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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
A UPS only outputs power to the protected connections, the only person getting shocked would be the OP if he forgot to turn off the UPS before doing electrical work in the single room he was planning on giving backup power to.
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First of all, don't muck with your house wiring. It would be far better to reorganize your room around the UPS than to change the wiring inside your breaker box. It's unlikely that it would be legal and if there ever was an issue concerning fires or insurance, your ass would be in a sling.
As to batteries, I have an old surplus 700 watt APC UPS that I run 4 servers and a couple of switches on. The batteries were dead when I got it and I jury-rigged 2 garden tractor batteries in series to it. It works perfectly, but your mileage may vary. The UPS manufacturers generally *do not* want you to do this, so do it at your own risk.
"Eve of Destruction", it's not just for old hippies anymore...
Don't even think about doing this without talking to your city's electrical inspector. She will, of course, laugh you out of her office.
The UPS is an appliance, not a fixture. It has to be separable from the building wiring by a plug. It doesn't carry the appropriate ratings and classifications for being wired-in. Use the appropriate output cords and power strips.
That being said, you might want to do some research into generator transfer switches, and the idea that some of the house's loads would be on a separate panel that gets backup power.
"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?"
Considering that you're married, are you really sure that you want to embark on a project that has the potential to make you a permenant laughing stock at the beauty salon?
"Derp de derp."
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.
If you're trying to keep working during a blackout (as opposed to keeping your RAID consistent), look into these: a Kohler Generator. Sure, you still need a small UPS for your server/desktop, but it only has to last ~45 seconds until the generator kicks in. Have an electrician (or authorized Kohler rep) install it. I wish I had one sometimes.
YMMV
If you really want to isolate the system look into installing a photovalitile roof system. Not only can you keep your whole house up and running during power outages, you can reduce your monthly power bill. ;) And those system, while still a challange to get OKed by the building inspector, can get federal and state funding, tax incentives, and even cash from your power company.
See http://www.dsireusa.org/ for more info on your local photo volatile power system incentives
-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
Besides the electrical code violations, you'll loose flexibility in what you can power in the room. Laser printers and other very high current appliances (maybe microwaves?) will not be good for your UPS. I've seen laser printers cause UPS's reset themselves. It's not fun having workstations loose power every time someone tries to print. =)
For whatever reason, over the last 10 years, I have seen more power failures being caused by a UPS then being handled properly by one.
The idea seems to be good and usefull, but so far reality tells me that those devices do not have the kind of reliability that is needed.
One of my customers has their entire computer room wired up to a HUGE UPS, and has a few smaller ones in place for very important servers. The big UPS is supposed to keep them running for as long as power lasts, the small ones are to allow those servers to properly shutdown when power runs out on the main UPS.
In the last month, they had 2 major failures of the main UPS, resulting in a substantial amount of downtime. They cannot remember the last failure of mains power (I do, and it is a few years ago now)
My own company used to have a very nice IBM AS/400 with UPS (one made specifically for this machine), which failed during the one power failure we have had in the last couple of years here, not to mention it deciding to just switch off a few times over the years.
Another one of my customers runs a bunch of servers with redundant power supplies where each power supply has its own UPS. That setup sees to work a lot better already.
To me the story seems pretty simple:
I know a guy who gets old UPS' from the junkyard and then hooks them up to regular car batteries. They work great and last for a lot longer than the batteries that come with them. Not sure what you would need to do to scale that up to your application, but you should be able to save a ton of cash.
there are 2 kinds of people. those who divide people into 2 kinds, and those who don't.
...for a couple of reasons. Firstly, you don't want to run the entire room off of the UPS; just your critical computer equipment. My UPS runs my workstation, the router, one display monitor, and typically a linux file/web/services server. It also runs my desk lamp. The UPS I use in particular is nice (and I believe mine is related to yours, in brand) because it has this warning alarm when it's power becomes the primary source of energy. The reason for this is that my particular outlet (I live in an apartment with three other people) is wired to a pair of lightswitches on anterior corners of my desk. We've also noticed that when you turn something on in one part of the apartment, the power will occasionally spike, and without the UPS, reset someone's workstation. But I digress, don't plug the whole room into your UPS. Just what you need on to perform an adequate shutdown of your equipment, in the event of a power failure. Secondly, if you put the UPS on the source side of your breaker, and your house gets struck by lightning, your UPS is going to BLOW UP. And I don't want to be anywhere near it if and when that happens. Circuit breakers are there for a reason. Sure, they aren't the end of the line in protection, you need a surge protector, too. Now, my UPS does have a surge protector in it, but still, I'm sure you see my point by now.
