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How a Wiring Rack Should Look
Julie Jacobson writes, "It's so much fun to deride some of the worst home wiring jobs in existence. But once in awhile, we should salute some of the cleanest, most perfectly labeled cabling jobs in U.S. homes. At the recent CEDIA Expo, the association for home-technology integrators handed out awards for the Best Dressed Systems, each featuring miles of cable, hundreds of connectors, tons of steel, and a clean aesthetic that could make the most finicky designer swoon. Show them to your own installer for inspiration."
Found an old picture of one of the messiest racks I have ever seen. Personally I think a messy NOC should be a punishable offense. I can't tell you how many times some stupid blip in the system is caused by a dangling wire with so much other wiring hanging on it that it gets pulled from the panel. Nothing like a 4am pager going off, coming into work and finding the root cause of the problem is the idiots that wired the rack. Kudos to those who do it right.
Funnypics
http://www.talkaboutcedia.com.nyud.net:8090/articl e/10397/ and here's another mirror
but can a linksys wireless router actually work inside of a steel cabinet?
Do you have ESP?
... there is such a thing as carrying it too far. I'm reminded of the tale of the junior sysadmin who proudly showed the senior sysadmin the cabinet he'd just wired up. Very neat, very pretty.
...)
The senior sysadmin looked at it thoughtfully, then flipped a single switch. Every server in the cabinet went down. Yup: every server had its entire power source coming from a single rail, instead of having the two redundant inputs coming from different rails.
Where I work, every cable to every server in the machine room is labelled at both ends. The patch panels are also labelled with the address of the other end of the cable. Makes troubleshooting network problems a lot simpler (and that's important when you're talking over 200 servers on the floor
A super-neat wiring rack is great, if you don't need to get to the wires often. If you need to rearrange wiring often (for whatever reason), there is no point in making it look great (though a certain level of neatness is required for optimum efficiency).
When they wired their mainframe, they spent about $2000 for a bunch of bix panels.
When it was my turn to do the same job, I took $5.00 and went to the hardware store, I picked up a 1ft by 4fr plywood scrap and bought a box of finishing nails and brought that in the office (the canadian head-office of a fortune 500 company, btw) and started hammering away neat rows of nails to which I soldered wires from a 100 pair cable we ran between two floors.
On hearing the hammering, the boss of the other department (who happenned to pass by by chance) came to have a peek, and he sees me hammering and soldering and asks me "what are you doing???"
- I'm doing a patchboard for the serial lines.
- Why don't you use a BIX board like we did in the plant?
- Because yours cost $2000 and mine only $5.00.
He left without saying a word.
Here is a picture of a site in Dallas, TX. This picture belongs to a HUGE telecom company. A baby bell if you will. ;) How they maintain this I will never know.
http://www.waystupid.com/item-378.htm
What is more amazing is that after several attempts by staffers, the management refuses to let people clean this up. And they show this to prospective customers on a daily basis!!!
Mike @ The Geek Pub. Let's Make Stuff!
In our computer room I just provide plenty of wire management, a wide assortment of cable lengths, and a picture of the wedgie I gave the last admin who kludged something 'for testing' and left it that way for months.
"Also, the editor put an incorrect link in."
Guess he got his wires crossed ...
Comment removed based on user account deletion
I'd like to be a judge on that panel. I'd love to give out awards for the best rack.
What? Wiring? What are you talking about? Oh...
"All great wisdom is contained in .signature files"
While viewing the article, my wife overheard me saying, "Ooh, nice rack on that one.
Warning: The intelligence of this post may be larger than it appears.
You want to know what I didn't see in a single one of those "neat & tidy" wiring photos? I didn't see a single service loop. Sure, anybody can wire-tie the heck out of something and make it look nice and neat on project completion day. Hell, I used to produce racks of similar tidiness when I was 19, working for a regional communications installer doing hospital and school networks. But it takes a real artisan to make something look that neat AND design it to stand up to five years of corporate changes and rearrangements. Just wait until one of your wires has to move from the top of the rack (near the entry point) to the bottom of the rack.
I think it was a previous comment that wrote: "Neat != Usable" That's so true. (Or Neat !== Usable for you PHP-tards)
"I threw up my hands in disgust and wondered if it had been such a good idea to have eaten my hands in the first place."
I didn't Read either of TFA, because they seem to be slashdotted at the moment.
However, after years and years of living, I can tell you that "if a job is worth doing, it is worth doing well" is just not true. Sometimes doing a job "good enough" is more than enough. It might get torn down next week. If you wash the windows "OK", that is probably good enough, they'll be dirty again soon enough.
