“Power scares people,” says Richard Brooke, HP Americas Team Lead, Rack and Power. “It’s one thing when you’re dealing with a traditional three-pronged plug, but now that we’re getting into larger blade servers, power distribution units and three phase power circuits, people often don’t know where to start.”
Brooke, along with the rest of the HP Rack and Power field team, is on a mission to educate IT managers about power, from what type of plug to use, to how to size a power distribution unit (PDU), to how to select the correct uninterruptible power supply (UPS).
“We’re going to teach people how to ‘talk plug,’” he says. “It’s like the pieces of a puzzle. Once you get a basic understanding of how it all fits together you’ll stand back and say, ‘What was I afraid of?’”
The first step is proper power planning. To get the most from your HP ProLiant server implementation, says Brooke, figure out how much power you require. Using the analogy of a water pipe, he compares amperage to the size of the pipe, voltage to the water pressure and volt amps (voltage multiplied by amperage, or VA) to the amount of water flowing through the pipe. For example, a configuration of 16 blades using 1.2 amps each, four ProLiant DL360 servers drawing two amps per unit, and a two-amp switch, would have a total power draw of 29.2 amps.
Making good choices
When it comes to sizing a power distribution unit or PDU, there’s no easy ‘one size fits all’ answer. The two main factors to consider are VA capacity, which should match the load of the server enclosure, and the number and type of connectors required, says Brooke.
Part of the process includes educating people about three-phase power circuits, a more efficient way of delivering power to the data center that combines three single line circuits that are delayed from one another (or phase displaced). The goal is to ensure that the data center is using the right type of power with the right type of hardware to distribute it.
“This is where we may have to play mediator between IT and Facilities,” Brooke says. “We’ll say, ‘We want to deploy this many three-phase power distribution units, with this many breaker panels: can we do this?’”
From there, the team may recommend an HP power distribution rack (PDR), designed to deliver power at a server row level using customized, pre-cut cables that take up less space under the floor for greater efficiency. The final steps include selecting the right uninterruptible power supply (UPS) and cooling options.
HP offers an extensive range of UPS products with features like load segment control, hot swap batteries, enhanced battery management, extended run time modules and 60 days advanced notice when batteries need to be replaced. The choice depends on whether you need high-volt or low-volt, single or three-phase power, and how much run time is required, as well as planning for future growth.
For cooling, HP offers several innovative products including the Modular Cooling Unit, an alternative to traditional cooling methods that uses facilities-chilled water to remove heat from the data center in an environmentally friendly and efficient manner.
“We basically go in and talk about common-sense ways to use ProLiant products and deploy them smartly,” says Brooke. “If you don’t, your blade servers could end up as one big data-center paperweight.”