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Need... More... Power...

Posted by michael on from the brownout dept.

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?"

72 of 437 comments (clear)

  1. Well... by JoeBaldwin · · Score: 5, Funny

    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
    1. Re:Well... by another_henry · · Score: 5, Informative
      Incorrect. Fusion reactors can and are being made by amateurs. I'm making one myself at the moment, still in the design stages though :)

      None of these produce any usable power of course.

      --
      "Studies have shown that people who eat peanuts live longer than those who do not eat."
    2. Re:Well... by useosx · · Score: 4, Interesting

      My last apartment both my roommate and I would lose power (and thus our poor boxen would lose data) every time we used the microwave too high or too long. First solution: battery backups (10 bucks each with Staples rebates, g-d bless).

      So no more data loss, but still an annoyance. Then I was stupidly toying with the inside of the light switch for the living room and sparks flew and I blew the circuit. Lucky for us, this led me to discover that there was a 3rd circuit (yes, two circuits was not nearly enough*) for our floor dedicated to a single light bulb that must have been added years after all the other electrical stuff.

      So we ran to Home Depot (g-d bless you overpriced bastards) and back and hacked in a 4-port outlet and we were golden ever since.

      So the moral of the story: when you don't have enough outlets, make more. As a geek you have a instinctive understanding of electricity.

      *The ancient washer and drying in the basement would trip the other circuit if they ran together

    3. Re:Well... by orangesquid · · Score: 3, Interesting

      Our dorm has something like six pairs of recepticles, and we have 11-outlet strips plugged into each and every one to power my many boxen. We're not allowed to use extension cords or piggyback surges strips, so we have to be careful and plan very well...

      I also haven't turned on all the machines at once, because I'm fairly sure it would kill the circuit. I used to have half of these machines spread in my basement, and the load they would generate if they all switched on simultaneously, as the drives and fans were spinning up, was enormous; it would trip the breaker every time.

      --
      --TheOrangeSquid Is it any wonder things seem so awry? We swim in a sea of confusion and don't have to think to survive
    4. Re:Well... by merdark · · Score: 2, Insightful

      So the moral of the story: when you don't have enough outlets, make more. As a geek you have a instinctive understanding of electricity.

      Umm. This is a dangerous suggestion man. Geeks may have an understanding of electricity, but certainly not instinctive. Unless a geek is an engineer or physics major, they probably shouldn't go fooling with building circuitry.

      Then again, if we rid the world of a bunch of geeks, then there will be less competition for those tech jobs eh?

      Weasly idea. Good one.

    5. Re:Well... by Dun+Malg · · Score: 3, Insightful
      Tell me why high-school dropouts can be trusted to build houses, cars, wire complex buildings and run heavy equipment; and PhDs can't figure out how to change a simple wall outlet or check the oil in their car?

      They fancy themselves "intelligent enough" to figure it out on their own and don't expect it to be at all complicated because, after all, uneducated folks do it. They then get stuck in this mindset and won't listen to explainations that sound "complicated" because they've already decided it should be easy. My father, an electrical engineer, was surprised when I showed him my electrician's reference book containing formulas for things like load balancing. He thought, for big jobs, electricians worked off pre-made plans drawn up by someone "educated" who did the calculations for them. I imagine many PhDs think carpenters don't know anything about structural engineering, or that auto mechanics are totally ignorant of mechanical engineering. Ivory-tower arrogance can sometimes work just like thick-headed stupidity.

      --
      If a job's not worth doing, it's not worth doing right.
    6. Re:Well... by Xerithane · · Score: 2, Interesting

      I think the people who are most guilty of this are the "geeks." I see a lot of this stuff happen all the time, where the computer literate attempts to make a simple concept much more difficult in effort to make themselves look good.

      It pisses me off when people choose to explain otherwise simple concepts in very complicated terms. Then, you have to deal with the aftermath, where people are so convinced that computers are a difficult thing.

      I was explaining a rackmount chassis to my girlfriend, and she kept saying, "I don't know anything about computers." I kept telling her, "What I'm talking about has virtually nothing to do with computers. I'm talking about a metal box that you screw to a rack. You know what a closet is, and a shoebox, just listen to what I'm saying."

      Took me forever to break down the computer==difficult wall, but she finally will actually listen, and understand that it really isn't all that difficult.

      --
      Dacels Jewelers can't be trusted.
    7. Re:Well... by UserGoogol · · Score: 2, Funny

      If I have to teach Lambda Calculus in order to tell people how to burn CDs, then so be it.

      --
      "Never attribute to malice that which can be adequately explained by stupidity." -- Hanlon's Razor
  2. Serious answer by Pingular · · Score: 4, Funny

    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)
  3. Nope by Kadmium · · Score: 3, Interesting

    I must say that I don't have enough power in my room. There's only one outlet here and I run a PC, (musical) keyboard, guitar effects kit, DSL modem, clock, etc etc. I have a power strip plugged into another power strip. An interesting side effect is that when I turn on my fan, my USB hub reboots.

    1. Re:Nope by AllUsernamesAreGone · · Score: 2, Insightful

      It's also very dangerous, and may be against your institutions fire or helath and safety rules.

