Back-UPS garbage? (was: Quick survey -- UPSs on slave nodes?)

Robert G. Brown rgb at
Tue Feb 11 08:58:05 PST 2003

On Tue, 11 Feb 2003, Drew Raines wrote:

> I work in a university research building where you'd expect the
> power to be consistent, especially since the whole medical center
> is battery-backup'ed (critical hospital systems being the primary
> reason).
> Oddly enough, we see those spikes or flickers all the time, so I
> got a Back-UPS 350 with the hopes of doing exactly what you said,
> surviving the frequent, short, outage.  No go.
> After trying two machines and a monitor on the battery-backed
> plugs, just the two machines, and finally just one machine, I got
> the stupid thing to provide a couple seconds of life.  But that was
> it.  The box said 17 minutes under average load.  I'd think one
> 200-watt power supply would be average enough.
> That was my Dell Precision 530 PC, sans monitor.  When I tried only
> my Sun Ultra 30 (again, no monitor), *beep*, reboot.  

That's very odd.  I got (I'm pretty sure -- I'm writing this at Duke but
the units are at home:-)

UPS-330   Smartlink 330VA UPS   Active   37.99 

(the latter being the price, from my local vendor).  Capacity
for really just a single system, or maybe a system plus monitor, for a
few minutes at most.

I plugged in a pretty much standard OTS desktop computer (800 MHz
Athlon, 17" monitor) and it runs fine.  I yanked the plug out of the
wall to test it, and it ran fine, no crash.  I didn't run it down to the
point of a crash, but it kept the system operating for perhaps a minute
before I plugged it back in, no worries.  And as I said, we've had a
couple of those "one beep faults" (where all the five or so UPS in my
house have time to beep once before it comes back on) that they've
bridged transparently, where the one remaining unprotected box crashed.

Maybe you have defective ones?  Have you tried returning them for
replacements?  Are you sure the internal batteries are actually
connected -- some units are shipped with the batteries not plugged in.
It seems really strange that it can't even support a single PC, sans
monitor, for a whole minute.

> Long story short, I replaced it with a Smart-UPS 650 which seems to
> support both systems through mild outages.  For $275, though, I
> wanted it to log in, check my e-mail, and respond appropriately to
> outstanding messages before it signaled a machine to halt.  Oh
> well.

Yeah, I was hoping to avoid more of the $200+ UPS in my house,
especially because I'm protecting systems all over the place and can't
run two on a single device.  So far the 330VA cheapie seems adequate for
a single desktop computer for at least a minute or so of outage...


Robert G. Brown	             
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at

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