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Need... More... Power...
MikeDawg writes "After dealing with the headache of never having enough electrical outlets, not having a cable TV coaxial, not having a telephone hookup in the right places of my apartment, I found this article at CNN. It is nice to see that college dorm rooms are getting filled with outlets to provide students with enough hook-ups with for all their electronics. My question to you (renters/dorm-room dwellers) is does your dorm room or apartment have enough outlets, whether it be electrical, cable, telephone, or anything else you may need? What do you do in a situation like this? Do you load up each socket with a 10+ port power strip (or battery backup as it may be) and pray that you don't knock-out the circuit everytime you start burning a CD?"
Remember that Slashdot story a while back, about the guy who made a fusion generator in his dorm room?
:)
He made it for fun: I NEED it
I'm amazing. You aren't. SUCK IT
have you considered using a bicycle generator? i.e where you have to pedal for 5 hours a week to charge up a battery which can supply enough power for a TV for an hour or so?
When anger rises, think of the consequences.
Confucius (551 BC - 479 BC)
One of the reasons they're doing this is that students often tend to use multiple extensions on a single outlet, which is the second leading cause of fire deaths, according to this.
In fact, the recent Moscow dorm fire that killed dozens and injured hundreds more was caused by such a fire, by a computer science student with dozens of electrical devices in his dorm. I suppose universities don't want such a thing to happen here.
http://seattletimes.nwsource.com/html/nationworld/ 2001802164_dormfire27.html
You'll need a few basic tools.
Saw-zaw
Screwdriver
Wire Cutters
Electrical Tape
Cinnamon Rolls
Gloves
Using the sawzaw, carefull make an incision in a wall adjacent to the next dorm room. Put on the gloves and extremly carefully use the wire cutters, electrical tape, and cinnamon buns to wire in this "new found" power source.
You may want to use some "mud" and sheetrock to restore the wall surface to its original state.
Enjoy!
clifgriffin > blog
...but hopefully the colleges are putting a little thought into their designs for the dorms. While it's true that outlets are usually in short supply, you can still be up an electrical creek without a paddle if all the outlets are on the same (underpowered) circuit.
A lot of apartments suffer from this problem as well no matter what their age... I have lived in an apartment that was over 20 years old, and it had a total of three ten-amp circuits for the entire place (not counting the circuits for the appliances which are pretty much dedicated). This was not exactly optimal for supporting five PCs and their peripherals along with a SUN Ultra 450. I've lived in newer (5 years old or so) apartments that had the exact same problem.
It's my opinion that the best thing you can do is go to Radio Shack and invest in one of those Circuit Detectives. Use that to determine what outlets correspond to which breaker, and how much power you have through that breaker (the ratings are printed on their for your sanity). Once you have that figured out you can begin learning the fine art of load-balancing on your outlets. "Let's see, I have 2 amps for my PS2 here on circuit A, and 3 amps for my TV on circuit B, and 2 amps for my PC on circuit A...."
If I had to build a house now, I would definitely recommend going overboard with the electricity, gas, aerial and cat 6 cabling.
:(
It's good advice. I regret not doing extra drops (cat 5e at the time) when remodeling. I have a minimum of 3 ports per room, and I find that I'm always running short. Coax for the television is even worse - the electrician who did that drop only did one drop per room. This is very inconvenient if you want to put the tv on the side of the room opposite the coax outlet.
The most important thing if you're doing new construction is when doing the blueprints, design the house so that all of your water, cable, and electricity runs are accessible, and centralized. Residential contractors build so that you won't want to do maintainance - they staple wires in place, embed pipes in concrete, and do other things to discourage you from "upgrading" your house. Don't forget to put electrical, networking, and cable in cabinets (you'd be surprised how handy that can be - I wish I had done it), and give your garage/attic/basement a double-helping of everything, plus a main feeder big enough to supply another sub-panel/subnet worth of power/bandwidth. In this case, I told the idiot architect to give me a 80amp run to the attic (don't ask me why, just run it), but he ended up omitting it and not telling me.
