Typically telco setups have about 30min-1hr of AC UPS capacity and
4-6 hrs of 48V battery capacity. Last time i was at MAE-East it
didn't have any backup AC power and a nice DC setup.
BTW, the cheap solution for DC hookup would be using a power inverter.
This issue of AC v DC and reliabilty of facilities is interetsting. We
co-locate equipment at several telcos, and they co-locate equipment
with us out west. We prefer DC wherever possible. This is because the Telcos
don't depend upon anyone but themselves to provide reliable and clean power.
Another way of looking at it is that if the telco goes down, then the
application layers above are useless.We just received the first of several
7507s to that end....all DC.
Our real problem is getting them to fit properly in 23" racks