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Structured the Home... or dra In August SILICON CHIP we looked at Structured Cabling and its place in the modern office. Did you know that exactly the same principles apply to the data and communications wiring in your own home? By Ross Tester T his all started not long ago when my daughter and son-inlaw bought their first “real” house. All very exciting, of course, after living in a third-floor unit since they were married (not to mention better for me – how I hated those six flights of stairs!). It is a reasonably old house and while a bit of spit and polish made it perfectly liveable, it suffered from 20th century wiring. Most obvious was the lack of power outlets – for example, just two in the kitchen (and one of those was for the ’fridge). But just as noticeable (at least to me after my adventures last month with structured cabling systems and the “miniLAN”) was the complete lack of communications and data cabling. Of course, neither of these problems were overly surprising. Back when this home was built they only put one power outlet in each room because there wasn’t the proliferation of appliances and devices of today. And as for data, well, home computers hadn’t even been invented yet; TV was in its infancy (no family had more than one, if that) and what was a VCR? It’s only in recent times that builders of new homes have started to put in almost as many power outlets as PIC TO COME Superb under-floor access meant no crawling around – in fact, a ladder was needed to reach the floor above! Inset is a close-up of one side of the garage: lying on the floor is just some of the dangerous wiring we removed. Ignore the rest of the junk – the garage proved too tempting to store stuff while moving in... 10  Silicon Chip Cabling for agging home wiring, kicking and screaming, into the 21st century needed (Murphy’s law again – the number of power points in any given room is always n-1, where n is the required number). And it’s only in very recent times – if at all – that builders of new homes have started to worry about data and communications cabling. As we said last month, while building is in progress is by far the best time to take future needs into consideration. An extra couple of hundred dollars’ worth of cable and sockets while access is dead easy could save a lot of heartaches in the future – when it’s not! But this was not a new house. Sure, they were planning on giving it a bit of TLC – as much as their budget would stretch, that is. But I thought it would be a good opportunity to put my new-found knowledge on structured cabling to the test, in a domestic (as distinct from a business) situation. What’s more, it could be grist for the SILICON CHIP mill: perhaps readers would like some ideas of what they could do themselves? “Would you like to have your home data and communications wiring updated?” I asked. “How much will it cost?” was their reply. “Not much at all,” I said. “Well, if you think so… but we really need someone to have a look at the power wiring as well...” Now I have a mate who’s a licensed electrician and Austel-approved cabler and he owed me a favour or two. For the cost of any materials, he would do what was required if I supplied the labour. And we had a long weekend coming up! Access One of the reasons I had “volunteered” to help out the kids was the outstanding under-floor access. The house is built on a slope with much of the under-side occupied by a double-width, very long garage (you’d fit six cars in it if you tried). No crawling around in the dark in this place. That’s probably fortunate because the house is built in an area known locally as “spider hill” – it contains possibly the largest concentration of funnel-web spiders in Sydney! Anyway, my mate and I reconnoitred the place to check out what we had in store. Power wiring What we found first made us shudder. While some of the place was wired well, it was obvious that someone who really didn’t have a clue had “had a go” at installing some new wiring. There was building cable simply draped from bearer to bearer (hey, cable clips cost money!) and, far worse, ends of cables hung down in various places protected with nothing more than insulation tape. It didn’t take too long to identify where these dangerous cables were connected and simply remove them altogether. That done, we proceeded to re-cable where necessary and install new power points as required. We also took the opportunity to remove the existing mishmash of light fittings (which my daughter hated) and replace them with new ones. That wasn’t too much of a challenge – but the fitting in the lounge room with its completely exposed live wiring and connectors, well that made us think twice. This place has very low ceilings – a tall person could easily reach up and touch live terminals! Needless to say, that problem was fixed. There was one problem which wasn’t fixed: a mysterious architrave switch just inside the back door. Try as we might, we could not work out what this switch did nor where the wires travelled. No, it’s not an external light – we found the cabling and switch for that elsewhere. Nor is it a two-way switch for something else – we couldn’t make it do anything. About all we know is that it has active and neutral coming in, switched active and neutral going out – but to where? Light cabling is in the ceiling but this place has a flat metal roof only 150mm above the ceiling, so there is no access. One of these days, when the rusting roof is replaced, we might find out! Until then, we decided to leave well enough alone. Data/communications wiring The power side completed, we Someone had tried their hand at wiring in the past: building wire simply