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Hardware

Getting Power to a Rack Enclosure? 92

JazzyJ asks: "I need some ideas on some fire/electrical code compliant ways to get power into some bare bones rack mount enclosures I have. The racks are essentially in the center of a room with 3 ft around all sides. There's a 4 outlet box on each wall. Other than getting building maintenance to drop me a circuit along the floor or out of the ceiling, what options for getting power into these monsters do I have? Extension cords are right out, that is against fire/electrical code. Help!?"
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Getting Power to a Rack Enclosure?

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  • by Godeke ( 32895 ) * on Monday December 15, 2003 @06:43PM (#7729122)
    Since you didn't specify where you are, and fire codes depend on local, I will assume you live in Greater Elbonia.

    Greater Elbonia has virtually no safety laws, being mostly mud flats with little natural resources and almost no government. Therefor, if extension cords are out (which surprises me, but perhaps they short out in the mud) and you can't get drops properly placed by building maintenance (and I can imagine how hard that is in Greater Elbonia), I would suggest beaming microwaves from the wall to the rack.

    This has several advantages: *
    1. Lunch now becomes a simple matter of placing your food between the microwave emitter and the rack. Don't place too much food there at once, or your might cause a power drop.
    2. Any annoying building inspectors or managers should be directed through the microwave beam, thus saving you much more time in the future not dealing with annoying building codes or management requests.
    3. Hey, no cords!


    * Advantages may be outweighed by frying every circuit in your computers.
    • true story (Score:4, Interesting)

      by morcheeba ( 260908 ) on Monday December 15, 2003 @07:17PM (#7729487) Journal
      very funny!

      True story: a customer had one of our systems in a rack, and it worked great when all closed up. But as soon as they opened the cover to see the pretty lights that blinked while we recorded the data generated by their radar system, the system stopped working. We had debugged it in the lab with the covers off (albiet with simulated data), so it should work best in this configuration.

      Problem: humongus radar sitting on the roof of the building was glitching our circuit... that was the radar we were recording data off of, and the whole purpose of our system. Closing the front cover shielded us. We had concentrated on recording the binary data that their A/D's were giving us, and had forgotten the implications of the source of this data.
  • Telepathy! (Score:4, Funny)

    by T-Ranger ( 10520 ) <jeffw@NoSPAm.chebucto.ns.ca> on Monday December 15, 2003 @06:43PM (#7729128) Homepage
    You have something that needs power that isnt close to an outlet. You dont want to use extension cords. You dont want to get new outlets installed. So far as I understand how electricity, only the subject is left.
    • well.. he could use light to transfer the energy, or microwaves. i was going to answer magic though("powerutus rackatus").

      seriously this just about the most stupidest ask slashdot(not the most, there have been ask slashdots that have been way much more stupid). unless he has lifted floors i'd go for the ceiling solution.

    • by Tom7 ( 102298 )
      You forgot moving the object closer to the power outlet!
      • He said 'rack'. Racks are bolted to the floor, otherwise they fall over if you put anything in them over about 300 grams. Unless he dosent know what he is talking about and meant 'cabnit'. Which, given the question, is quite possible.
        • Actually... my school's rack is bolted to the wall(!) and is somehow holding together. Yep, it's got all of their networking equipment except for a hub in each classroom... Scary, isn't it?
        • Well, if they bolted them to the middle of the floor and then realized that there's nowhere to plug in the equipment, they might consider unbolting and rebolting somewhere else.
    • there is a easier method than telepathy, why not use water? Yes, I know that pure water doesn't conduct electricity, but with some salt, it does! So all what you need to do is to pour water through out the room, add salt (experiment until you get good conduction), use 2 cords to connect your electrical devices to outlets through water, and you're done!
      • Good idea! However, I have a better one:

        Just run a big fat hose from the nearest water tap and pipe it into a small hydroelectric turbine near the computer rack.

        Advantages:

        Shielded from spikes on the grid

        Use the water to cool the servers

        UPS functionality - as long as you have water, you have power

        The whine from the turbine will drown out the whine from your manager

        No cords!

