[asterisk-biz] backup power requirements for emergency calling

[alex at pilosoft.com]

On Fri, 14 Apr 2006, Andrew Kohlsmith wrote:

> On Friday 14 April 2006 17:54, alex at pilosoft.com wrote:
> > This is why asterisk guys should stick to doing asterisk, and leave
> > facility management to people who know that.
> 
> Seeing as I am a field applications engineer for an industrial power
> electronics company with over ten years' of experience in this field, I
> find your comment not only amusing, but also downright incorrect.
In words of Randy Bush, I encourage my competitors to use you for the 
electrical engineering. *plonk*

> Asterisk is my hobby, but one I am very good at. 20 minutes may have
> been a bit of a stretch, but I typically see 50% usage on the UPS before
> the genset is started.  You do *not* want your 600kW genset cycling for
> 2-3 minutes whenever a squirrel or raccoon falls across the lines or
> tries to nest in the transformer and trips the breaker, especially since
> the breakers will automatically try to clear the fault 3 or so times
> before staying tripped off and notifying a human.
I don't know about squirrels in your neck of woods, but over here in New
York, I've had my genset start exactly once in 5 years that wasn't a
"major power outage". (Major power outage = 9/11 and 2003 blackout).

Starting genset is a minor price to pay for assurance that your stuff is
operating properly *at the moment of the outage* and UPS batteries won't
be unnecessarily drained.

Besides, no ATS will run genset for 2-3 minutes, they all have "30 minute
minimum" and then "spindown" time.