    2. Re:Nope by Mr+Smidge · · Score: 3, Insightful

      Ahh, I had a friend in much the same situation as you last year.. for an entire room, he had only two sockets in the wall. So he promptly daisy-chained together a couple of extension cables to accomodate his desktop computer (with 400W PSU, I might add), monitor, lamps, toaster, kettle, blender, laptop, 150W stereo hifi amp.. The room actually hummed, and similarly to you, the lights in the room would dim whenever he switched on too many things.

      I have 6 plugs to work with (compared to 4 this year), which is just about ample for me with a few extension cables. I had a rather worrying incident last year when my computer would randomly lose power and go off whenever somebody switched on too many appliances downstairs.. But the one time that I switched my computer on in the morning and heard a loud *BANG* (had to replace the PSU after that), I thought again about the power situation.

      Certainly in my case, there really should be more power in rooms.. and not only that but perhaps some safer wiring too - there are a lot of old buildings here that have electrical wiring that's just as old!

    3. Re:Nope by Dr.+Evil · · Score: 3, Insightful

      People say that, but it doesn't make any sense. North American outlets are generally rated and have breakers/fuses for 15A. Breakers on power bars are generally rated for 10A. Plugging a power bar into a power bar into a power bar, and sucking a few watts here and a few watts there with silly fat transformers driving wimpy low-power devices shouldn't cause any problems at all.

      As soon as you hit 10A, your first breaker goes. As soon as you hit 15, the branch circuit breaker goes.

      How is this dangerous?

      Now if you're one of those nuts who's response to blowing a breaker is to put in a bigger breaker, then you'll heat up your wiring in the walls, make the insulation brittle and weak, until some day the insulation cracks, a short appears and that over-rated wire surrounded by dry, warm building materials bursts into flames.

  4. This was an easy Ask Slashdot! by The-Pheon · · Score: 3, Funny
    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?

    Of Course not! I'm a geek :O)

    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?

    yes, of course!

    Dorm rooms and small apartments don't lend themselves to large power generators. Maybe you can get a excercise bike and hook up a line! :)

  5. Good fire prevention policy by SexyKellyOsbourne · · Score: 5, Informative

    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

    1. Re:Good fire prevention policy by Minderbinder106 · · Score: 5, Funny

      Socialist propoganda? Why do socialists care if I put water on a grease fire or if I smoke in bed?

    2. Re:Good fire prevention policy by Jeff+DeMaagd · · Score: 2, Insightful

      I've heard about universities as much as ten years ago banning even just having a refrigerator because the wiring couldn't keep up with every room having a refrigerator.

      Rewiring old buildings is expensive, replacing them even more so, so people had to put up with restrictions. Many of these buildings may be several decades and possibly centuries old, so it may have been a while since the wiring has been given an update.

    3. Re:Good fire prevention policy by Dun+Malg · · Score: 2, Informative
      This doesn't make a lot of sense to me. The whole point of having a circuit breaker/fuse box is to limit the amount of current drawn on a particular circuit. If the current draw gets to be too big for the circuit to handle, then the breaker kicks in and power cuts off. I don't see where having multiple extensions would be any more of a fire hazard.

      Max amp rating on a wall receptacle can be 20A. A cheap Wal-Mart extension cord is rated at 13A. Power 19A worth of load through a 13A cord plugged into a 20A receptacle and you can start a fire without tripping the breaker.

      --
      If a job's not worth doing, it's not worth doing right.
    4. Re:Good fire prevention policy by doktor-hladnjak · · Score: 2, Informative
      I've heard about universities as much as ten years ago banning even just having a refrigerator because the wiring couldn't keep up with every room having a refrigerator.

      I lived in a building like that 5 years ago. I think it was built sometime in the 30s. We were allowed to have refrigerators, but microwaves, toasters, and space heaters were strictly forbidden. You could get in trouble (written up and somehow punished) if any authority figure saw your contraband. However, that didn't really stop a lot of people from not owning a microwave. All that it meant was that people would keep it in their closet and only take it out when they needed to use it.

      My impression of the problem wasn't so much that running a heater or microwave would cause fire or damage to the wiring in your room (there was 1 microwave in the building we all could use), but that if several happened to run at once there would not be enough power coming into the building. The legend we were always threatened with was that if the building loses power, university workers wouldn't come until the next business day to turn it back on!

      Apparently, there's an interesting story about why the building was not significantly upgraded at some earlier point. Originally, it was part of a school for the blind and deaf, which needed major renovation to meet some sort of building codes. Because this was going to be too expensive, the school sold the property to the nearby university and built an entirely new school in another city. The (state) university then (or so the story goes) lobbied the government to *change* the necessary building codes (or at least get some exception), so that the building could be converted into student housing for a lower cost. This combined with the fact that the buildings lie on an earthquake fault...

  6. I have plenty by jevring · · Score: 2, Interesting

    In my dormroom at uu.se, I have plenty of outlets and the are situated in good places around the room, like a 4 socket outlet on the wall next to the TP.

    --
    Move sig!
  7. Easy by clifgriffin · · Score: 5, Funny

    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
  8. Not close to enough power... by RLiegh · · Score: 2, Interesting

    However, I live in a trailer in the middle of the desert. (why? great view and it's cheap.) During the summer I can
    a) run ac and cook
    b) run my computer and ac
    c) run my computer and cook

    but not all three at the same time. (at least, not without having to take trips out to flip breaker switches).