  • Consult an expert (Score:5, Informative)

    by Anonymous Coward on Monday December 15, 2003 @06:45PM (#7729150)
    - Pick up local yellow pages.
    - Look up number for an electrician.
    - Call the number, and ask whoever answers the same question.

  • by Anonymous Coward
    I've come across the same problem, and I came up with the following solution:

    equipment required:

    4 Microwave ovens (800W or greater)
    4 metal trash can lids
    40' copper tubing

    Oh crap, I'm late for my brain tumor treatments, but as soon as I get back I'll post the rest of the instructions...
  • Would something like this [blackbox.com] (a rack-mount power strip with 15-foot cord) be what you're looking for?

    (Pay no attention to prices, Blackbox is just the first pro-stuff vendor with an online catalog that came to mind; I'm sure you can find something elsewhere for [much] cheaper.)
    • Re:Just a guess... (Score:3, Informative)

      by aaarrrgggh ( 9205 )
      Technically, this doesn't meet code in most jurisdictions. You can end up needing to put in an EPO system (big red button that makes the room quiet) if you go that route.
  • I'm wanting to better conceal the tangle of cords around my many computers, as well as keep them out of the teeth of household pets. (I haven't yet looked at fire/safety codes for Nebraska.)

    I've been considering installing pullable tiled office flooring in my basement that brings the floor up three inches and stringing my cables underneath it.

    Or consider that you might not need four-side access to the rack. Front and back seem to be enough for me, so I hid my CDC Network Processor Unit cabinet behind th
    • Uh, wouldn't it be a better idea to keep the pets out of the computer rooms? Last time I checked, having your dog pee on your motherboard wasn't really good for it. I've also know birds to chew through power cords, but they usually only do it once...
      • Actually my cat liked to continually chew through the power cord for my iBook. She would continually get shocked by it and I've even seen sparks fly but yet she continued to do it anyways. Luckily when I got a replacement cord it was a newer version and my cat didn't like the plastic it was made of,
      • In this case it is a kitten.

        The computer room is also the media room. Computers on one wall, 32" HDTV and video equipment on opposite wall, and a Firewire connection between them (and 3 powered Firewire hubs to go the distance between them).

        I'm in that room most of the time, and I don't think it wise to leave a new kitten on its own all the time. He needs attention if only so he can learn proper behavior. He isn't in the computer/media room without observation.

        The cables are also a trip hazard for mys
        • Never had a problem with cats chewing wires. Did live with a cat who used to jump up on the keyboard every time she saw me in front of the computer in a ploy for attention -- which is probably what your kitten will do when it gets older.

      • My pet problem has been the scent-markings of 3 cats who don't always get along. They get everything. The file cabinet. The bookshelves. The desk. The computer cases. They even got up on the desk and got the ZIP drive and scanner. It's awful. Keeping the door shut helps, but not when you don't realize that one has hidden himself in the back of the closet, and you've now locked him in instead of out.

        The solution, for the tower cases at least, was to set them in open-topped plastic totes. The air could

    • out of the teeth of household pets

      Can I tell a dumb story? Great! Back in the NT4 and dialup days I had this little chihuahua that was teething, and we all know that when a dog is teething it chews whatever the crap it wants and nothing you give it to chew. So I would try to keep him out of the computer room because he would sit under the computer and chew wires, and pretty soon the KVM would stop working, the left speaker would go silent, but luckily he never got anything high voltage ...

      Now anyone

  • Subject says it all. TrippLite UPSes come with 15-foot cord. Similar with other brands, I expect. Of course, you're still screwed, because a single outlet will only give you 15 amps (or 20, if you got good power). Which is not enough for a serious rack.
    • Of course, you're still screwed, because a single outlet will only give you 15 amps (or 20, if you got good power). Which is not enough for a serious rack.

      Oh, do I rue the day my wife brought home a 10amp vacuum cleaner... though she is still laughing at me for having to adding a circuit because I got a "deal" on an HP laserjet.

      No question, time to talk with an electrician.
    • They could always put a bunch of UPS's in the rack, then a couple times a day run extension cords and plug them in, then when people are coming by, unplug them :)
    • Speaking of disguises...

