[conspire] Re PG&E causing downed trees (haha) and devices that deal with low-voltage [Re: A timely question.]

Tony Godshall tony at of.net
Mon Apr 23 14:35:24 PDT 2012

On Mon, Apr 23, 2012 at 1:34 PM, Rick Moen <rick at linuxmafia.com> wrote:
> Quoting Tony Godshall (tony at of.net):
>> Actually, its quite common on UPSs.  APC calls
>> this feature "AVR-boost" - a yellow light beeping
>> alerted one of our clients to this last week.
> I know it's common on UPSes, but I don't trust that very much.  As it
> happens, I have an as-yet-undeployed APC-model-something UPS in my
> garage waiting to serve my main machine and ancillary equipment.  When I
> get around to it, I'm going to check and see what they claim it will do
> -- but I have no intention of relying on that to protect my gear.
> APC is among the better manufacturers in that department -- much of the
> competition is unspeakable crap -- but the particulars of what they
> _actually_ do in real-world varying-voltage condition is too murky for
> my taste.  E.g., they 'boost' at a set low voltage by drawing on battery
> power and, what, inverting it?  But for how long, and then what happens
> after that if the low-voltage condition persists for a while?

I don't know how authoritative this is, but it sounds reasonably good to me:


> If I had my druthers, I'd prefer a unit that simply cuts all delivered
> power when the voltage is too low, and keeps it off until incoming power
> is back within spec for a while.

I'm sure that's doable- you could probably hack something
together with an arduino and a relay if that's what you really


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