    1. Re:Not close to enough power... by sql*kitten · · Score: 4, Funny

      c) run my computer and cook

      You have an AMD, right?

  9. Dorm room, how about a house? by talieos · · Score: 2, Insightful

    I shopped for a house with electricity in mind, and even then it was difficult. I had to get a house built in the mid eighties or later (true grounds, no aluminum wiring), and I wanted 150 amp or more service.

    Even then I ended up running additional circuits to the garage for tools and lights, basesmet for tools, network, and server. The upstairs room I picked for the desktops had randomly been assigned two different circuts for the wall outlets.

    I don't know what I'd do for power in a 10x15 dorm room, and probably as importantly air conditioning! Plus, at my university, I'd be afraid of the power. The u's electricians seem to have a habit of reversing hot and neutral, and in my machine room a new outlet's ground to neutral was -50 VAC. So power strips wouldn't be enough, you'd need a multimeter as well. heh.

  10. Back when I was at college. by SkiifGeek · · Score: 2, Interesting

    I only had two double point outlets in my 9' X 12' room, and used two surge protected power strips to run everything (6 and 4 port).

    With this, I managed to run a stereo, clock radio, fish tank, desk lights, computer, TV, VCR, powered internal aerial and PlayStation, with sufficient flexibility to be able to run a fan and other various electrical items on the spare ports. This was a pretty standard load for the rooms in the college, although some people had some fairly fancy kit setups (like major tropical fishtanks and home entertainment setups).

    Of more interest is that I managed to fit all my gear into the room for three years (all clothes, toiletries, computer, books and books and books, hundreds of CD's, pictures, all notes and textbooks, software boxes, videos, playstation games, beanbag, guitar, music stand, fishtank, foldaway massage table) and still have room for the bed, desk and student chair and at least 80% of the original floor space still free of crap.

    --
    InfoSec that matters, when it counts.
  11. PC Power for Peripherals by G4from128k · · Score: 2, Insightful

    Because most computer peripherals use either 5 VDC or 12 VDC, why not have a small array of 5V and 12V jacks in the back of PCs? That way, your peripherals can be powered by the PC and automatically turned off when you shut down your machine. This solution would let you dump a bunch of wall-warts and probably be more energy efficient too.

    --
    Two wrongs don't make a right, but three lefts do.
    1. Re:PC Power for Peripherals by gl4ss · · Score: 2, Informative

      well.. usb kind of does this.

      -

      --
      world was created 5 seconds before this post as it is.
    2. Re:PC Power for Peripherals by Ianoo · · Score: 2, Interesting

      You used to be able to get these, actually. I ran my 6V DC speakers off a jack in a free expansion slot for years... it was just a small PCB that connected to a molex inside the machine and had a transformer plus extra resistors/capacitors on it.

      The problem is, I guess, that because so many devices use different voltages, and draw different amounts of power, it might be difficult to provision for every possible device, and you might need a huge PSU. I am not sure whether a normal PSU would be able to supply the PC, my TFT, scanner, PDA cradle and printer without some extra wattage.

  12. LAN Party Power by LordoftheFrings · · Score: 2, Informative

    I have similar problems when I host large LAN parties (IE, over 40 people at a hall). What I have found is that you can work everything out pretty well, and it will reduce problems. In Canada, the standard rating for an electrical circuit is a maximum of 10 amps. When you increase resistance in parallel, you increase the overall amperage. So, you have to watch how many computers you plug into a single circuit. It doesn't matter if it's a new SOCKET, you have to be certain that it's another CIRCUIT. In the US of A, the standard rating is 15 amps (or so I've heard) and so you can run a few more computers. Here in Canada, I find the magic number is 7 computers (that's a random survey of computers, and LANners like to have 400 watt PSUs and tricked out boxes with cold cathodes and the like). I hope that helps. :D

    --
    Canadian Cynic, canadian politics is less boring than you
  13. Outlets are a start.... by Feren · · Score: 5, Informative

    ...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...."

    1. Re:Outlets are a start.... by Ktulu_03 · · Score: 2, Informative

      In our house, we had one circuit that basically powered half the house. One circuit for the garage, two bedrooms, half the living room and half the kitchen. My wife and I each wanted a bedroom for an office, and we needed more juice. I ran a new circuit to each room, bringing it from 2 to 5 outlets each. I also grounded the existing outlets by running a ground wire to the nearest cold water pipe (check with your inspectors to see if that is allowed). If you can't ground existing 2-prong outlets, you can replace them with a GFCI 3-prong outlet, as long as you mark them NG (no ground).

  14. Re:In the closet by silentbozo · · Score: 3, Funny

    Get a cabinet and put your clothes in there. Then take all your electrical appliances and stick them in your closet. If you're worried about sparking, line the closet with tin first.

    A large ABC rated fire extinguisher might also be a good idea...

  15. Re:yeah..they all need more double adapters by An+Economist · · Score: 2, Insightful

    Many dorm rooms can draw only a small amount of power, no matter how many plugs you add. A TV, PC, Seperate Amp, desk light, fridge (popular beer coolant device in college) and have them all on and BOOM! You've blown the fuse for your room which most likely takes out the entire corridor/stairblock. I've experience many power outages from someone overloading the stairblock, seen cables banded between rooms via windows (aerial cables, ethernet to a single connection shared between 20 etc).

