In article <telecom24.275.11@telecom-digest.org>,
bonomi@host122.r-bonomi.com (Robert Bonomi) wrote:
> It should be obvious that any such device will need to be powered by
> some sort of UPS. Whereupon you may as well use a UPS. <grin>
I don't see why a simple power monitor/logger gadget can't be battery
powered, or more precisely, line powered with battery power to carry
it over the hopefully rare occasions when the line power fails,
preserving the already logged data and keeping its internal clock
running. We're talking about logging mostly short losses of voltage
in household electric service that's mostly on -- and battery backup
should keep a simple logger gadget running for days if not months.
In my household the built-in wall oven apparently has a built-in
battery; it's clock and other settings will still be valid after a 20
minute outage. Some electric clocks and most of the cordless and cell
phones will retain settings for a day or more; and of course all the
laptop computers for much longer. The thermostats for the HVAC ditto.
The microwave oven's clock display, however, is flashing "==12.00=="
over and over after even a sub-second glitch, as are many other
electric clocks. The coffee maker with a built-in auto-start feature
to make coffee just before 6:00 am each morning has lost all its
settings -- but comes back up with its heating element still on if it
was on when the power failed; lovely safety feature, that.
Most annoying is the expensive, highly touted Bose radio: it loses all
its settings -- time, station presets, etc -- on even the slightest
power glitch. (Lots of other things not to like about this overpriced
radio as well -- DON'T BUY BOSE is my recommendation.)
> Most modern "smart" UPS systems have a capability for signalling a
> host computer about the state of the incoming power, and the state of
> the UPS batteries. Allowing, among other things, 'controlled'
> shutdown of a UPS-protected device when the UPS batteries are about to
> expire.
Sounds like I'll have to look at this -- but I don't really want UPS,
especially for the household appliances, and would initially just
like to assemble some data on how badly PG&E is really doing.
[TELECOM Digest Editor's Note: Now wait a minute! I have a Bose radio
and that does not happen. The radio has a battery compartment which
keeps everything in place. The battery does _not_ continue to play
the radio, but when our power goes out here, I do not have to reset
the clock or the presets, etc. Do you have a battery in your Bose
radio? PAT]
AES (siegman@stanford.edu)