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Displaying poll results.
1-2: Better safe than sorry
298 votes / 0%
3-4: Power strips are OK, right
  4120 votes / 13%
5-8: Make that two power strips
  13769 votes / 44%
9-16: Only a little smoke coming out
  7201 votes / 23%
>16: Waiting for the big bang
  5093 votes / 16%
All my stuff runs on batteries your insensitive clod
  644 votes / 2%
31125 total votes.
[ Voting Booth | Other Polls | Back Home ]
  • Don't complain about lack of options. You've got to pick a few when you do multiple choice. Those are the breaks.
  • Feel free to suggest poll ideas if you're feeling creative. I'd strongly suggest reading the past polls first.
  • This whole thing is wildly inaccurate. Rounding errors, ballot stuffers, dynamic IPs, firewalls. If you're using these numbers to do anything important, you're insane.
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  • I haven't burned out yet in a house with limited outlets (this time). My last house, I could barely run a laptop off of one outlet.
  • 230V 16A (Score:3, Interesting)

    by Gnutte (907952) on Tuesday February 08, 2011 @09:49AM (#35136822)
    Can power quite a lot of equipment. 16+ should not be a big issue in Europe...
    • Jesus. That's on one circuit? Did the electrician look at you funny when you asked for that?
      • by Gnutte (907952)
        Not really, in Sweden 16A groups are quite standard in comercial buildings like offices. I modern homes it's usually 10A. But mind you that the cables are quite thick.
        • In the uk a standard ring main can carry 30 amps at 230 volts if your running a power strip then the plug is rated at 13 amps roughly a 3kw load. Cookers Showers immersion heaters have dedicated wiring.

          • by AmiMoJo (196126)

            You have to be careful though. Because we use a very large ring main you could easily exceed that with a few electric heaters. Also some people do stupid things like spurs-off-spurs or wiring into the lighting ring.

            But yeah, generally speaking our sockets are pretty much the best in the world IMHO. They are very safe and the plugs sit in the solidly. You can run a hell of a lot of stuff off them too.

      • by ellep (1746938)
        Yes, in mainland Europe it is quite common to have only 230V 16A circuits. And each proper extension cord can handle 16A, so chaining them is not really a problem unless the total load is over 3,6KW Reminds me of when we had an American over at our company and he asked for an extension cord. He looked really shocked when we gave him one.
      • by scsirob (246572)

        This is standard in most European countries. A single 230V circuit is fused for 16A, while regular homes are fused for 25A or 35A for all circuits together. So you are not expected to use 6 circuits and all at 16A.

        I have 3-phase 230V 3x 25A at home. This drives 12 circuits (3x 4) fused at 16A each. If I want, I can get a 400V 3-phase circuit for heavy equipment.

        • by afidel (530433)
          400V or 480V? Here in the US my UPS's are fed at 480V which is pretty typical for mid to large size setups.
      • by Achra (846023)
        Not all countries have the same electrical standards as the united states (In fact MOST of them don't)... I'm not sure off hand which other countries carry 115v 60hz power (maybe japan?), but certainly most of europe is on some version of 220-250v 50hz. I believe that Nikola Tesla pretty much dictated the US's 115v 60hz.. I assume that other countries might have based their electricity on whatever was simplest to implement.
    • by afidel (530433)
      Try an L21-30 connector, max power available is almost 9kva, it can power a LOT of equipment. I've powered 16 blade servers and 20 1U servers off a single connector (with a second for redundancy of course).
  • but I'm talking about mostly wall wart type power supplies, into one 240v* 13a UK 3-pin socket (via a couple of power strips). One UK socket would take 10 full PCs, never mind wall warts.