    Dorm rooms were wired with only low requirements in mind. These days of consumer electronics overload capacity. RTFA etc etc etc.

  16. What I did for my home office... by opti6600 · · Score: 3, Informative

    This summer we decided that having a 1' deep cable pile over half of my bedroom wasn't a wise idea. So we renovated the old guest bedroom into an office for me. We quickly came to the conclusion that my bedroom was about "-" that close to an electrical fire as-is, so we made sure that there was enough E running to the room for peak power demand of all the systems.

    We currently have one 15-amp circuit (120) and three 20-amp (120) circuits run in here. That's about 9 kW of power if I need it. I strongly recommend with all computing projects that you never, ever, ever scrimp on your electrical budget - it will serve you well.

    Oh yeah, and major points for adding a battery backup - they own.

    -Jordan

  17. Re:Need power strip for surge protection by Anonymous Coward · · Score: 2, Interesting

    Obviously I can't "help" either, but I suppose I can share my home construction story. My father is building a new house, and to deal with the modern day electrical requirements will be ordering an extra 200amp feed from the electrical co, with its own dedicated circuits into the house for the "heavy equipment". Our current house lacks this extra supply, and any time the AC, a vacuum cleaner, or heck, even my monitor turns on, the lights dim (using a vacuum cleaner in my room causes both of my UPSs to switch to battery backup). Just for this, we're also going to run the ceiling lights and fans on a seperate circuit from the outlets. Also high-usage areas (the den) will be fed by more than one circuit (different outlets on different breakers), to handle whatever we throw in there.

  18. Re:More outlets = good by silentbozo · · Score: 4, Insightful

    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.

  19. Re:It's not that complicated... by Lumpy · · Score: 4, Informative

    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.
  20. Re:More outlets = good by silentbozo · · Score: 2, Interesting

    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),

    By this I mean, if you build storage cabinets, put outlets and network jacks in them, in case you want to put in a microserver, or a ReplayTV/Tivo. Extra speaker wires are also nice, in case you want to hook speakers to a central MP3 player, connected to that power and network in your cabinet. Power outlets in cabinets are also handy for keeping battery rechargers out of sight.

    Last bit of advice, locate power outlets/network jacks at least 1.5 feet above desk height if you want to use them with a desk or bookshelf, so that you can still access power/network even with a full set of books on the shelf.

    If this is new constructions, also consider running separate waste lines for toilet vs. washbasin/bath. Certain areas are experimenting with using grey water(ie washbasin water) to flush the toilet in order to conserve drinking water. It wouldn't hurt to have separate lines to have the option of converting in the future if need be.

  21. Re:Need power strip for surge protection by Lumpy · · Score: 5, Informative

    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.
  22. Tsk tsk. Kids today... by lhpineapple · · Score: 2, Funny

    Porn still comes in paper form, you know.

    Zing!

  23. Re:Need power strip for surge protection by silas_moeckel · · Score: 4, Interesting

    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.
  24. Re:In the closet by eyeye · · Score: 3, Informative

    Sounds like they had a weed grow :-)

    --
    Bush and Blair ate my sig!
  25. Computers could take a hint from automotive by Tau+Zero · · Score: 4, Informative
    Because most computer peripherals use either 5 VDC or 12 VDC, why not have a small array of 5V and 12V jacks in the back of PCs?
    To start with, what happens when you run out of jacks in the computer?
    This solution would let you dump a bunch of wall-warts and probably be more energy efficient too.
    Or possibly not. If you need something like 8 volts in a peripheral (to run a CD drive's motors, to give just one example) you couldn't get it easily from +5, so the most likely solution is to use a 3-terminal regulator to get it from +12. This throws away 33% of the power as heat. To get really efficient requires switching power supplies (which I think are great, but they are nowhere near as simple and cheap as a 3-terminal regulator).

    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.
  26. Re:It's not that complicated... by SW6 · · Score: 5, Insightful
    [ on power usage in dorm rooms ]
    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.

  27. Scale back... by supabeast! · · Score: 2, Insightful

    I used to have a room full of computers. My apartment could handle it, at least after I ran CAT 5 along the walls to each of the desks, but after a while it all just got sort of silly, and I decided to start cutting back on the computer lab that was my life.

    First, when a previous employer laid me off, I gave their extra computers that I had been storing (Really, we were storing equipment because the company couldn't afford storage space.) back. When I showed up with the stuff they all thought that I was nuts.

    Then, I stopped doing contract work on weekends. Now I don't ever have tables covered with Sun systems laying around.

    After that, I got sick of dealing with hard disk issues on the Ultra-60 I never used and sold it.

    When my college-student sisters desktop started croaking, I gave her my old 700mhz Athlon machine.

    After I finally gave up on trying to keep driver and Direct X versions compatible with my games, I stopped using my Windows box for anything but the occasional blackboad.com login, so it sits cold all day.

    Most recently, a storm finally wiped out my poor little firewall, after four years of R2D2-like service, and I haven't fixed or replaced her yet.