It all depends on what you are doing. Building a house? Do it well. Wiring a computer cabinet? Pfft - make it good enought for a few years. It will change. RS-232, thin-wire, thick-wire, 10BaseT, Cat 3, Cat 5, Cat 5e... Fibre... whatever.
If you can do a 90% job for half the cost you will have enough left over to do another 90% job of something twice as good 4 years from now.
Maybe. YMMV.
This issue is a bit more complicated than you think.
I honestly don't think that it was much of a problem for RS232 communication (i.e. high-voltage, relatively low frequency).
The Raven
To a limited extent, I agree.
Neatness is one thing, but those examples just look like an advertising photo for nylon wire ties. I mean, they look nice now, but what happens when you need to move one of those connections around, say from one port to another?
You'd have to cut 50 different ties, and all the wires are cut to such precise lengths, you'd probably end up having to splice some sort of nasty extender in there (adding a significant insertion loss due to the connectors or splice). It would be a total mess. Having everything wired in drum-tight may look nice, but it's a bitch later on. Something that has more "drip loops" before all the wires get bundled up into single harnesses may not look quite as polished initially, but it's far easier to work on down the road.
I've worked on audio systems like this, and it always strikes me as something that you'd do if you were a contractor working on a one-shot job, something where you want to impress the client and justify your fee, with no real thought to maintenance later.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
...Can one create a duplicate within the same submission.
Ha Ha, impedance in a low bandwidth, 40 year old communications protocol going a few metres?
Sounds like the electrical engineering equivalent to a computer scientist berating Aunt Tillie for using a spreadsheet to calculate her finances because of "costly floating point operations".
When Argumentum ad Hominem falls short, try Argumentum ad Matrem
... sometimes it has a tendency to get to your head. You didn't get your EE degree for hammering some nails to string RS-232C, any more than a doctor gets their degree to treat a common cold in a healthy 8-year old. In the same fashion, I didn't get my CS degree to write Swing UIs. Did our educations tangentially cover these things? Yep, they did, but they're a) not our core competencies and b) can be done by someone who is literate and capable of following a simple single sheet of instructions.
Why are our degrees important? Well, one thing they let us do is properly identify edge cases. A self taught programmer implementing a Swing UI with a sorted combobox might decide to use a bubblesort on it, which would work fine through testing right until it got to a customer who put a couple hundred items in it, when the application would just start to unexpectedly hang. The doctor hopefully catches that 1 kid out of 10,000 who doesn't actually have the cold and needs treatment within the next 48 hours to save his life. And you, as an electrical engineer, identify when impedence would be an issue.
Ah, but here's the rub: edge cases are edge cases for a reason, and purported experts who cry wolf regarding the edge cases get ignored by a public which sees solutions which work perfectly for 2.5% of the price. And, as several folks have pointed out, you're crying wolf here. The reason the solution appears to work isn't because the grandparent was ignorant of impedence, its because its just physically impossible for that to be a problem for that device.
Or, as I learned in Engineering school (in tech writing, of all places): "You're going to graduate with a degree from one of the best schools in the country, and you'll be working your first job with tech-school grads who have 15 years of experience, and in your first two weeks one of them is going to say something you learned in school is wrong. You might disagree, perhaps vehemently. But before you voice your disagreement, figure out exactly why he thinks his way will work, because odds are it will. Remember: he's worked there for 15 years and hasn't blown it yet, or he wouldn't still be there."
Help poke pirates in the eyepatch, arr.
This article sponsored by; ZipCo International.
Manufacturers of the worlds most reliable and most costly zip-ties!
Organize your wiring cabinet today! You can never use enough zip-ties!
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
Your average network TV station has wiring that puts any telecomm to shame. I've seen patchbays just in control rooms that have far more going on than anything in the photos on the CEDIA website. That stuff *has* to be organized. Just the labelling systems are amazing, let alone the craftsmanship involved in wiring them.
-fb Everything not expressly forbidden is now mandatory.
You're totally right. That's something I've learned at my new job. I was always trying to do things perfectly, and I realized that it took too long to do them as well as I wanted, and even then they wouldn't be *perfect*. I thought back to my metals class when my teacher talked about the level of accuracy which is necessary for particular jobs, and how you wouldn't build a house while measuring lengths in micrometers just as you wouldn't build an engine while measuring in inches. (I forget the name of the principle, I was in Jr. High.)
What really drove that point home was when somebody plugged an ethernet switch into itself a few weeks after I'd done a moderately good wiring job in our closet and I had to tear it all out because I couldn't even get to our management console on the switch to see which port was causing the traffic storm. (Netgear FSM750S if you want to know.) So, just as many people had pointed out, my zip-tied bundle of cables did me no good and they are now hanging off the side of the switch in a mess, no longer matched up to the numbers on the patch panel.