By coordinating all of your runs via a central location, and making sure that you can access it, you can leave room for future expansion. Better yet, locate all your networking equipment there also, and soundproof the sucker. I sort of have this arrangement now (centralized location), but all the runs are embedded in drywall
Remember, if you hire a contractor, YOU MUST CHECK THE WORK. If you hire an architect/general contractor to implement things, YOU MUST CHECK THE WORK. This is year 3 of living in this house, and I'm still fixing electrical problems, correcting defects in cabinetry, patching walls and stucco, and replacing worn out plumbing. No, I didn't hire these guys, if I had, I would have kept a closer eye on em.
let's make some REAL calculations....
Computer - From 350 to 550 watts. monitor? flat panel LCD - 20 watts. a 17 -19 inch regualr monitor? 170-200 watts. Speakers? from 30 watts to 200 watts or more.. PDA 20 watts charging.. usb hub 15 watts, small 100 base switch and/or your smc firewall to hide and protect 60 watts.
now that is just a base computer. no printer (80 watts for a cheap inkjet 300 watts for a small laser printer)
Let's add a cheap fridge.. a $59.00 cube fridge= 500 watts. almost every dorm room has one. as the crap 6 can fridge from think-geek is worthless for a dorm.
my 9 inch TV here uses 160 watts on it's own.. and then you mention a stereo... maybe a cheapie boom-box will use 300 watts, a regular stereo uses from 500 watts to 3,000 watts depending on equipment, amp power, speaker load, etc....
and your 300 watt misc load... is a bit low...
anyways.. being conservative on the above figures.. I get 2070 watts drawn.. at 120 volts (average US voltage in the wall socket.)
I get 17.25 amps... enough to completely hose and set fire to a cheapie power strip. (if you did not pay $50.00 to $100.00 for your power strip... it's a cheapie.)
that will strain a 20 amp breaker (inrush current will be much greater than 20 amps.. more like 35 amps if you were to turn everything on at once.)
and it is rare that contractors wired the place correctly with 12 gague copper and 20 amp breakers. most contractors cheap out and run 14 gague and use 15 amp breakers... betting that your dorm room is on one breaker for it's outlets and one for lighting, ahared with others..
and from what I have found myself in the 80's in college, and my nephews now in college... this is true. each room is given 15 amps typically for 2 people to share. the above list is not a workable load and therefore usually the stereo get's chucked and they use the computer as a stereo.
god help the students if they are geeks and have 2 computers.
Do not look at laser with remaining good eye.
holy crap you are giving him bad advice.
Sure you can get the type that goes in the breaker box (a good idea in fact), but that doesn't stop the same level of surgers as the power strip will.
so your lack of knowledge is dooming this guy to have sub-standard wiring. Very Nice of you.
most quality whole house surge supressors are at least 20 times more effective than the crap you can buy even for $100.00 as a plug in strip.
My IsoBar whole house supressor with replaceable surge and filter modues was not the top of the line for whole house and still had ratings that were far higher than even the "audiophile" quality power strips.
plus it's reaction time is at least 300% better so the power spikes dont get past it... unlike all power strips as they lack a solid ground to drop the surge to... they can be fast but they dont have a ground that is effective for dropping a 4000 volt spike.
I really feel for people buiulding a house and taking advice from amateurs that really dont know what they are talking about.
USE WHOLE HOUSE supression, period. if you have a home theatre, add a second whole house supressor and noise filter if you really think you need it.
A properly designed electrical system in the home with the correct surge equipment at the front end (the electrical box) solves all these problems. from surges in the house from flipping on grandma's 40 year old stand mixer to nasty surges from the factory down the street.
Do not look at laser with remaining good eye.
OK as somebody that can spec eletrical this is plain BS. Those cheap surge strips are not capable of dealing with large spikes due to poor grouding. Whole house units dont protect you from that 2000 watt hair drier (BTW you can not get 2000 watts out of a 15 amp plug per UL you should only draw 80% and thats 12 amps for 1320 watts max same for those vacume cleaners)
Anyway enough ranting for a good home entertainment setup you would want at least one dedicated circut perferably 20 or 30 amps if you can use the 30 amp back 20 amp front recepticals in your building code . A single line surge or UPS unit might also be a good idea (something in the nice back APC RM line but thats over a grand in UPS) especialy for the Tivo and Replay users but also for the big screen TV guys. I say UPS simple because loosing power is hell on any device while it's working and the brownouts are also hell when you remember that modern eletronics are never realy off unless unpluged remotes and all that.