    So now I'm down to just using my iBook most of the time. Makes life nice and simple, and honestly, I don't really mind the silence that comes with all of those other computers being turned OFF.

  28. Use less? (Slightly OT) by saynte · · Score: 2, Insightful
    There are quite a few people here saying that they don't have enough outlets to run all of their "stuff". While this is a valid point, I think maybe that there is another problem here: too much luxury. I'm not going to say that people don't have a right to their electricity, or that they can't run gadget A, or appliance B. I just think that, if when you take a look at all the things you have, you probably don't really need all of it. Now I'm speaking with regards to dorm-rooms here, not so much apartment buildings where less is provided for you.

    Why don't people just either

    a) not bring so much stuff to school (where in theory you should be working most of the time anyway)

    or b) just UNPLUG one thing, then plug another in! (you don't really need to run everything concurrently)

    To me at least, it just seems that people are starting to jump to the "how do I expand my current limits" solution, when maybe the "how do I conserve power" solution might be better in some situations. I am not saying this holds true for everyone, some people have to be able to watch a video and decompose the effect of the background on the overall composition of the..(well you get the idea), but in GENERAL conservation should be used before expansion.

  29. Rewire to 220 volts by morcheeba · · Score: 2, Funny

    You can double the amount of power that you can use in your room by simply switching to 220 volts. It doesn't require a transformer to do this; just wire your outlets the same way a 220v dryer is wired.

    A friend had a dorm mate that had brought a 220v stereo from overseas... they found that half the room was on one 110v circuit and that the other half was on another. So, they connected the stereo to the "hot"s of each circuit, and they had 220 volts total. Or something close enough.

    Ok, it's not to code at all and is dangerous because some appliances (like lamps and toasters) will have electrified enclosures. But, it would work as long as no appliances touched each other, you, your dog, or a real ground.

    --
    HIV Crosses Species Barrier... into Muppets
    1. Re:Rewire to 220 volts by morcheeba · · Score: 2, Interesting

      I guess I confused the ways of implementing it...

      The way the friend wired the stereo wouldn't get you more power in the room; you get double the power to your device, but you also use double the outlets.

      But, if you were to go back to the breaker box and rewire your outlets there, you'd get double the voltage at each outlet.. the amperage won't go down (unless you plan on rewiring the wires in the wall and replacing the sockets), so you'll have double the power.

      True, countries that use 220v can get away with thinner wires to deliver the same amount of power.

      --
      HIV Crosses Species Barrier... into Muppets
    2. Re:Rewire to 220 volts by adrianbaugh · · Score: 2, Interesting

      thinner wire

      Also potentially lower risk of fire in various situations.

      --
      "'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
      - JRR Tolkien.
  30. I don't think the students are to blame by Hoplite3 · · Score: 2, Insightful

    "It looks like Circuit City in some of those rooms," said Dan Bertsos, director of residence services at Wright State University near Dayton, Ohio.

    And also:

    They power a color TV, stereo, compact disc and DVD players, video game player, desktop computer and laptop, printer, scanner, refrigerator, microwave and two fans. Then there are rechargers for a cell phone, hand-held computer, camera, electric razor and toothbrush.

    Yeah, but I bet Dan has all of these things at home too. Most of these new appliances are a result of college policies and planning. The computer is obvious. It is at minimum the new typewriter. The printer and scanner come along when the college doesn't provide these services in a convenient place or charges too much for them. The stereo has been around for a while in dorm rooms. You need one because the shitty radio isn't going to cut it. The TV and the DVD player are in each room because there's no communal space for reasonably sized groups (4-8 students). If they had a place with their friends, these things could live out in some sort of small living room. The microwave and refrigerator are in response to colleges jacking up board costs to pay for fundraising activities (a very common practice). They are also not new: my mom was boiling water on a hotplate in here dorm room -- much less safe than a microwave. Again, some communal space could reduce the number of microwaves a fridges.

    Most dorms try to provide communal space in living rooms that are public to some 12-20 students. This is far too large. There's too much sharing of responsibility for the accidents in the microwave to ever get cleaned or for food in the fridge to be safe from hungry fingers. You need a space that the small group feels ownership over.

    --
    Use the Firehose to mod down Second Life stories!
  31. A lot of electronics don't use too much power... by Jearil · · Score: 2, Interesting

    I had a situation at my school last year where our power kept going off because our circut was overloading and the breaker would go off. We learned how to reset it from the box that was down the hall, but it was really annoying that it kept going off. What was stranger was it never had this problem before, so finally we had the maintence department of the school come up and check it out and I learned a bit about how much power devices consume.

    Our room was one of 3 doubles set up on the same circut. We were the only ones around, so we couldn't do much about the other rooms power, but we could look at ours. The circuts cut after 20 amps. When we turned everything on in our room, the circut breaker went off and broke the circut, but we found out that it wasn't our stuff causing me majority of the problem. We had in the room 3 computers, 4 monitors, 2 TV's, 2 Xboxes, 3 lamps, 2 alarm clocks, 2 phones, 2 speaker systems, 1 sperate stereo, a dozen accessories for various computers (printers, scanners... etc). and a few other things that I can't remember.

