On Wed, 21 Feb 2007 21:14:45 -0600, clifto wrote:

John E. wrote:
I'm looking for the most economical means to monitor mains voltage for spikes
and other such disturbances over an unattended period of time.

I'm not positive of this, but I believe some of the UPS systems that have
cabled monitoring, i.e. hook to your computer via serial port or USB,
will give a power line reading if queried. Don't ask me which ones. I
know my TrippLite 1000VA unit has a front-panel display and I *suspect*
it would tell the computer the line voltage if asked.

Now that you mention it, my PowerWare UPS does have this feature, and
a program can record line conditions based on a polling interval.
Probably nto the best solution however since I am sure short (single
cycle) faults will be lost in this setup.

Another alternative is eBay. I see products like the Amprobe monitors
(older, chart type) selling for about $100 or so. Hell, I'll sell mine
for that! bg