Informatus Technologicus
> Is the UPS that I have sufficient to run a whole small office?
Yes.
I, too, had a surplus UPS about the size of yours. When I
was in my apartment, it sat in the same room as my computers.
The UPS was loud, ugly and produced lots of heat. (Much like
a girl I used to date... but that's an another story for
another day.) It protected my computer equipment but not my
TiVo or home stereo equipment because they were in another
room. So, I had to have a seperate UPS for them.
When I bought a house, I didn't want UPSes spread all over
the place nor did I want the heat or sound inside the house.
So, I put the UPS in the garage and then wired UPS outlets
where I needed them. I have a quad-outlet in the office for all
our computer equipment. I have a quad-outlet in the living room
for the TiVo, stereo and TV. My cordless phone and answering
machine also plug into a UPS outlet.
For nearly five years, this setup has worked great. Every
two or three years, I have to replace the two batteries ($90).
Other than that, it has been great.
Plus, I have disaster-recovery outlets spread throughout
my house. When last year's hurricanes knocked out power to
my house, I was able to plug the UPS into our small generator.
I didn't run the computers or television (but did keep the
TiVo online so I wouldn't miss my shows) but I was able to
keep some lights on without having extension cords pulled all
over the house.
> I want to find the breaker for the room, and after the
> breaker, run the power through the UPS and back out
If I were you, I'd run a new circuit. You never really
know what outlets and appliances are where. When I moved
in, the toaster's outlet in the kitchen was on the same
circuit as the outlet on the front porch where I plugged
in my hedge clippers.
I'm sure there is more on your office circuit than
you know about. It is best to start clean. Plus, electrical
work is really easy if you have attic or basement access.
Matt
I've been saying this for years. Unfortunately my only multiple-power supply box (second-hand, cheap) has a single inlet plug, so it would take some work to run each power supply from its own UPS.
In the telecomm infrastructure, everything runs from a DC battery bank, which is maintained by rectifiers. (Or you could say it runs from rectifiers, backed up by batteries. Semantics.) All the equipment has 2 power supplies, and is always fed from two separate DC inputs, known as A and B. In very small (remote equipment hut) installations, sometimes A and B are both fed from the same battery bank, but in most buildings, there are two strings of batteries. You could concievably blow a main fuse on one side, and the whole office would run from the other. (Everything's fused high enough that it can draw all its power from one side or the other, but in normal use, they split the load evenly.)
The DC infrastructure makes telco central offices ideally suited to solar-electric installations, since the inverter is a large part of the cost of a residential photovoltaic installation. (I don't know why we don't see this more often.)
Back to servers. I've got very little experience with redundant power supplies in the PC world. Is the APM/ACPI driver aware that one power supply has failed? Suppose you had one power supply plugged into the "house power" feed, and the other into a small "personal" UPS. Could software notice the failure and begin an orderly shutdown, or would the small UPS have to tell the server, via USB or RS232, about the fact that it's now running on battery?
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.
It's almost certain that the wall sockets in the room are daisy chained with sockets in other rooms and all off of the same breaker. Same deal with the overhead lights. This makes your plan somewhat physically impractical.
If you are going to use this unit (the UPS), get the proper replacement battery or batteries. Do not even think of using automobile batteries or anything like that anywhere indoors. Do not think of using those types of batteries outdoors with a long cord running indoors to the UPS.
Get a licensed electrician to install a separate 30 amp circuit from your breaker panel to a single outlet in the room you have set aside as an office and plug the UPS into that outlet. Make sure that the UPS is working properly before going to the expense of installing the outlet.
Use the UPS to power your computer equipment (and perhaps a low wattage lamp), excepting of course any laser printers or the like.
As long as you're going to be talking to a real electrician you might inquire about the feasibility of setting up a generator and the necessary equipment to switch between it and the power company's wires. Unless you get a *very* large generator you'll need to have things set up so that the generator feeds selected circuits in the house (lights, refrigerator, wall outlets, but not the stove, the washer, the dryer, the water heater, the heat pump, etc.) while disconnecting the power company so that there's absolutely no way for the generator to feed power back into the power company's lines or for the power company to feed into the generator's output. Whether you get a generator that starts automatically and automatically disconnects the power company and connects itself, or one that has to be started and switched manually depends on how much money you can afford to throw at it.
You may want to look into swapping this unit (the UPS) for 2 or 3 lesser ones that can be plugged into your existing 15 amp outlets if you can find someone in the reverse of your situation. That way you won't need any special wiring (unless you go with the generator idea).
I see even classic Slashdot is now pretty much unusable on dial up anymore.