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(PeteCresswell) (PeteCresswell) is offline
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Default Hacking APC UPS's "Master/Controlled" Feature?

Per Nelson:

I don't understand what you want. Do you want the "controlled" outlets
to continue to have power after the computer shuts down? There are
other outlets that operate independent of the "master" which do that.
As I understand it the idea behind the "controlled" outlets is that a
peripheral which is only used by the computer, eg a printer, doesn't
need power if the computer is down, so to conserve the remaining
battery power for the useful items, these are shut down in synchrony
with the computer.

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.

I have one of these and it works just fine. There are "uncontrolled"
outlets which are supplied with power whether the computer is up or
down, "controlled" outlets which are only supplied with power when the
computer is up,

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.

and surge protected only outlets which are not supplied
with backup power. I would have chosen the mix between these
differently, but that is easy enough to get around by plugging power
strips into one or the other types of outlets.

In my set up, I have the external hard drives and printer connected to
the "slave" outlets and the cable modem and VOIP modem connected to the
"always up" outlets.

When the battery is down to 25%, the computer
shuts itself down along with the peripherals and the modem and router
continue to provide telephone service. Isn't that the same thing you

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