    When we had all of our stuf off, the breaker was still reporting 11 amps being drawn from the other rooms. He went into one and found an illegal (per college rules anyway) space heater in there on with no one around. He turned just that off and we were down to 2 amps being drawn. After turning all of our stuff back on, it went up to 12.

    One space heater was using almost as much power as 2 people's worth of electronics. Moral of the story: don't use space heaters in college dorms 'cause power outages every 30 mins suck.

  32. Try the traditional approach by chunkwhite86 · · Score: 4, Funny

    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.
  33. Re:It's not that complicated... by Anonymous Coward · · Score: 2, Informative
    he is right. from 350 to 550 watts for a computer, tower/minitower model. this is not the low end crap that most students have, this is talking about geeks here.


    No, actually, he's/you're wrong. My Antec power supply is rated at 400 watts, and running two optical drives, raid 5, an additional hard drive, and over a dozen fans, and my line load at the outlet is no where near 400 watts last time I checked. Has been over a year since I checked, but I haven't changed the setup since then either.

    This also has been covered in articles where cost of running a computer has been discussed, and is also covered on some electrical utility web sites. Electrical consumption is rarely even close to what the power supply is rated at. Usually it is much less, often less than half.

    This also often applies to stereos and other electrical items.
  34. Darn adapters by owlstead · · Score: 2, Interesting
    I do not need more power; I need more outlets. These two are not the same. Currently my whole room has been filled with adapters; get ready for the list.
    • Mobile phone
    • DECT phone
    • Printer
    • Scanner
    • Computer speaker set
    • USB HUB
    • Laptop
    • VIA EPIA external power adapter (ok, in design, so leave it out for now)
    • MIDI keyboard
    • Switch
    • ADSL modem
    • 54Mbit wireless access point
    This is all excluding the normal devices (which I will leave out).

    Question to you techies out there. Is it not possible to device a standard for these kind of devices? It would be nice to have an (upgradable) 12 V DC adapter in the house. Currently almost none of the adapters take just one outlet. Note that I am on 230V since I live in NL (europe). Not that that matters too much, I expect you are experiencing the same problem.
  35. Own Less Stuff by deaddeng · · Score: 2

    Or leave it at home. Do you really *need* a TV, PC, laptop, 500W sound system, dvd player, PS2, Xbox, etc. in your dorm room?

    Put a TV+FM tuner card and a DVD in your PC and a decent sound card. Get better-quality 5.1/6.1 surround speakers for the PC. One device replaces many, and with an LCD uses little power.

    You'll still *need* the PS2/Xbox I suppose.

    --
    --- .085 as cool; proving that a little knowledge is dangerous
  36. Underpowered dorms GOOD! by joe170 · · Score: 5, Funny

    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!

  37. Just do the math by darco · · Score: 5, Informative

    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
  38. Power Consumption by BigBlockMopar · · Score: 5, Informative

    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:

    • all those hours of inactivity are turned into exercise
    • makes watching TV a lot more work than doing the studying you really should be doing, so your marks will improve
    • saves you from watching The Matrix for the 700th time when you could be doing more productive things like drinking beer with friends

    I do have to wonder about how bad this dorm room power crisis really is. Let's consider appliances with realistic maximum power consumptions:

    • Computer - 350 watts
    • Monitor - 250 watts
    • Computer speakers - 50 watts (note that this is less than the output "ratings" from the marketing department - your "350W" computer speakers must be violating the laws of conservation of energy)
    • Laser printer - 300 watts
    • Wall-warts for PDA, cellphone, clock-radio, small switched hub or router - 30 watts total
    • Boom box - 50 watts (see Computer Speakers)
    • TV set - 250 watts
    • VCR/DVD player - 50 watts
    • Beer fridge - 300 watts
    • Lights over desk, etc - 200 watts

    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:

    • Computer - 350 watts
    • Monitor - space-saving LCD - 60 watts
    • Computer speakers - 50 watts
    • Laser printer - 300 watts
    • Wall-warts for PDA, cellphone, clock-radio, small switched hub or router - 30 watts total
    • Boom box - play MP3/Ogg/CDs from computer - 0 watts
    • TV set - video card with TV features, preferably not ATI because their software sucks - 0 watts
    • VCR/DVD player - play DVD on computer, and if you absolutely have to rip some video off-air, do it with the computer - 0 watts
    • Beer fridge - 300 watts
    • Lights over desk, etc - 200 watts

    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.
    1. Re:Power Consumption by swankypimp · · Score: 2, Funny
      where are you gonna park 2+ computers in your dorm room and still have a flat work surface to do your math homework?

      It's called The Library. Not only are there desks there, but you don't have to block out the ambient noise of three idling computers in an enclosed concrete 10' by 8' space.

      --

      --All your stolen base are belong to Rickey Henderson
    2. Re:Power Consumption by weiyuent · · Score: 2, Informative

      Note for comparison that various experts have estimated Lance Armstrong's sustained power output to be about 450W. Mine (with my fit but still typically geek-like physique) is more on the order of 180W, as measured recently on an ergometer. Elite sprinters, of course, put out far more but for only a brief interval.

  39. Renovations - electrical and gray water by BigBlockMopar · · Score: 3, Informative

    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.

    Agreed. But there's still more to it than that.

    Surge suppressors on the power entry, just after the main switch. *Large* breaker box.