I guess it really does matter what kind of job you're doing... If you're not going to be changing anything, zip tying it all up might make sense. They staple AC wires inside the walls of houses, so I'm sure we can find an instance where zipping up cables would be appropriate. For me though, I'll take velcro and a slight mess.
... I feel I am the worst wiring technician on the planet. All I have to do is look at a cable to get it tangled!
when the article is asking us to go look at some nice racks?
I know this is not going to be a popular opinion but..
Tightly bound cable bundles at the rack are NOT helping anyone but the anal person looking at the pretty pictures. Try troubleshooting or replacing a wire in that bundle at the rack. A rack is a dynamic environment, that is why there are jacks there! If it was not meant to be dynamic, why even use jacks at the rack? Just hard wire everything. If your rack is attached to the floor, movement and cable chafing is not a problem either. If you have to spend more then 5 minutes to get the bundle the way it looked before you replaced a wire at the rack level, you are wasting every ones time including your own to get it to look absolutely perfect. There is NOTHING wrong from a technical standpoint by using the plain old cable management hooks on the front of a typical rack that the cables route through, each wire does not need to be zip tied or Velcro every few inches and each wire spreading off of the bundle with a cable tie for each one, in fact, you can cross over the width of a typical 19 inch rack without the need for any additional bundling other then standard wire management trays and hooks. Side rack mounting depends on type of management you have for that, I've seen some better then others.
Like I said, my opinion is not going to be a popular one but can someone give me a technical reason why every rj45 plug in something like a 24 port blade needs to tied individually or even in groups of two? Is that "unsafe"? Is it a hazard in your environment? If so, what the hell is going on in your equipment room and why do you not have a door on your rack? Is it harder to track down then a huge bundle 20 deep and zip tied to 10ft lbs every 3 inches?
Oddly enough, I've seen many installations where the rack looked pristine but the out of sight areas or covered parts for the actual runs like under floor or overhead in partially covered trays or inside the rack vertical sections looked like spaghetti. If your goal is neatness and you justify the clean rack area for some technical reason, what is your excuse for the other areas that are out of normal sight looking like crap, do those technical reasons for a pristine rack not apply to areas others can not easily see? In order to get the rack to look nice, the extra cabling is balled up and hidden elsewhere. It does not make sense.
For reference, I do neat work now and I've had to replace and re bundle cables and wires inside nuclear reactor instrumentation control panels and rack mounted electronic instrumentation shelves using nylon string and shellac so I am very familiar with the concept and the goals of proper wire management.
Check out this crazy yellow one. And it's yellow! :)
From AQFL.
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
What you're after is called control panel trunking. For an example what it looks like, go to http://rswww.com/ and enter "PVC open slot trunking" in the search box (I tend to use mainly black 50x50mm). This is, incidentally, also the trick I have seen on some rack systems to keep it looking tidy. That doesn't mean it IS tidy (matter of definition), but it looks that way :-).
:-)
Cut it to size and drop on the floor behind equipment or under your desk, or screw down where required. Best use separate ones for mains power and signal cable, but I've managed with all-in-one as well (not with audio, though).
The idea is to route the cable straight in, route out at exit point and roll up the excess inside the tray. However, if you're thinking of doing that with power cable you better make very sure that you don't go near the rated capacity of the cable (sensible in any case), so a cable powering an electric heater is probably not a good candidate.
After you're done, pop on the lid and it all looks wonderfully tidy. Yet, if you want to change something, all you do is rip the lid off and change. I've once had a workroom where I'd simply run a trunk all the way round the room, just above the skirting board, and my desk has one just under the edge, plus one running down a leg. That was a real hi tech solution, it was fitted using double sided sticky tape
In an office you just use sensible colours, so I guess blue is probably not the best solution . It's basically just following some visual tricks, the eye ignores straight lines and regular patterns.
Caveat: I repeat, this makes it LOOK tidy. It can still become a complete nightmare inside, and I've found that at occasions it's simply better to rip the lot out and start again.
So there. It's not as hard as it looks - you just have to know which tools to use..
Insert
I suppose you could use them to tie yourself to your chair and therefore not trip over stuff.
(no I don't know either how they could help)
OTOH there are some U shaped nails that are wide enough for CAT5 cabling. I've used those before.
May contain traces of nut.
Made from the freshest electrons.
What would be the fun in trying to locate a cable in one of those perfectly tied, will-you-marry-me-now bundles? Where is the CHALLENGE, the spirit of the techie?
I'm a comp.science person, so we don't do such mundane tasks, but for you lowly H/W freaks I suggest that cabling be done a little worse to make your miserable lives a little more interesting.
