[TowerTalk] Whole House Surge Protectors

[Jim Lux]

At 07:34 AM 4/12/2007, R. Kevin Stover wrote:
>Jim McDonald wrote:
> > I have an APC Smart-UPS 700 that I bought from RefurbUPS.com.  I can't tell
> > in the information I have which type of UPS it is.  Does anyone know?
> > Thanks.
> >
> > Jim N7US
>
>
>It's a consumer grade switching UPS with a 500W capacity.
>
>It'll hold half load (250W) for about 14 minutes and full load for about
>4.5.
>
>It's designed for PC's and has either a serial or USB connection which
>will allow software running on the PC to catch a signal from the UPS to
>start a graceful shutdown of the PC when the UPS reaches a user defined
>level of discharge.
>
>It is a switching style of UPS and not a 100% inverting style.
>In my experience with them they are susceptible to RF and "dirty" line
>power. If the source varies in frequency or voltage by more than about 7
>- 10% the relay will constantly trip in and out.
>
>The 100% inverting style of UPS is what you want. They are more
>expensive and probably don't come in VA ratings of less than 1,000.


One needs to consider what problem you're trying to address..

Is it non-stop operation?  UPS is the answer
Is it line voltage regulation? voltage regulator or static inverter UPS...
(note that most equipment these days can tolerate pretty wide voltage 
fluctuations)

Is it RFI/transients?  Low Pass filters work great.. BIG inductor and 
some capacitors.. Sure, you'll get some voltage drop, but most 
equipment can tolerate 95V ..

Jim, W6RMK