density.
Redundant power systems minimize the risk of unplanned downtime and, in turn, the negative consequences. In data centers, key redundancy components are:
The industry has standardized on certain redundancy levels that are a useful guide to understanding how an on-premises or colocation data center is designed.
Data center classification tiers describe the infrastructure and redundant power components. Let’s say you’re evaluating colocation providers. Your business requirements related to risk tolerance and cost are top factors in deciding which tier is right for your organization. The tiers, according to Hewlett-Packard Enterprise, are:
On-premises and colocation data centers require reliable uninterrupted power. Surprise outages can be disruptive and expensive. According to the Uptime Institute 3:
Want to explore a data center and its infrastructure? Book a tour and bring your questions about power requirements. And learn more about uptime and things to think about related to data center tiers in this CoreSite blog.
1. Understanding the Benefits of Three-Phase Power Distribution
2. Eaton, Power Distribution Handbook
3. Uptime Institute, 2022 Outage Analysis
The CoreSite Team
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