Long-term (hours+) solution for power outage: PBX, lights, and computers

[Dave Johnson]

Ted Roche writes:
> A client suffered a five-hour downtime recently, and has been looking  
> for a reasonably priced solution. He's working out of leased office  
> space, and a generator or major structural changes are unreasonable.  
> He happened upon:
> 
> http://www.sentrypowertechnology.com/
> 
> And they offer 6 KW and 12 KW units.
> 
> The client would like to keep a half-dozen computers, LCD screens and  
> a laser printer or two running for a 4- to 6-hour period. Anyone have  
> experience with a solution that would work? Things to look out for?  
> For example, each computer has its own small APC UPS, so there would  
> be two sources of battery power in series. It's possible the  
> generated AC would not be stable enough in voltage or frequency to  
> keep the UPSes from tripping on and off. I know this is a problem  
> with the smaller, less-regulated generator units.
> 
> Is there a good solution for a small office? Of should he be looking  
> for a 10K VA UPS?

Most UPS manufacturers have extended-run models that you can attach
multiple external battery packs for hours and hours of runtime.

Are we talking about equipment that is distributed throughout the
office or a bunch of network equipment and servers?  If they are
centralized then one big extended run UPS is in order.

It's generally not a good idea to chain UPSs.

For really long run (4+ hours) a generator to power the UPS is usually
a better solution.  3KVA-6KVA generators aren't that big, but you do
need to wheel them outside before turning them on.


--
Dave