    *I know that we're officially on 230v European standard mains now; but in reality it's normally 240v or more at the socket. Whenever I've measured the voltage it's been around 250v. I guess legacy heavy power transformers (In the UK the last step-down transformer is usually neighbourhood level, not on a pole serving a coup

    • by Carewolf (581105)

      230V is only an approximation. In Denmark it used to 220V, and other places it used to 250V. I think all you are guaranteed with the European "standard" is somewhere between 210-250V

      2000->3000W should enough for most situation. Otherwise you just need to find the high-power 380V outlet used for ovens, or the high-amp outlet used for audio-equipment. And what is up with the risk of fire or explosion?, has no one heard of government mandated fuses, and minimum requirements to cables going into power outlet

      • by tomhudson (43916)

        And what is up with the risk of fire or explosion?, has no one heard of government mandated fuses, and minimum requirements to cables going into power outlets? Tsk. tsk.

        Haven't you heard? Your motherboard is the fuse. It will protect your house by taking out your cpu, power supply, ram, and drives. If that doesn't work, your power supply can do the same, taking out your cpu, ram, motherboard and drives.

        Redundant protection. Because it's not "bad capacitors", it's a feature!

      • by afidel (530433)
        Yeah my 480V nominal feed will be up around 495V during the summer when the utility is trying to compensate for peak load. Right now during the winter it's at only 487V.
    • by xaxa (988988) on Tuesday February 08, 2011 @10:44AM (#35137598)

      As far as I know, it's very difficult to cause a dangerous situation with UK wiring, unless you've got some dodgy imported stuff or have some bad DIY. The fuse in the plug of the power strip will prevent you overloading the socket.

      However, I've seen travel adaptors sold for use by Americans in the UK without a fuse (or covers over the terminals, or plastic sheaths around the base of the prongs). This is dangerous, since the circuit breaker is usually 30A... a short circuit in an appliance with a US plug connected to one of these adaptors could draw 30A, until the appliance's wire catches fire. (A travel adaptor sold in the UK for use by Americans would have a 3-5A fuse in the adaptor.)

      Of course, none of this would be necessary if the circuit breaker was, say, 15A. Although then you'd have to have a more substantial cable for your laptop charger and table lamp.

  • Wattage (Score:5, Insightful)

    by ath1901 (1570281) on Tuesday February 08, 2011 @09:54AM (#35136874)

    I'm more concerned about the total wattage than the number of items. I don't mind plugging in 16+ mobile phone chargers in the same outlet but I try not to plug in more than one vaccuum cleaner.

    • Re:Wattage (Score:5, Funny)

      by Anonymous Coward on Tuesday February 08, 2011 @10:11AM (#35137106)

      I try not to plug in more than one vaccuum cleaner.

      Do you have to struggle to resist the urge to plug in more than one vacuum from the same outlet?
      I'm trying to picture the situation where I'd be tempted to do that, and all I can come up with is defense against a horde of oncoming zombie cats. They aren't afraid of fire, but I bet the survivors of that onslaught are people who had a) more than one vacuum and b) the restraint not to plug them into one outlet and blow it.

      • Re:Wattage (Score:4, Informative)

        by tomhudson (43916) <barbara...hudson@@@barbara-hudson...com> on Tuesday February 08, 2011 @11:30AM (#35138196) Journal
        Breakers or fuses serve more than one wall outlet. Plugging stuff into two separate outlets isn't enough - you need to make sure they're on different lines so you don't exceed the total rated amperage.

        A window-mounted air conditioner and a hair dryer can easily exceed the 15 amp maximum for a 120v circuit.

      • by vlm (69642)

        Do you have to struggle to resist the urge to plug in more than one vacuum from the same outlet?
        I'm trying to picture the situation where I'd be tempted to do that, and all I can come up with is defense against a horde of oncoming zombie cats.

        Hang out with a woodworker for awhile, try a radial arm saw cutting bookcase shelves to length while youthful assistant tidys up the shelves on the "stationary belt sander thingy". The machines had dedicated circuits, but starting both shop vacs at the same time on the same outlet didn't work so well. Thankfully overhead lighting was on a separate circuit.

