Online/double-conversion UPS economy/high efficiency modes?

[mike-nanog at tiedyenetworks.com (Mike)]

On 12/06/2012 12:49 PM, William Herrin wrote:
> Hi folks,
>
> I'm looking at several brands of rackmount 3kva double-conversion
> UPSes, such as Tripp Lite and Eaton Powerware. I'm specifically
> looking for something that will work as a line-interactive UPS until
> the power starts to misbehave and will then switch to
> double-conversion mode until a while after the last power bump.
>

I recently went to the tripplite 16kva online double conversion ups and 
did note the increased ineffeciency. However, the financial cost of that 
ineffeciency doesn't appear to be more than $40 - $60 / mo. So I am 
wondering at your scale with only a 3kva model, really, what is the 
final dollar cost to you versus the effort and dubious benefits of 
writing scripts or depending on embedded logic to do the right thing? 
The whole reason you have online double conversion vs line interactive, 
is to have the best available protection, and when you are on line 
interactive - even if it can switch - you are still taking that risk of 
power issues that will jump your ups and hit your connected equipment 
anyways.

Mike-