    And if you're building the house - or doing extensive work involving the removal of lots of drywall anyway - rewire the whole house. Build it to commercial specs, even if your residential requirements are lighter.

    My suggestion is to use conduit for all wiring, and make sure that you put in extra conduit all over the place so that you can fish network and phone cables into any room as required. Put each duplex outlet on a separate 15A circuit (20A circuits are against code in residences in most jurisdictions). GFI outlets aren't just for bathrooms - they're not very expensive, so put them everywhere - they can save your life and your electronics from damage (say your stereo has a ground leak and you connect it to your computer). And make sure that you have an outlet at least every 10 feet in every room.

    While you're doing all that, of course, you should be installing a residential sprinkler system. (Why? Sprinklers massively improve the fire safety of a house or commercial building. And it's a lot easier to clean up water damage than fire damage.) The reduction in your insurance rates over a few years might well pay for your entire renovation costs, and talk to your insurance company about the fact that the building is wired to commercial standards for another potential savings.

    Other things to consider: While you've got the house apart, insulate the piss out of it, whether you're in a warm or cold climate.

    You might also want to install a gray water system for the toilets. It's against code in my jurisdiction, but I don't really care because it's a good idea. The premise is simple: my toilet is almost 50 years old. It's not one of those stupid "water-efficient" toilets that takes 6 flushes to get rid of dark matter. And I don't like urinating in perfectly clean water - there's no point. So I put a 55 gallon drum in the basement. The bathtub U-trap (unscrew the washout nipple and find a piece of pipe of the same thread, make sure you still have a bend in the hose for a three-way U-trap) and washing machine now drain into the barrel. Using bleach in a cotton white cycle not only keeps your shirts blindingly white, but also keeps algae out of the barrel. Near the top of the barrel is an overflow pipe which takes excess stored water to the drain. A burglar alarm magnetic switch on the toilet's float now controls a relay which turns on a small pump. Gray water is pumped through a small hose up into the toilet tank, using a fountain pump with 15 feet of head.

    Since I live in a cold climate and like hot showers, not only am I reclaiming the water, but I'm also reclaiming the heat. The water in the barrel cools down slowly, releasing its heat into the house. Saves me over $200 a year in heat and water costs.

    A fringe benefit is that warm soapy water in the toilet dissolves stuff better than cold tap water, so the toilet doesn't need to be cleaned as often.

    --
    Fire and Meat. Yummy.
    1. Re:Renovations - electrical and gray water by Anonymous Coward · · Score: 2, Funny

      Ok, so you've got bleach in the tank...

      Bleachy water pumped back into the toilet bowl...

      You go for a massive shit...

      While dropping a huge depth-charge, you get bleachy splash-back on your ringpiece...

      I'm not convinced...

  40. Re:Alternative to high-voltage AC outlets? by tim_mathews · · Score: 2, Insightful
    OK, let's have an example of this. Say you need 100A @ 12V for all your stuff. This isn't an unreasonable number if you have a couple of computers, an LCD or two, a heater(?!), that's crazy, but I'll bite. To get that to run 500' (again, not an unreasonable number if it has to come from some central supply in the building), you need 1000' of wire. Remember we have to make a return trip. You want 12V to be available at full load. Which means you'll need a regulator in your room (minor detail really).

    To carry 100A, engineers recommend at least #4 wire (0.232" dia.) so that it doesn't get too hot. As we will see in this example #2/0 (two-aught) (0.414" dia) or bigger is a better choice.

    The resistance of #2/0 is 0.15ohms/1000ft. Our run is 1000 feet (500 each way). For that length run at 100A, the voltage drop is 15.4V, so to get 12V we need a powersupply that outputs at least 27.4V. Our efficiency here is 43.79%. That sucks!

    We'll try again with a bigger wire. 4/0 (0.552" dia) this time. The resistance is 0.049ohm/1000feet. Now we only need a 21.8V power supply and our efficiency is up to 55%. This still sucks compared to AC. Now imagine wiring a whole building like this. Perhaps we need 10,000A of DC power, we'd have to give up using copper and go to something with a lower resistance (silver for example). At $5.36/oz (current market price) that's just not feasable.

    Sorry you loose.

  41. Re:I'm a University of Wisconsin Madison student.. by Beowulf_Boy · · Score: 4, Insightful

    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.

  42. Extension cords and current limits by rcw-home · · Score: 2, Informative
    Can you really?

    A 13 amp extension cord is usually 16-gauge, sometimes 14-gauge for the longer ones.

    19 amps running through 16-gauge wire (4.094 ohms per 1000') converts about 1.48 watts per foot to heat.

    You'd have to run this extension cord through some amazingly perfect thermal insulation (carpeting won't do it) before anything could get to flashpoint.

    Standard amperage limits are based off acceptable voltage drops, not heating.

    1. Re:Extension cords and current limits by Dun+Malg · · Score: 2, Interesting
      Standard amperage limits are based off acceptable voltage drops, not heating.

