The main way to take a measure of power consumption is directly from the power distribution strip.
It is possible to measure at both a strip and socket level, however the underlying technology in the strip for each type of measurement is different, and the more granular you want your measurement, the more expensive it gets.
“When you measure at a power strip level you only need one or two current transformers to measure the power,” said Rittal’s Mark Roberts.
“If you want to measure at the socket level then you need a current transformer for each individual socket, so the technology required grows with the granularity.”
Ballpark figures for power strip-level measurement hover around $800-$900 per strip, Roberts said. Go down to the socket level and it jumps to $1400 or $1500.
A large data centre packing 500 racks would need approximately twice that number of strips, each of which might contain eight or 10 sockets.
“For that sized centre it could cost about $1 million to monitor at an individual socket level,” said Roberts.
Raritan’s Gary Hull agrees that intelligent systems are the answer, but at the PDU level.
“What Raritan has done is provided the market with an intelligent PDU that measures, meters and switches power by node or infrastructure device,” said Hull.
“This provides a great opportunity for partners to offer proactive power management solutions that augment our [traditional] infrastructure management systems.”
The company also has open source software called Power IQ that can consolidate active power information derived from multiple PDUs at the node level.
Hull said it works with any device that is both SNMP-enabled and can event forward management information base (MIB) files to Power IQ.
Other vendors have similar software offerings, including Eaton and APC.
Like Power IQ, both of these solutions also plug into other third-party management systems such as IBM’s Tivoli.
Eaton is also selling intelligent monitoring primarily at the PDU level.
“We have products that can be retrofitted to ‘dumb’ PDUs so that metering or monitoring capabilities can be added to existing sites quite easily,” said Eaton’s Ciaran Bolton.
Both Eaton and APC are also proponents of taking a modular approach to UPS infrastructure.
Adaptec, meanwhile, provides a way for IT managers to start saving at the equipment level. The company has created a firmware enhancement for its Series 2 and 5 RAID cards that enables IT managers to either spin down or slow down attached drives to a low-power state or complete hibernation to save energy.
“Traditionally there were specific appliances to do this,” said Neil Cameron, field application engineer at Adaptec.
“Our product is for the generic market from workstations upwards. People can simply turn on these new features.”
Feature: How to cut energy costs at the node
By Ry Crozier on Oct 30, 2008 12:37PM