      Re-splice the cord to your power supplies or UPSes. Go to Home Depot and get 30-amp rated 3 wire power cabling and some plugs. Should work well. Run it through floor conduit (those platic troughs) so people don't rip the cords out.
  • by jeffy124 ( 453342 ) on Monday December 15, 2003 @06:56PM (#7729266) Homepage Journal
    depending on the local code, the extension cords might only be restricted from running across the floor because that could be a tripping hazard. It might (again, might) be ok to string the cord up the wall, along the ceiling, and dropping down to the rack. Another option may be getting one of those long (several feet long) rubber covers that go over the cord and provide a small hump to walk over for people in the room. (like these [cleansweepsupply.com] - first hit on google)
    • generally, fire codes don't like extensions cords to be permanently installed, even if you can't trip over them. (I'd like a reference, but I'm feeling lazy, so I might be wrong. That's just experience from when we wired up our lab and resorted to adding permanent taps)
      • by Spamalamadingdong ( 323207 ) on Monday December 15, 2003 @08:04PM (#7729909) Homepage Journal
        That's one option. Another (and possibly better) is just to put wires in conduit (run it 7 feet off the floor to avoid trip and head-banging hazards). You'll have to check your building codes to see if you can put a fat 3-wire cable inside conduit for the run through the air and down the wall to an outlet, or if you are required to run separate wires (better heat dissipation) and wire things directly into a junction box. That latter will certainly require intervention from building maintenance.
  • If you can't move the outlets closer to the racks, why not move the racks closer to the wall?

    Or, if the racks are too heavy to move, why not put another rack halfway between wall and current rack and you only have a couple of inches to bridge instead of 3 feet.
  • by Dr. Bent ( 533421 ) <<ben> <at> <int.com>> on Monday December 15, 2003 @07:01PM (#7729323) Homepage
    Dear Slashdot Readers,

    Will you please do my job for me, as I am too fat/lazy to pick up the phone and call an electrician. Besides, my special dialing wand hasn't arrived yet and, technically, I shouldn't be using the phone at all for medical reasons. Tell you what! To make it extra fun, I won't tell you where I am or any local laws that might apply to my situation. Let the endless speculation begin!

    Oh, and please hurry! I'm trying to leave early today and my boss wants an answer first thing in the morning.
    • by R2.0 ( 532027 ) on Monday December 15, 2003 @08:35PM (#7730188)
      You forgot "And I want to do it as cheaply as possible, preferably only spending the breath it takes to say 'Waaahhhhh'".

      Apparently people are building "server rooms" with
      1. No cooling
      2. No power
      3. No effing sense
      and are then asking to be rescued. It's like asking Lucy VanPelt for therapy.

      The Doctor is OUT.
  • When I was about 5 years old, I thought I tried making an extension cord with an unbent coathanger. The way it worked was I ran the wire through those little holes in the prongs of my clock radio, then the other end through the prongs of a fan. When I plugged it in.. POOF.

    The results were pretty, but I wouldn't recommmend getting power to your rack this way. I had a hard enough time explaining to my dad the scorch that went up the wall, let alone the clock radio never working right. Though I think I kn
  • by stevef ( 5539 ) on Monday December 15, 2003 @07:08PM (#7729393)
    ... aside from doing it the safe/correct way, how can I save a few bucks and reduce the risk of buring down my office?
  • by ghostlibrary ( 450718 ) on Monday December 15, 2003 @07:16PM (#7729466) Homepage Journal
    Well, if it's anything like the university I went to, it's easy!

    1) Put in a request to the building&grounds people that you need a new junction box placed within easy access of the racks.

    2) They promise you a quick response.

    3) After six weeks, realize you need power _now_ and run a few power strips through the floor panels.

    4) Union rep appears 1 hour later, removes strips , fines your department for using non-union labor.

    5) Wait 2 more months, still no response from union electrician. Run an extension cord from your office, across the hall, into the room, thus not violating Union reqs (no floor panels touched!)

    6) Fire marshall appears, fines department for fire hazard.

    7) Dean of department calls you in, explains they are firing you due to the trouble you've caused in fines and Union difficulties. Voila! Problem solved, you no longer need to worry about power to the racks!