No sir I dont like it.
In practice you'd like a power bus fed by some big central PS that doesn't depend on the computer. This PS would provide for standby power to peripherals, like the ATX standard. Compliant peripherals would take a trickle of power from the bus during "sleep", and wake up (turn on their main power supply, reset and boot) on some electrical command. Some other command, or a sustained period of inactivity, would set them back to the sleep state.
This is pretty much what many cars have today, using the Controller Area Network (CAN) bus. CAN modules "sleep", some with their RAM powered on and all with their comm chips running, on less than a milliamp. The speed is not up to computer specs (0.5 mbit/sec or so), but the techniques could easily be adapted to something like FireWire if the will existed or one manufacturer had the pull to create a de-facto standard. With something like this you could have a "power strip" like a laptop brick, putting out 12-14 VDC for a host of peripherals and maybe the computer as well. You might not get rid of all the wires (though a combined power/data bus could do that too), but you'd certainly get rid of all the wall-warts. It would make backup pretty trivial, too (just hook in a deep-cycle battery). Who wouldn't want that?
Time is Nature's way of keeping everything from happening at once... the bitch.
anyways.. being conservative on the above figures.. I get 2070 watts drawn.. at 120 volts (average US voltage in the wall socket.)
My quarterly electricity bill is approximately 45 all year round. The power costs about 5.6p/kWh, so anybody with a calculator can determine that the power draw of this house averages about 400W.
Peak power usage for the house (excluding hardwired appliances, i.e. cooker, shower and washing machine) is less than 1kW. Perversely, I can draw 3kW from a single outlet (13A at 220v) - and there's four per room.
However, what I really want to know is how a student in a dorm room requires two to four times the power of a house with two geeks, a half dozen computers, plus our other toys.
Just daisy chain like fifteen surge strips together. You end up with tons of usable outlets. Use extension cords + more power strips to get juice to other parts of the room.
Hint: Hide all of this under a pile of clothes or under your bed so the fire inspector doesn't see it.
I'd rather be a conservative nutjob than a liberal with no nuts and no job.
When I was living in a dorm, the substandard wiring had a hidden benefit. Every room and half shared a circuit- I was in a "half" room- one wall shared the circuit with the entire room next door, and the other wall shared with the room on that side. This gave me final veto authority over either of my neighbors' (usually poor) choice of music. I had a cut of lamp cord with the wires twisted together inside a big ball of electrical tape. Plug it in, it shuts off your neighbor's stereo (and everything else!). One semester I had a neighbor who liked to blast "Freebird" every afternoon. After the sixth or seventh time I used my "remote", he was out in the hallway swearing about the lousy dorms. A girl walking by innocently suggested that maybe his stereo was blowing the fuse. She didn't know how right she was!
Just do some simple math and you can avoid overloading a circuit.
1) Determine the rating of the circuit -- I imagine each dorm room will have one circuit. (Maybe two)
2) Determine which outlets go to which circuits. If outlets are close together, then they are probably on the same circuit.
3) Calculate the amps of everything you are plugging into the circuit.
4) Add them all up.
5) If they are close to or over the amp rating for the circuit, then you have a problem, and you will have to unplug stuff.
Important points to remember:
* Don't forget to check the rating on any power strips that you use! Most are rated at 15 amps, which is probably the same as the circuit you are plugging into.
* Circuit breakers can momentarily handle more than their rated amps. ie: it might be able to handle 17 amps for, say, 30 seconds before tripping. The higher the amps, the faster the trip. A direct short will (er, should) instantly trip the breaker.
* Not everything has the amps listed -- some devices only list the watts. You can calculate the amps by dividing the watts by the voltage. ie: your 400 watt computer running on 120 volts will have a max amps of 3.33.
* If you are in a situation where you have two circuits near your computer, and you overload one, keep this in mind: It is generally a Bad Idea to plug some peripherals into one outlet and others into another. Subtle differences in voltage and phase can lead to a net difference in voltage between your equipment and lead to permanent damage.
* This may be unfounded (someone correct me if I am wrong), but I always think that it is more dangerous to overload a power-strip than an outlet--meaning that I trust the circuit breaker in the closet more so than I trust the power strip.
