[mythtv-users] OT: apc backup

[Stephen P Villano]

On 3/22/2016 6:47 PM, Simon Hobson wrote:
> Mike Thomas <mt3 at pfw.demon.co.uk> wrote:
>
>> Mr. Hobson's experiences lead me to wonder whether these APC UPSes can
>> be installed safely at all. Requiring a 125A circuit for a 3kVA unit
>> completely eliminates the chance of fault discrimination.
> It was (IIRC) 125A circuit for a 16kVA unit, and 32A for a 3kVA unit. Basically they expect a power supply rated for twice the rated load current which is pretty crap really given the real world constraints many people have to work with.
>
>> Honestly I would have thought better of Schneider.
> Well a lot of my experience is prior to APC becoming part of Schneider.
>
> One fun thing is if you are bigger than "just a few servers" but smaller than "datacentre". At my last job I went through a process of thinking about what was important and what wasn't. Some servers were basically not needed if the lights were out, others were used by remote sites even if we couldn't work. So it makes sense to shut some servers down fairly quickly and conserve power for the others - which allowed us to get from less than an hours runtime to keeping important stuff running for 4 hours (the longest power cut we had with that UPS in place). APCs answer to starting stuff up again ? Shut everything down and start up again - yeah right, the lights have just come back on so the key systems and phones go off for 10 minutes !
>
>
We had the converse, where uptime was mandatory in a DoD environment.
The problem was, the building UPS worked great, but the racks of
batteries were defunct. It took an outage that dropped the entire
building and hence, all war communications going down for 12 hours to
make replacing the defective batteries a priority.
Having no telephones for 8 hours as the SL100 booted up really spurred
replacing those batteries, plus the four star general raising merry hell.
Then, the generator failed, as a water leak displaced the diesel in the
underground tank...