Power requirements for Blade Encolusres

[NS_4]

Hi all, what is required to power 3 blade enclosures fully loaded with a mix of bl20p and bl20pG2 using single-phase power (240v), the mini bus bar can support 3 enclosures, however the single-phase power enclosure only has 4 power modules, using the configurator it says that it can support this configuration, however we have been informed by an engineer at hp that this does not work in reality and hp support keep refering to the documentation. Can anyone confirm what the official position is on this?

[NS_4]

Well i've answered my own question on this, the answer is that it depends. When they were initially introduced the power consumption of the blades was significatly lower that it is today mainly due to the increased cpu speeds and this will only increase. Even though the documentation states that a single phase power supply with a maximum of 4 power modules and a mini bus bar can support 3 blade enclosures, the reality is that with the latest blade servers (and this will only get worse) the power demands of the servers soon outstrips what a single phase power enclosure can supply.

[Doug de Werd]

yes you are correct. At the power levels the G2 requires, the only assured configuration that will work is the 3 phase power system.

Thanks,
Doug

[David Claypool]

There's a great utility that will help in your planning. When you're viewing one of the blades' product page, in the left navigation bar under "Solutions" is a link "BL p-Class Sizing Utility" (it actually takes you to a spreadsheet that is a gateway to the actual p-Class one). You can access the spreadsheet for the p-Class directly at: http://h30099.www3.hp.com/configurator/calc/BL%20p-Class.xls

[NS_4]

Doug - i'd have to agree with you on that statement.
David - Yeah i've used it and to be honest it's not that great in fact it is the reason for posting the question, because as soon as a new blade model comes out the power requirements change and a new power sizing guide comes out, which is great if it is a new implementation, but a pain when new blades are being added to an existing implementation and suddenly you wonder why you can't use half a blade enclosure because the new servers can't stick to some predefined power consumption rating (because there isn't one.)