    • by 6Yankee (597075)
      If all your wives are talking on the phone instead of doing housework, you're doing it wrong :D
  • I'm assuming we're talking about mains cabling here and not, say, a pair of 415V commando sockets providing redundant power to racks full of switches/routers/servers/NAS appliances, because in that case I've done 42 devices per socket on numerous occassions... I've also quite happily run a sizeable bank of recharging stations for things like mobile phones and PMR devices off a single 240V, 13A socket, no problems.
    For more typical home/office use I tend to stick to no more than 75% of the max fused curre
  • Most all of my stuff is low-power, so powering a metric buttload (1.2X an English buttload) of devices from a single outlet is no biggie. I invariably need more places to plug things in than the current capacity of the outlet can handle.
  • Most powerstrips I've seen have 6 outlets, and that's pretty much exactly what I use.
  • 5 - 8 sounds like a single power strip to me.
  • by dindi (78034)

    I thought that you matched the breaker to the cables it supports, then if an overload happens, it just shuts down instead of causing a fire.....

    But in costa rica we are happy if the grounding is existent in a home... Freaks me out to see water heaters with the grounding cable dangling unconnected:(

    • by NevarMore (248971)

      Freaks me out to see water heaters with the grounding cable dangling unconnected:(

      Its not ideal, but you should be able to connect that ground cable to the cold water pipe. Its a piece of conductive material that runs into the ground. Its not ideal, but it'll work.

      • by vlm (69642)

        Its not ideal, but you should be able to connect that ground cable to the cold water pipe. Its a piece of conductive material that runs into the ground. Its not ideal, but it'll work.

        Unless they're doing the ultra-trendy PEX pipe thing.

  • I have over ten devices running on one outlet in my entertainment center, but I don't think all of them have ever been in use simultaneously. After all, it's pointless to power up three different gaming consoles, a DVD/VCR combo, and a DVR, when they're all connected to the same TV.
  • by Ellis D. Tripp (755736) on Tuesday February 08, 2011 @10:31AM (#35137396) Homepage

    Had to power an entire building from a single outlet during some renovation work a few years ago.

    Of course, it was a 3 phase 200A 480V 3 phase receptacle on the side of a trailer-mounted generator, but the question didn't specify what kind of "outlet" you needed to use...

  • The fuse in the power strip's plug will blow if the load is too high.

    • by MrNemesis (587188) on Tuesday February 08, 2011 @11:06AM (#35137926) Homepage Journal

      ...unless you've had the cowboys in.

      First proper company I worked for hired me because they were firing their (incompetent and expensive) outsourced IT and getting an in-house team. Most of the company servers were run out of a colo facility a couple of miles away but the head office ran half a dozen servers in a 48U rack in what was essentially an oversized broom cupboard.

      Crowning moment of stupidity was when we discovered that, instead of installing the extra mains rail like they'd been paid to do, they'd instead used a daisy chain of gangplugs inside the cable ducting. One of these had obviously blown from the load previously - the plastic all around the socket was melted, as was the plastic insulation on the plug prongs itself. Why? It was a cheap gangplug (I doubt it even confirmed to British electrical standards, the plastic was exceptionally brittle) that was only rated for 3A (i.e. capable of delivering 720W max), but had been refitted with a 13A fuse (allowing 3.1kW) after the first fuse had blown (there were still brown burn marks on the fuse clips). It was warm, verging on hot, to the touch when I found it. Even more outrageous was the fact that the PAT people who'd been in two weeks previously hadn't noticed this error.

      With proper cabling though, it's easy to run a dozen boxes off a regular 13A outlet... just woe betide someone plugging in the 3kW kettle or the 2kW laser printer at the same time.