    (And oddly enough, I support unions in general!)
  • Wires (Score:4, Funny)

    by Uma Thurman ( 623807 ) on Monday December 15, 2003 @07:16PM (#7729470) Homepage Journal
    I'd suggest using copper wires to get the power to the rack. I was in Home Depot yesterday, and it seemed that they had some very reasonable prices for short lengths of wires. It shouldn't be too much trouble to get approval for the purchase. Glad to help.
  • drop (Score:4, Informative)

    by BigBir3d ( 454486 ) on Monday December 15, 2003 @07:44PM (#7729766) Journal
    Easy to get a chessy metal pole for your ceiling drop. We use several in our office (open floor plan, no desks near a wall) that have both power and ethernet jacks. Takes all of about 20 minutes to install, plus time to run cabling to the desired location. Ours are even UL listed.

    HUBBELL
    Multi-oulet assembly
    HBLPP10A
    Issue No: 3084

    Found here [grainger.com].
    • Re:drop (Score:3, Insightful)

      by jjshoe ( 410772 )
      Incredibly easy/cheap/quick/efficent which is why you see them all over offices everywhere.
  • by borgboy ( 218060 ) on Monday December 15, 2003 @07:47PM (#7729793)
    You didn't really say why asking building maintenance was an untenable option. This is a relevant point, as, if they're competent, they'd do what a typical electrician would do anyway. Why not drop from the ceiling/floor?
  • General comments (Score:4, Informative)

    by aaarrrgggh ( 9205 ) on Monday December 15, 2003 @08:05PM (#7729911)
    First, extension cords are limited to 6' by the National Electrical Code and UL. If the cord is longer than 6', it is supposed to have larger wire than what is normally provided (#14 for 15A vs. #16/18 typical extension cord). Outlet strips are generally considered "temporary" wiring, and is a code violation. YMMV

    Running cables along the floor is a bad idea both because of the tripping hazard, and the potential to short out the wires.

    Get an electrician out there and have him move the circuits to the racks. I would recommend having a about 3' of slack (LFMC conduit), and attach the outlet box to the rack via "temporary" means.

    (If you are in CA, you don't want to make a permanant connection to the racks, as supplemental seismic bracing may be required.)
    • First, extension cords are limited to 6' by the National Electrical Code and UL. If the cord is longer than 6', it is supposed to have larger wire than what is normally provided (#14 for 15A vs. #16/18 typical extension cord).

      I'd be really interested in an NEC cite for that, since I don't recall reading that in the book, handbook or explanatory documents.

      And the UL bit is interesting also. Care to explain how Home Depot can sell a 50ft, 16ga, UL listed cord? (eg Model 000-HD809-543, Store SKU# 809543, I
      • For the 6' cord limitation, the best I can remember is the branch circuit requirement in Article 210-52 for dwellings; I can't find the Article 422 reference for cord length for "general appliances." The length is sometimes referred to as 6', sometimes 2m.

        Per NEC Article 305-3 (1996), Temporary use is considered during periods of construction, 90 days, or during emergencies and tests.

        Article 400 provides information on flexible cords and connections, including permissable uses. It specifically states t
  • Get an appropriate INVERTER [xantrex.com] sized to your needs

    Get as many Submarine StandBy Batteries [used-line.com] as needed to run this for the expected period of time. (months, years...)

    Now you have the Rack powered with no external wiring!

  • 1) Resign from your job. You're obviously not qualified if you have to "Ask Slashdot" for something this moronic. 2) Realize your question answered itself. Just think, there's not really any other logical solution aside from getting floor or ceiling outlets installed. 2) Enroll in kindergarden. Repeat education, you obviously didn't learn much the first time(s?) around. 3) ????? 4) Try to get your job back.
  • I wanna fly (Score:3, Funny)

    by nocomment ( 239368 ) on Monday December 15, 2003 @08:21PM (#7730060) Homepage Journal
    But without using wings or tools or jumping from anything. Basically I want to start at the bottom of a canyon, and rise up to the top.
    How can this best be accomplished without using wires/cords, or any sort of attachemnt/tractor beam?
  • Get local (Score:3, Insightful)

    by BSDevil ( 301159 ) on Monday December 15, 2003 @08:58PM (#7730372) Journal
    The fire code in MY jursitiction says nothing about extension cords. It also says nothing about alarm systems, halon, or the purchasing power of ferrets. Although you don't say where you are, I guarentee you that my fire code dosne't apply there - and as such, my advice will have zero value.

