PDUs come in all types of sizes and flavors – from horizontal rack-mounted PDUs and vertical PDUs, to various types of outlets, input and outlet voltages, and amount of power delivered (i.e., capacity). Depending on your location, the voltages will vary—208V is used for North America only while 230V is used elsewhere. The type of input plugs and outlets will vary as well. And the amount of capacity you need will also dictate which PDU you choose. If your capacity is 5.7kW, you’d better choose a PDU capable of delivering it.
PDUs also come in single phase and either Delta or Wye three phase power. Without delving too much into the technical aspects, single phase power uses one voltage delivered over two hot wires and one neutral and is used primarily for homes. Three phase power consists of three AC voltages delivered over three hot wires—Delta having three hot and one ground and Wye having three hot, one neutral and one ground. Three phase Wye offers the benefit of providing both 208V and 120V and can be used to power both 3-phase and single-phase devices.
There is however another aspect to consider when selecting a PDU—intelligence. PDUs can be very basic with zero intelligence so really all they do is distribute power. Basic PDUs are reliable and lower cost, and sometimes they may be all you need. However, in today’s data centers where power usage effectiveness (PUE) is a critical metric to ensuring efficiency by measuring the ratio of energy used by the data center versus the actual energy delivered to the equipment, you might need a little bit more. Maybe you want to really get into monitoring power usage of individual pieces of equipment, or you need a way to restart or shut down equipment remotely. Or maybe you want to see power usage trends over time to help make informed decisions for improving PUE.
If any of this sounds like something you could use in your data center (or for that equipment you’ve got housed in someone else’s data center), you need an intelligent PDU. Let’s take a closer look at your options.
Metered PDUs – That Little Something More
If all you really want to know is how much power is being consumed by a single PDU, maybe you only need a little bit of intelligence. As a cost-effective option for getting more intelligence than your basic PDU, metered PDUs will show you real-time power data—typically via an LED display right on the PDU itself.
Monitored PDUs – When You Can’t Be There
One step up in intelligence from the metered PDU is the monitored PDU. It too will let you know real-time power usage, but it will also let you see this information remotely using an Ethernet port capable of delivering that data to wherever you are. That means you can also save this data to keep track of trends. Some monitored PDUs will also give you the capability of setting alarms so that you’re notified the minute your power usage hits a certain user-defined level. They may also include ports for connecting sensors that can collect other information from the cabinet, like temperature and humidity sensors for example.
Smart PDUs – When Individual Power Usage Matters
While monitored PDUs will give you power usage information remotely, the smart PDU takes that capability down to the individual outlet level. That way you’ll know exactly which piece of equipment is using the most power (or the least). And once you get to the outlet level, there are other benefits such as being able to configure outlets into groups (hmmm… let’s use these 12 outlets for primary email server power and these other 12 for something else).
Switched PDUs – When Remote Control Matters Most
While the ability to see power usage at the outlet level is great for seeing which piece of equipment is using the most power, sometimes power usage at the cabinet level is all you need. And maybe actually controlling the outlets so you can remotely restart or shut down a piece equipment is more important. If so, the switched PDU is for you.
Managed – When You Want It All
There are those of us that need (or simply want) it all—the ability to measure power usage for each outlet AND the ability to shut down individual pieces of equipment remotely, as well as all the other benefits that go along with an intelligent PDU. A fully managed PDU will offer this highest level of outlet-level control and monitoring.
The good news is that Siemon offers a full range of basic, metered and intelligent PDUs in their comprehensive PowerMax™ line so you can get the exact amount of intelligence you need! All PowerMax PDUs feature soldered connections for superior reliability and come with a 3-year warranty.
PowerMax intelligent PDUs—available in monitored, smart, switched and managed—offer an industry leading accuracy of +/-1%, an IP address sharing option, outlet grouping and group access control, and an intuitive user web interface for easy-to-read power usage information and for setting alarm thresholds and group settings.
Click HERE for more information on Siemon’s PowerMax PDUs.