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Running a Home-Office Through a UPS
mwagner_00 asks: "After spending lots of money and time, I now have an office in my home. My wife and I both have computers (mine is a high powered gaming rig), and I also have a workbench where I work on other people's PCs. I have a web/email server as well. I would like to protect the investment by running the room's power through a UPS. I have a APC 3000NET that my workplace was going to throw out. The only thing it needs is a good set of batteries. Has anyone tried something like this before? Basically I want to find the breaker for the room, and after the breaker, run the power through the UPS and back out to the room. Is the UPS that I have sufficient to run a whole small office?"
A surge strip and extention cord for the work bench. If you are going to try to patch into the house wiring you're going to want a certified electritian, and depending on housing codes in your area, you may need a certificate from the building inspector.
Much easier to mount the UPS under the work bench and to run an extention cord/surge strip to the other PCs. You don't want to have anything running off the protector you don't need. Things like speakers, printers, PDA chargers, etc.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
The specs say 2250 watts. 2250 watts divided by 120 volts = 18.75 amps. So, in theory, you could hook this to a circuit with an 18 amp fuse or breaker.
Of course, doing this is surely a crazy violation of electrical codes. Would it be that hard just to plug the computers into the UPS? It has plenty of outlets, it really looks like that is how it was intended. Wiring it right to the electrical box might get you some geek points, but you might also become a Darwin awards nominee.
I doubt it is worth it.
First off, you do not want to put the UPS in like that for the whole room. I'd say if you really want to put it in in this fashion, make dedicated circuits (like in some datacenters) beside the regular circuits that are UPS'd. That way you have a choice of outlets... Anyways...
You kind of need to specify the kind of loads you'd like to put on the UPS. What you'd need to do is look at how many machines, how many monitors, etc.
For instance, you do NOT want to put lighting (flourescent or otherwise) on a UPS.
I have an older APC 900 that has external modules that I can add battery packs to, if I want a long runtime.
I'm rambling, but a 3000 will power a lot of equipment, for a short amount of time. The batteries for the "higher numbered" UPS's seem to be pretty small, so you don't get much runtime out of them. For a quick-and-dirty of how long, get an estimated wattage you're going to draw from the UPS. Then, take battery voltage, multiply by number of batteries in the UPS, then multiply by the AH of ONE battery. That gives you the watt-hours of your UPS.
If you're going to draw 450 watts from a UPS and the batteries add up to 450 or so, then you'll get about 1 hour - 20%.... Efficiency losses run about 20% (I'm guessing here)...
Anywho. My 900 runs a file server, switch, cable modem, sipura phone box, and the gateway for about 2 hours. It only has one battery pack, but my battery packs are 4x(12v*18AH), which is around 864Watt Hours. So I'm probably drawing 400 watts continuously through the UPS....
Karnal
Line-interactive UPS units like the 3000NET DO NOT filter power. They have AVR, which only filters huge changes in voltage. It will not kick in for even extremely dirty power. It is simply meant to boost up the voltage if your power drops down to, say, 90 volts, or goes up to 150 volts.
So keep in mind that really all the UPS is going to give you that a good power supply can't is battery backup and surge protection.
1) Many houses and apartments are not wired the way
you think; all the outlets in one room may not be
on the same breaker. Other rooms may have outlets
on that breaker. Lights may or may not be on the
outlet with that breaker. IOW, you would need to
test thoroughly, and probably do some rewiring.
And you still might miss something.
2) If you miswire anything and the house burns down,
your insurance may not cover you. You'll need to
check what the code is where you live and look into
inspections. Getting a licensed electrician involved
is a good idea.
3) You don't want to plug your vacuum cleaner into the
output side of your UPS; not great for either one
of them. Sooner or later, something like that will
happen.
4) If you have a laser printer, startup surges can be
huge; not a good idea to be on the UPS.
There are others, but this should be enough. I have
to go along with the people who receommended running
one (or however many) separate outlets for the UPS.
These can be current or new outlets wired to the UPS
and *clearly labeled*. Maybe use red covers or something,
with a label "Computer equipment only" or "Ask Fred
before plugging anything in here". Of course, you'd
have to change your name to Fred.... Depending on who
could possibly be plugging things in, you could even
consider switching to no normal outlets; hardwire some
power strips into a junction box, and bolt them underneath
the desks the equipment sits on. The biggest problem with
that is moving the desks.
And finally, what happens when you move? You need to make
sure this isn't too hard to reverse, or consider what
happens if you leave it. You don't want someone coming
after you with an axe or lawyer later.