I hope this helps. If you read this and go kill yourself, it's your own damn fault. Use at your own risk. Use common sense, and remember that this IS slashdot.
— darco
have you considered using a bicycle generator? i.e where you have to pedal for 5 hours a week to charge up a battery which can supply enough power for a TV for an hour or so?
I've thought of that before. You know, it's a great idea for a few reasons:
I do have to wonder about how bad this dorm room power crisis really is. Let's consider appliances with realistic maximum power consumptions:
Note that many of these loads are intermittent or mutually exclusive. Most laser printers only pull any amount of power when the printer is actually fusing a page. The boom box probably won't be playing loudly at the same time as the computer speakers. And, unless you like to leave the door open, the beer fridge's compressor should be off most of the time.
And some of these appliances will become duplicates in a shared dorm room, so the realistic likelihood of them being on at once is small.
1830 watts is the total power consumption for the list of appliances above. In my jurisdiction, commercial buildings (including University residences) have one outlet per 1500W circuit. Most circuit breakers are thermal (takes time to heat up a bimetallic strip in the breaker) and therefore act like slow-blow fuses. And unless you're printing a massive pile of course notes while playing the boom box and computer speakers loudly and doing it with the beer fridge door jammed open, the loads are probably going to be too transient to trip the breaker. So you may have a whole load of power bars plugged into that one outlet, but in reality, it's likely to be perfectly fine.
On the other hand, dorm rooms are small. It's in the students' best interests - forget power consumption - to slim things down:
Noting that this scheme is merely a common-sense approach to giving you more space in your dorm room (and making moving at the end of the year that much less painful), your maximum consumption will only be about 1260 watts. Which means that if you've got a circuit, you're fine.
I'd suggest to universities that they point out in their residence brochures something along the lines of "Moving into and out of residence can be unpleasant. For that reason, we suggest that students attempt to travel as lightly as possible. LCD monitors and video cards with TV inputs will save you space by avoiding having to carry around bulky CRT displays." Maybe offer a small rebate to students who use an LCD monitor and TV-in video card to replace a CRT-based monitor and TV set.
Fire and Meat. Yummy.
c) run my computer and cook
You have an AMD, right?
thats why you buy a router, use the MAC address on it from your computer, and plug in as many damned machines as you wish.
Yeah, I hate my schools network policy too.
In my first dorm there were 5 outlets, 1 of which was ungrounded (above a mirror). We were allowed hair dryers,
Heh... Note that those ungrounded outlets built into bathroom light fixtures are normally for electric razors only.
What's different about them?
When they say "RAZOR ONLY" beside the outlet, the outlet is usually on a small 1:1 power transformer. It's called an isolation transformer, and in those applications, they're usually only built to handle something under about 50W. Don't plug a hair dryer into it!
What does it do?
Ordinary outlets have a "hot" side and a neutral side. The neutral side is tied directly to ground at the distribution transformer and usually (depends on local electrical codes) at the fuse box. The hot side is connected to a winding on the distribution transformer which is putting out 120V with respect to ground. The power is then referenced to ground - usually to a cold water pipe which comes directly into the building through the earth.
Outlets also have a wide blade and a narrow blade. The wide blade is supposed to be connected to neutral, the narrow blade is supposed to be connected to hot.
Theoretically, you should be able to touch the wide prong and the ground (round prong) at the same time without getting a shock. The whole point of this is to allow you to accidentally touch the large part of a light socket base without getting a shock. Back in the day, lots of radios and TV sets used a "hot chassis" which was tied directly to one side of the power line - this should have been the neutral. (Most of them also predate polarized power cords, so depending on which way you had it plugged in, you had a 50% chance of the chassis being at 120V or neutral with respect to ground. Be careful!)
The isolation transformer removes that reference to ground, the potential difference exists only between the prongs of the outlet. This is good if you accidentally drop your electric razor into a sink full of water, because there will be no ground current through you - the only current would be from one wet point within the razor to another wet point within the razor.
Isolation transformers are a very important safety feature. Personally, I like them better than ground fault interruptors. The biggest problem with isolation transformers is that making one which will handle the current of a hair dryer or other large (power-wise) appliance requires a lot of heavy iron laminates and copper (expensive).
Fire and Meat. Yummy.