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We're trying to select the best UPS within our budget.

Our goal is to allow 2 x HP Proliant ML350 G6 servers time enough to shutdown. We're estimating this to be no more than 10 minutes.

Can anyone help me to understand what I should be looking for in a UPS? Our usual suppliers have quoted us for some fairly expensive gear:

APC Smart UPS 3000 RM XL

.. coming in at close to £2000.

Previously on our old servers we had some APC units that, I believe, were purchased for a few hundred pounds. These were SBS 2003 machines running on Proliant g3's, I think.

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You pay a premium for APC. You may want to check out other brands for cost savings. I don't have as much experience with other brands but I certainly have had problems with APC. I love the irony that the very device that is intended to keep your server up can wind up taking it down. – PHLiGHT Mar 18 '13 at 19:35
That's why I like Tripplite much better than APC. – Alex Mar 19 '13 at 18:00
up vote 2 down vote accepted

I would recommend the APC SUA2200XL and SUA3000XL convertible models if you care about runtime. Both have a package available with the network interface and monitoring card available.

Play with the sizing charts to gauge runtime under your real server loads. The HP ProLiant ML350 G6 power requirements are here. The sizing recommendation is a little over 500VA per system, but assume that the server will run in far less.

They don't fit neatly in racks, but they're a good buy if you don't mind having them external to the enclosure.

In generic terms, I used to use 1400VA units for single servers and 2200VA and 3000vA for multiple. Any will work for your purpose.

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Thanks, this is very helpful – pierre Mar 18 '13 at 18:00
It really depends on what power supply you have in your servers by the way. For the 750W one, ewwhite's suggestion is right on target. But if you have the smaller 460W one you will be able to get a much smaller UPS like the SMT1500I will give you a little shy of 15 minutes per servers to shutdown. – Alex Mar 18 '13 at 19:00
Watch out when you start getting into the 3000VA UPS units as you'll likely need to bring in a higher amp line with a different NEMA connecter (at least in the US). – PHLiGHT Mar 18 '13 at 19:38

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