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Jerry Peters Jerry Peters is offline
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Default Hacking APC UPS's "Master/Controlled" Feature?

"(PeteCresswell)" wrote:

I want the "controlled" outlets to be controlled by the "master"
outlet - at all times, as I think most people would impute from
what it says on the box the power supply comes in - not just when
there is external power.

The reason: if the power goes out, I still want connectivity
across the LAN, but I don't want the UPS' battery tb drained
(which shortens it's life).

Sequence Of Events:
- Power fails

- UPS keeps supplying power to PC connected to "Master" and to
devices connected to "Controlled"

- UPS sends message to PC telling it that we're on battery backup

- PC keeps on truckin'.... with LAN connectivity still intact

- PC's Power Management utility kicks in and, after a preset time
or a preset remaining battery life, commences a graceful
shutdown of the PC

- PC shuts down.

- UPS then shuts down the router, switches, and whatever else is
plugged into "Controlled" outlets.

- The UPS battery does not get totally drained.

Maybe I'm the only one.... But this seems so obvious that I just
can't imagine any other implementation in the context of an
Uninterruptible Power Supply.

The power-saving thing sounds nice, but I go back to the fact
that this is an Uninterruptible Power Supply, and not just a
power strip.

This may sound like nit picking.... but it's not quite true that
they are only supplied with power when the computer is up. What's
true is that they are only supplied with power when the computer
is up *and* there is external power.

Where are they getting power, if not from the UPS?

And would you want your laser printer to keep running from the
battery? The design seem sensible to me.