  • And certainly not yours! I am a free insensitive clod!
  • by berryjw (1071694) on Tuesday February 08, 2011 @10:58AM (#35137808)
    I've run up to 30 MacBooks off a single outlet/circuit while imaging. Admittedly, that's seriously pushing it, 25 is much more reasonable. The first rounds were done on folding tables in a garage, though, and we were running forty at a time on two 15 amp 110v circuits, over extension cords and daisy-chained strips to all the machines, the switches, and the xserve running the mess. Yes, it made me a bit twitchy, but we didn't melt anything.
  • - Laptop
    - Two lights (CFL so not much energy, probably 40W combined, one was 120W equiv.)
    - Router
    - Alarm clock
    - Cable modem
    - USB hub
    - Fan
    - Air conditioner
    Some other stuff, I forget now...
    • by Zumbs (1241138)

      At my previous flat, I had the following plugged into one outlet:

      • Refrigirator
      • Gamer PC
      • Monitor
      • Halogen lamp
      • Cable Modem
      • Router
      • Printer
      • Hotplate
      • Phone Charger
  • Plug 1 - 1 UPS, 1 low-power scale, 1 strip with 4 low power devices and 13w CFL reading light
    UPS: - 2 strips with 2 others plugged into them. The strips have computer, monitor,
    2 disc arrays, router, 5 external drives, and laptop docking station

    So far, the system has survived all short term power failures (under 15 minutes). Longer term ones
    cause the system to automatically shut down.
    • by vlm (69642)

      Plug 1 - 1 UPS, 1 low-power scale, 1 strip with 4 low power devices and 13w CFL reading light

      UPS: - 2 strips with 2 others plugged into them. The strips have computer, monitor,

      2 disc arrays, router, 5 external drives, and laptop docking station

      So far, the system has survived all short term power failures (under 15 minutes). Longer term ones

      cause the system to automatically shut down.

      I have seen hilarity when a very large UPS and a large (for the time) compute cluster were installed on a circuit that could only supply enough power to run either the cluster OR run the beefy UPS while the UPS was in drained battery charge mode. Hilarious, I tell you. This was a telco facility BTW so we're talking A and B -48 VDC bus and separate "rectifier" "charger" units.

      • by woboyle (1044168)
        :-) Well, I don't think I am going to rewire my house... The only time we have tripped a circuit breaker is when we tried to run both the microwave and expresso machine (in heating mode) or vacuum cleaner on the same circuit at the same time. The MW is 1500 watts. I think the expresso machine is about 1000 watts when then heating element is on...
  • In my bedroom a power strip runs from the wall (occasionally I plug things into here), then My UPS plugs into that (I know, it could trip unnecesarily, I'll change it sometime) through a kill-a-watt. Then a desktop power controller (box with a buncha switches for cutting power to different components) plugs into the UPS, and my gaming desktop, monitor, and 2 PDA chargers plug into that.

  • by LMacG (118321)

    220, 221, whatever it takes.

  • Who's got a string of Christmas lights less than 16 bulbs/L.E.D.s long? Or a modern electronic device with fewer than 16 ICs?
  • Was only open for Xmas shopping season, closed before the New Year hit. It wasn't a large space, but we only had two outlets and a large number of cheezy knickknacks that displayed much better when you could plug them in. When we requested more be installed the Mall told us it would take about three months to get the work done, which basically was the majority of the time the store was going to be open. I ended up buying a series of extension cords and power strips and hoped the whole setup didn't burn d

  • It's not about how many devices, it's about power draw.
    Desktop: 365 W
    Laptop: 65 W
    3x External HD: 36 W total
    Router: 12 W

    total: 478 W. It's just not that much.

    • Yeah, the number of devices hardly matters -- a hundred 5 Watt wall warts is no big deal, but a hundred 1500 Watt electric kettles...
  • So where else am I supposed to string 3 powerstrips with 6 to 8 outlets on each to for all of my electronic gadgets? And this isn't even covering the extra monitors and speakers for the extra PC's.

  • by idontgno (624372) on Tuesday February 08, 2011 @12:22PM (#35138942) Journal

    The current loop generates infinite free electricity.

    Problem, electrical engineers?

    • by geekoid (135745)

      It's true. You will, forever, maintain a constant 0 volts.

    • by timster (32400)

      If you want to confuse a bunch of UPSes plug about 4-5 of them into each other in a circle.

      Disclaimer: don't.