I think balance is best; those ultra-tidy racks would also win prizes in a contest for Obsessive Compulsives. Of course, maybe they are in the avionics bay of the space shuttle and need to be zipped down... or maybe they have bad infestation of those naughty server-room elves...
Somewhere in the fricking middle is best; don't zip-tie stuff that makes re-working twice the tsak it need be. Unlss your GOAL is to make re-wroking twice the task it should be...
The discussions of maintainability reminded me of a funny story.
At the first company I started, we had an excellent ops fellow who did all our wiring. The racks were immaculate, on par with the the winners in the competition. We never found maintainability a major factor, as things were wired right, and patch panels routed things as changes dictated.
However, on one occasion, I do remember his obsessive compulsive approach annoying. We were doing some moving around, so he was coming in and out of my office every few minutes for various changes, as was I. I typically don't screw in my monitor (or other cables), because, well, I don't need to, and I often change things around. Anyhow, the work I was doing that day involved plugging the monitor into a few different units to check things out. At one point, I couldn't remove it from the PC. It had been screwed in. I undid it, and moved it to the next PC I was checking, went to the bathroom. When I came back, I couldn't remove it, it had been screwed in again. Every time my employee walked by, he was screwing the monitor cable in tight, the way it "should be." This went on for about four or five times. The fact he even spotted it was amazing, much less the inability to walk by it without "fixing" it.
Love many, trust a few, do harm to none.
again Yes! Like others have said, if you work in an enviroment where you have to deal with machine faults etc (I'm actually a broadcaster but its increasingly server based now and the same principles apply) it makes it so much quicker and easier if the rack is wired neatly and in such a manner that you can trace cables (numbering helps too!). Unfortunatly what I've found when Broadcast and IT kit start to combine is people can't be bothered to make CAT5 cables and so the premade patch cables get used, for a temporary bodge this is fine however on permenant installations having cables the correct length and with appropriate numbering makes life so much easier!
The racks shown in the article look nice and all, but I didn't see any labels. They get an 'F'. Its one thing not to have labels at IDFs, but not on server racks - ever. At least one of those looked like server racks.
"We are all geniuses when we dream"
- E.M. Cioran
Yeah. If only there were some magical technology that could notice that the induced EMF is in the same phase on the two legs, and with some sort of amplifier, find a differential signal that would remove it.
If I ever invent one, I'll call it a magic-signal-sorter.
Stop making your own cables for production use! Stop being part of the problem that we have to come fix! Buy factory-made and certified cables that come with a warranty. You people are keeping people like me employed because of your save a buck attitudes. Then again I suppose that's a good thing, for me.
Yeah, because the cables in that winning system were all store bought - NOT! How hard is it to test a cable after you've terminated it to the exact length you need for the neatest, tidiest install possible? I used to do a lot of that, and I would have to re-terminate maybe one out of every fifty cables, it's not that hard.
If you want a really nice looking install, you need to terminate yourself.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Ha! What a crock of shit. Cables have always and will always move frequently if for no other reason than people can not afford (or will not buy) enough switchports for every drop. We had a new building wired not too long ago. In total there were over 1500 drops in the building. We had about 450 switchports total to support 400 users. Businesses however are extremely dynamic. One day they're using a conference room for a temporary training lab and need 12 working drops (wireless is not an option). The remodel X offices per week (I think it's a requirement from their charter), requiring additional drops on different walls. They move one department from one area to another. Of course one of the departments is the dev team which has numerous drops per cube. The point is wiring closets are never, EVER stagnant. Wiring closets are more comparable to a living breathing being. Hell it can develop an attitude. Wire neatly. Punch everything down and use cross connects. Don't try to be a wiring zealot. It won't work.
For truly permanent installs, like wiring from the comms room to offices, then skilled (and tested) field terminations are pretty much the only option. There is way too much slack if you factory terminate end-user wiring.
For data centers, all the really good installs I have seen use factory-made trunks going to patch panels interconnected with factory-made patches. This gives you MUCH more flexibility than point-to-point cabling, and makes box installs go much faster when you can just break out a crate of more-or-less appropriate-length patch cables.
Ideal in my mind for a data center: Server -> factory patch of a good length (use several different sizes and select whichever is appropriate) -> mini patch-panel -> factory trunk -> central patch panel -> factory patch -> whatever... (usually your switch). This involves more cables than a field-terminated point-to-point setup, but it makes changes SO much easier.
I can say that for fiber, you should only use field-terminated cables if absolutely necessary. It is simply too easy to screw up optic fiber terminations. 90% of the cabling issues I deal with in my line of business (enterprise storage support) are because of poor field-terminated 50u (or *shudder* 62.5u) cabling.
SirWired