      True. I was leaning more towards a point based on susceptibility to damage of cheaper cords; I've never seen a 12ga extension short out from being closed in a door. I have, however, seen cheap extension cords heat up enough soften the insulation. Stick it under a metal table leg and an extension cord with soft insulation doesn't HAVE to heat up to flashpoint to cause a fire. Besides, citing what the gauge of a cheap cord should be doesn't mean much if the conductors are undersized for their stated rating. Optimal conditions are great for electrical theory, but in the field you sometimes can't even trust your wiggy or your multimeter.

      --
      If a job's not worth doing, it's not worth doing right.
  43. Those Pesky Ungrounded Outlets in Bathrooms by BigBlockMopar · · Score: 4, Informative

    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.
    1. Re:Those Pesky Ungrounded Outlets in Bathrooms by BigBlockMopar · · Score: 2, Informative

      " The wide blade is supposed to be connected to neutral, the narrow blade is supposed to be connected to hot."
      then wouldn't you only get 1/2 phase?

      Nope.

      Neutral is tied to ground, it serves as a reference point. The hot side alternates between +120V and -120V with respect to neutral.

      It's like the body in your car - it's "ground", and the +12V from the battery is referenced to it. In the case of a car, it's not for safety reasons, but for convenience - to power a light, all you need to do is run one wire from the positive terminal of the battery to the light, and then connect the light's other terminal to the body.

      If you were to reverse the battery in your car (connect the positive terminal to ground), then the -12V would be referenced to ground. Current would still flow quite happily - although it would destroy all electronic devices in your car, exactly the same as accidentally putting the batteries into your Walkman backwards.

      On ships, they don't reference 120V AC power to ground, they reference it to the center tap of the distribution transformer. In other words, with respect to ground (ie. connecting your Fluke 77 DMM to the ship's steel), you have +60V and -60V at each blade during one half of the cycle, then -60V and +60V at each blade during the other half of the cycle. Of course, between the blades, the difference is still 120V. This system is used on ships because rather than having a 50% chance of a potentially lethal shock if you accidentally touch a broken wire, you have a 100% chance of a significantly less dangerous shock. In a moist environment, this is a good idea.

      Note also for the sake of clarity that I've oversimplified a few things - RMS voltages from wall sockets, charging system voltages in cars tend to be around 13.8V, etc.

      --
      Fire and Meat. Yummy.
  44. Re:Nit: all single phase by calidoscope · · Score: 2, Informative
    The American residential electrical service traces its roots to Edison's Pearl Street station in 1882 - DC at plus/minus 120V. Single phase service simply replaces the +/- with 0/180 degree phases. The 110/220, 115/230 and 120/240 refer to the min/medium/max expected voltages in a residence.

    In the US, three phase installations tend to be 120/208 wye connected for office and light industrial and 460 delta connected for the heavier stuff. In Sweden, virtually all houses have three phase delivery, 220/390.

    There were some two phase systems in the early days of the electric power industry, typically these are where you need three conductors and where on conductor is at ground potential. The turbo-electric plant on the Lexington and Saratoga (CVA-2 and CVA-3) were two phase since the hull served as the grounded conductor.

    As for frequency, the US standardized on 60 Hz as a reaction to Europe standardizing on 50 Hz, although Southern California Edison didn't make the switch until 1947/48. Some communities had 25 Hz power, and one had 133 Hz. DC was available in some cities until very recently. Homes on windmills in the 30's and 40's usually had 32V power which was also used by the majority of US RR passenger cars.

    --
    A Shadeless room is a brighter room.
  45. Postsmart Apartments by eabell · · Score: 2, Interesting

    Post Properties are big when I live in Atlanta. I admit, when I was moving the lure of their PostSmart apartments was fairly high.

    Basically, their new apartments are built wired to support home networking (wired), surround sound, and multiple phone lines. The outlets, however, were fairly ugly -- huge wall units like you'd see in a business. But there were network drops in every room and plenty of outlets and, most appealing to me, audio wires for surround sound and multiple speakers. I hate wiring for surround sound in the living room every time I change apartments. Here, you just plugged into the wall behind the TV, and then the wires came out the other side of the room and even on the patio.

    Ultimately, despite the high geek factor, I didn't go with the properties with this feature. The rent was pretty steep compared to what I could get elsewhere, and wireless was already on the scene so I figured the networking wouldn't be too crucial. I'm also wondering if they opened the electrical system to support such a wired household. Hrm. I haven't heard of any burning down lately, I suppose...

  46. No Holes! by AndyCanfield · · Score: 2, Informative

    Standard construction in Thailand, where I live, has one [1] two[2]-holed electrical outlet per room, right next to the light switch by the door. Lots and lots of extension cords. In our bedroom the previous tenant had an air conditioner; we spliced the leftover power wires to an extension cord to create an outlet on that side of the room. Unless you have an electrician install the wiring, and watch him carefully, nothing is grounded, even if it's got three holes.

  47. Enough? by lelnet · · Score: 2, Informative

    Well, mine does have _enough_ of them...but they're almost all _on the wrong side_. (The side with lots of outlets, including the cable TV feed and all the phone jacks, is the one which hosts the sofa and the lamps, while the one with all the computer and A/V hardware that so desperately wants to be fed power and bits has a measly two wall plates for power. Due to the odd geometry of the place, reversing the furniture arrangement would make it impossible to walk.)

    I solve it by running long cables across the room, held above head height by wrapping them around the rafters (it's a loft).