  • I have plenty of power strips with 8 or 10 sockets laying around. I'd never hook them up to each other, but if I'm setting up some friends for a LAN, we can easily get 8-10 devices (mostly laptops and routers) plugged into a single strip. 8-10 (or more) devices isn't that heavy of a load, for many electronics. We don't have crappy wiring, and we don't buy crappy power strips.

    That doesn't mean I'm going to plug the fridge or a heater into one, though.

  • Powers two 500 VA UPSs, which in turn power & protect two PCs (each with monitor & speakers), a departmental laser printer, a small NAS and 3 network devices. With the one remaining open outlet, I often charge various devices.
  • Code doesn't limit the number of outlets per circuit, so a better question might be, number of items per circuit rather than outlet.

    • by vlm (69642)

      Code doesn't limit the number of outlets per circuit, so a better question might be, number of items per circuit rather than outlet.

      For those not in the business, arguing about NEC 220.14 (I) is pretty much the electricians equivalent of vi vs emacs, it gets very loud, often personal, and no one really cares, aside from acknowledging that its an area "subject to differing interpretation".

      If you believe 220.14 (I) applies then you're limited to a crazy minimum 180 watts per receptacle so that gives a crazy high, yet hard limit to the number of outlets per 15 amp ckt.

      If you believe 220.14 (I) does not apply then the above post is true, I

    • Actually it does. You're supposed to assume 180VA/outlet and the total shouldn't add up to exceed the circuit capacity. Unless you're in a bathroom or kitchen, then the rules change and are more restrictive. You're also not supposed to string together additional outlets if you know there's going to be a large load at that location -- say for example a rack of servers, which should get it's own circuit(s).
  • Hair dryer plus microwave on the same circuit pops the breaker every time. Number per outlet is entirely less important than total wattage per circuit.

    Pile of wall warts, flourescent bulbs in desk lamps, radio, etc all on one circuit draws far less than any hair dryer, microwave, and most PC's.

  • As some already said, the most problematic thing is total power. Ok, when you start plugging too many things you'd better start looking for badly connected adaptors and short circuits too.

    I've already plugged on the same outlet 4 computers (that means 4 monitors, and 4 speaker sets), with normal periferals, AKA, a printer, scanner, a telefone, some sporadic chargers, modem, switch, external drivers, PDA, etc. A quick calculation showed that the risk of the outlet burning was small, and none of the wiring ha

  • The problem isn't the load.
    Wall-warts and computers don't draw that much.
    The problem is outlet density.

    Each wall-wart takes one outlet, and typically blocks one or two others.
    That eats up plug strips fast.

    I like to string grounded taps [yourstorewizards.com] together.
    If you shop around, you can find them for maybe $3/each.
    Each one accommodates 2 wall-warts, for a final cost of $1.50/wall-wart.

  • Wattage matters as others are saying. From what I've heard the UK can use up to 3000 watts safely. The US is about half of that AFAIK. It's a crying shame that we in the UK can have convectors which heat up the room more quickly, electric kettles which boil in half the time, microwaves which cook in half the time and vacuum cleaners twice as powerful. If the US switches to 240v, then not only do they gain, but we get closer to standardization, and an electrics market can gather pace across the world more
  • I`ve run 8 modems, two outdoor WAPs, and an x86 firewall from a single power brick, with battery backup. Adding a server and ATA to that list shortly. If only my switches took DC input; I may have to crack them open to find out...
  • I recently worked in a brand new scientific laboratory. There were huge lab rooms, big enough to house 10 tables with twice as many people on them. There was ONE plug in the wall. Sometimes architects ought to be shot.
  • by ben_kelley (234423) on Tuesday February 08, 2011 @06:53PM (#35144170)

    I was setting up sound and lighting for a small outdoor event. We had power from 3 outlets, with a maximum capacity of about 2,500W per outlet. Plenty of capacity for a mixer, power amp, powered sub-woofer, and a couple of spots.

    Things were going fine until we lost power to the mixer and a couple of the spotlights. After tracing back cables I discovered that the overload protection on one of the power strips had tripped (without knowing why). No problem - press the button and we're back in business.