    You're obviously a competent guy - you thought to see weather what you wanted to do was legal, as opposed to many who would just have done it. So why not take the extra step, and hire someone who's job it is to know the particularities of your local regulations? There may be a wealth of experience here, but that dosen't make up for being a licensed electrician located nearby who can come and inspect the place and tell you what you need.

    Normally, I support doing it yourself. But if you're going as far as thinking of fire codes, you may as well get the right answer (and I suspect your insurance premiums may thank you too).

  • I would say 1357 Gerbils/CPU should do it. Don't forget to grease the wheels, or you'll go mad the next time you have to install an OS.
  • Simple!
    Step that sucker up to 500 Kv and power it directly FROM the wall - No steenking cords required!
    Get a big vacuum pump to remove the air from the room and you're happenin!
    Of course fans don't work so well when there is no air (although they spin REALLY fast), you might have to investigate other methods of cooling.

    No need to send money, I'm just Glad I could 'Help'!

  • professional electrician. It's well worth the money you'll pay. Or save, considering if you do it yourself you'll probably start an electrical fire
  • Wormhole (Score:5, Funny)

    by paul248 ( 536459 ) on Monday December 15, 2003 @09:46PM (#7730723) Homepage
    Well, Since you've ruled out running cables through the three known spatial dimensions, I suggest you try using a wormhole. Simply generate a wormhole (in the usual way), and, using a pair of exotic matter gloves, place one end of the wormhole inside the rack. Then place the other end near an outlet; this outlet can be near the wall, or some outer region of the universe... basically, wherever you can get the cheapest electricity. Next, simply plug in the cord, and feed it into the hole. I would advise that you perform this step from outside the cosmos, especially if the wormhole hasn't been thoroughly tested to comply with local building codes. If the universe as we know it hasn't been completely obliterated at this point, then you're done!

    Note: You may also want to run your ethernet cables through there as well, to function as a very convenient, low-cost hyper-dimensional gigabit wireless network.
  • You'll probably need an electrician.

    But, to get power/data cables into free standing racks, why not just user ladder panel? It's relatively cheap and most drywall type laborers can install it. I prefer chatsworth ladder panel myself, but just about any will do. Some people even like to do double decker to keep power on one level and data on another. As for the actual cable runs, you can probably get an electrician to come in and install twistlock style wall outlets for you so the cables aren't accide
  • Why hasn't anyone suggested wireless power transfer through microwave beams? I mean, come on, this is slashdot, we're always supposed to offer a wireless solution.
  • Just get a pair of microwave tansducers and rock on! As a fringe benefit you'll have quick & easy fried eggs, right in your office, and coocked on an uber-geek equipment! And you can fry your PHB's cell phone if you're cunning enough... just read some BOFH hints on The Reg [wwwteregister.co.uk]!
    PS. /. disses my leet utf (whatever) character codes from my OSX mac... where is my (mu) or u (u with the .. )? oh come on!
  • First: Thank you all for the responses.

    Second: The reason why I asked slashdot was to really get a feel for some of the less obvious solutions that perhaps myself or our building maintenance personnel might come up with.

    The unfortunate reality is, even though it is not the ideal, sometimes you do need a less expensive solution. I work for a municipal government. Politics and managerial whims dictate a great deal as to what has priority. The best plan/budget don't mean squat if the City Council or Cit
  • Unless you live in a strange area (where laws let you do things you can safely do...) you legally have to call an electrition to do this. Your facilities guys cannot do this, so they won't help.