    The second time it happened it must have melted the overload protection, because the lights went off and on again a couple of times, and then the smoke started.

    "Did anyone just plug something in to this?"

    "No. Well only these lights.

    "Can you take a look on the back of those and see how many watts they are?"

    "This one says 2x500W. I presume the other ones over there are the same."

  • by gordguide (307383) on Tuesday February 08, 2011 @08:41PM (#35145220)

    As others have properly pointed out, the number of items is irrelevant, at least if safety was the intent of the question.

    The total maximum current draw is more significant, as is the kind of load put upon the circuit. A refrigerator or air conditioner is a different load than a heater or hair dryer, which is a different load than a transformer-powered device, which is again different from a switching power supply device. They each have their little electrical "quirks" and draw power somewhat differently, and that does matter with regard to the load you're asking it to provide.

    A lot of people think that the house wiring can supply a certain, finite amount of current, limited by the safe rating of the outlet. For example, they might assume a 15 amp 120V circuit can supply the 1800 watts the math suggests (A x V = W). Even if they're aware that this 1800W is only available at the breaker box, not after the losses in getting that power to your outlet, and even if they're aware that the utility may not be always supplying a steady 120V (if, for example, the utility drops voltage to 110V for a few hours a day, the maximum falls from 1800W to 1650 for that time period) they still see the power outlet as supplying a finite amount of energy.

    That's not how it works (and professionals, please excuse the simplification of what is to follow). The outlet will happily and dutifully try to supply whatever you ask it to ... if you plug in 2200W of "stuff" into the outlet, your electrical system will try it's very best to give you the 2200 watts. It will probably even succeed for a while (maybe not 2200 watts, but some value greater than 15A and 120V), given a well implemented setup and solid work by the electrical contractor who built your home. In fact, the utility and your home wiring are often robust enough that you may get away with that overload enough times that you may believe the number of things you've plugged in is a safe load. After all, you plugged in that "extra" thingy and it worked, right?

    It's protected by a breaker at the utility service entrance, right? That breaker is rated at [some value] so as soon as you ask for more electricity, it will trip and tell you it's too much, right?

    Wrong. The breaker has no idea how much electricity you're asking for. It doesn't trip at 15 Amps and 120V. It senses heat, an indirect measurement of voltage and current, not a metered, precise amount. Breakers can fail, each time they trip they become somewhat less reliable, and they only are built to "guess" that a certain amount of heat is equal to a certain amount of electrical load. They're not speedometers.

    So, it's an overload. There will be heat and sparks and who knows what happening inside the walls. Sooner or later, there will be a fire.

    It's not like the garden hose where given your water pressure and size of lines, only so much water is going to come out. Ask your electrical system for more, and it will give you more. Until the fire, that is.

    A certain safety margin is required, and that depends on the age and condition of your wiring, the quality of your utility's power delivery, and a few other factors. The best advice is to use a safe load limit as your guide; from standard North American power that would be probably around 1350 watts at the outlet. Go above, and trouble might be the next thing that happens.

    • It's protected by a breaker at the utility service entrance, right? That breaker is rated at [some value] so as soon as you ask for more electricity, it will trip and tell you it's too much, right? Wrong. The breaker has no idea how much electricity you're asking for. It doesn't trip at 15 Amps and 120V. It senses heat, an indirect measurement of voltage and current, not a metered, precise amount. Breakers can fail, each time they trip they become somewhat less reliable, and they only are built to "guess" that a certain amount of heat is equal to a certain amount of electrical load. They're not speedometers.

      That's not quite right. A resettable breaker (i.e. not a fuse that has to be replaced) measures two parameters. The first is indeed heat. That's to trip before the wire reaches dangerous temperatures in a moderate overload for a long time scenario. The characteristics of the breaker will indeed specify how much overload it will tolerate for how long, otherwise starting motors etc. would be a bear. That's as it should, in a properly designed and installed circuit the breaker will trip long before you have an

I am not now, nor have I ever been, a member of the demigodic party. -- Dennis Ritchie

 



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