    • By law in any commercial (and most definitely Government) building you MUST have a LICENSED electrician perform this work. The local maintenance guys cant even do it.
      The electrical code for residential wiring is large, for commercial buildings it's very large, and for industrial it's scary!. You need an electrician.
      -Steve
  • At work, we have a 6-foot plug strip attached to left and right rear of each cabinet. Each of the plug strips is connected to a separate, diverse, UPS'd, circuit (usually 20 amp). A quick search for "plug strip" on eBay reveals a 16-way Tripp Lite plug strip ($55). Plug one device into each socket on the strip. If you run out of sockets, get another plug strip, 20 amp circuit, etc. Rinse. Repeat.
  • by PapaZit ( 33585 ) on Monday December 15, 2003 @11:46PM (#7731567)
    Oh, come on, people. We shouldn't give up just because we've been given an impossible situation without enough information. This is Slashdot! B'sides, these specs are more detailed than anything you'll ever see in the real world. Some ideas:

    -Plug a Van de Graaf generator into the outlet. Put wires on top of the rack (e.g. a lightning rod). Attach to a capacitor and a DC-AC converter, and you're golden.

    -Set up a bunch of rechargeable batteries and an army of Lego Mindstorms robots to shuttle the batteries back and forth from the outlet to the rack.

    -Put in really bright overhead lights and solar panels on top of each rack.

    -If you have a good AC system, thermal couplings between the AC and the machines might generate enough power. The laws of thermodynamics were made to be broken!

    -Hamsters, water bottles full of Jolt cola, and hamster wheels hooked to generators.

    -Finally, Steampunk is not just a frings Sci-Fi/RPG genre. A few cans of Sterno and a boiler can provide you with enough steam to run whatever computational engines you might have.
  • Anybody that's anybody knows that tesla coils [mtu.edu] are the BEST form of wireless electricity! Of course a giant one supposedly destroyed part of Siberia (or something), it should work fine.

    Klowner
  • I am dismayed by the lack of usable suggestions. Here is some more practical.

    1. Purchase a very large fan [ebay.com]
    2. Get a 12v to 120v inverter
    3. Purchase one of these turbines [lehmans.com]
    4. Install the turbine on the rack and wire up the inverter to your gear
    5. Plug in the fan and enjoy your creativity (Great cooling performance is a bonus)

    Think outside the box? I believe that the is no box!

    SD
  • Remember that there is some resistance in this, but if you can get some contacts in close enough proximity to the source of power and externalize that, you can have these really cool arcs coming from the source of power without actually using extension cords, and make it look like a mad scientist's lab. Be sure however you use a 440 plug for the purpose, and that you transform the power back down to the local requirements (110 volts here in the US, 220 in many places abroad) so that you don't kill your equ
    • 440 volts won't provide a long enough arc. Use a big Tesla Coil instead. Then store the power in a big high voltage capacitor, and use inverters and transformers. I bet the codes don't talk about this. ;)
  • So, fire codes prevent you from running cords across the room. Here's plan A...

    Place a large electrical motor near the power outlet. Place a generator in the rack. Connect the two with either a V-belt or a shaft.

    So that OSHA (or your state industrial safety office) doesn't have a fit, be sure to install appropriate guards and lots of labels with DANGER! in large, block letters.

    Plan B: Similar in concept, except that instead of an electric motor, you run a garden hose to a turbine directly connected to th
  • C'mon, I'd expect that this would have been the first solution, considering the forum!

    It this becoming Slackdot?
  • Hire an electrician. You know, these guys are specializing in setting up stuff like electrical chords. There is a good chance they could help you setting up your electrical chords...
  • Move everything closer to an outlet. You'll have to choose which one though and I can't help you there. I will suggest the one on the left though.
  • For her birthday, I purchased a rack enclosure for my girlfriend, and it came with built in underwires. Haven't tried it, but I'm sure you could use those.
  • A small nuclear device should do. Assuming you can't get Pitr's [userfriendly.org], try contacting Toshiba [toshiba.com] about the one discussed in this story [adn.com]
  • There is one plus to all the lame "Ask Slashdot" questions where the right answer is - go call a pro you lazy bum... There are tons of good funny comments. :) If someone can't figure out how to use a phonebook, phone, or google - how the hell are they reaching slashdot anyway? Is some software installing a "visit slashdot" shortcut like they do with AOL links? Hmmm
  • The important part is the UL listing for
    the PDU, preferably mounted in your rack.

    That makes it a legal install in all the
    US electrical codes that I have heard of,
    and a simple "buy one, install it" solution.

    rb
  • Use Ladder rack from the wall to the cabinet, then run power over the ladder.

    The ladder should be 7' or higher from the floor.

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