draped over bearers, live wires hanging down “protected” only by insulation tape... it was enough to make you shudder! October 2000  11 of the house. It disappeared through a hole drilled right through the wall (ugh!) into a wall plate outlet simply lying on the floor in probably the worst position in the lounge room. That would have to go. Before ripping the cable out, we decided to check the signal level and to our surprise found rock-solid, ghost free reception (this area is not renowned for good signal, especially on VHF). That was fortunate because they had two (possibly three) TV sets and two VCRs to connect. We might even be able to get away with splitters and no amplifier. But we would still have to run new coax cable to where it was required. Audio Just like the "miniLAN" in our last issue, the heart of a structured cabling system for the home is a patch panel. This is the KRONE Broadway, complete with smoked perspex cover. Clipsal’s “Starserve” is somewhat similar – see separate panel. now turned our attention to the data and communications side which, of course, is the main reason for this story. The previous occupants of the home ran a business and had three tele-phones, all on their own exchange lines (no, we don’t think they were SP bookies!). There were two cables coming in from the street, one a single pair and the other a four-wire. The first line had been properly installed, nicely cable-clipped to a floor bearer all the way until it disappeared up a hole to go to a phone socket on a skirting board above. The other cable was much like the power wiring we had found, simply draped over bearers and terminated in a pair of Telecom 610 sockets also hanging in thin air below a floor joist. There were a couple of holes drilled straight through the floorboards above which had probably once had cables going through them to sockets upstairs, but they weren’t there now. TV Next it was time to look at the TV installation. There was an old VHF antenna mounted on a weird contraption of pipework on the roof with a balun and 75Ω cable running down the side This version of the Broadway, shown here with the outer cover removed, is set up for five zones (it can handle up to ten). To add extra zones or services it is simply a matter of cutting out the label and inserting extra sockets/connectors (the metalwork underneath is pre-punched). 12  Silicon Chip Another surprise was a pair of figure-8 cables which ran from the front of the house to the back, ending up in a flexible conduit which disappeared under the back wall. We managed to trace this out to the pool area where it ended in bare wires, again hanging in midair. The other end, under the house, was also hanging in midair but immediately above were two more holes drilled straight through the floor. We surmised that these cables once connected to a hifi system with speakers connected near the pool “on demand”. At least we hoped that’s what they were for! OK, it was time to gather our thoughts. We had repaired, removed or replaced any mains wiring which needed it. We had three telephone Opening the door reveals a range of punch-down sockets for incoming and outgoing services, along with a Disconnect Module (a punchdown connector for incoming ’phone lines) and two splitters/combiners for RF (coax) services. Fibreoptic is also available – nice to know for future expansion. My “mud map” of the kid’s house with all of the services, both incoming and distributed, to be handled by the stuctured cabling system and coax cable. This is to a large degree a “wish list” with all the things they could think of that they might like in the future (like four TV sets – and a pool camera: they don’t even have a pool yet!). lines coming in from the street, only two of which would ever be used (one for phone, one for fax/modem). We had a pair of figure-8 cables which we presumed were audio. And we had an old TV antenna with a short down-lead ending in the wrong place. Taking stock Now we had to look at their data and communications requirements. They wanted TV outlets in the lounge-room and two of the three bedrooms – with the option of an outlet in the other bedroom if possible. They wanted to be able to dub from one VCR to the other, even though they were to be many metres apart (no, of course they wouldn’t record any copyrighted material. Nobody does that!) They wanted the existing phone socket moved, another socket on that line in the main bedroom and one of the spare lines moved to the computer desk in one of the bedrooms for the fax and modem. And then they remembered they wanted cabling placed to allow a security system to be installed and, while we were at it, what about the audio cabling? Could it go elsewhere in the house as well so that extra speakers could be installed later? Now this was starting to become a pretty tall order. There would be cabling everywhere – phone lines, data lines, TV coax, audio cables, security cables. It could easily turn into a nightmare. Structured cabling Then my mate said “What about running as much as possible in Cat5?”. At the time I only had a vague idea what Cat5 was – the cabling used for computer networks. (All this was before we covered the MiniLan system last month.) But running phones, data, audio, security, perhaps even video, all on Cat5? “No problem,” he said. I hate it when someone says no problem. That’s usually when the problems start. But he assured me that what he was proposing was not only perfectly practical, it was the most economic method, certainly the most flexible and also the neatest into the bargain. It’s a system called structured cabling, which simply means installing a cabling system independent of the services it carries, the equipment it serves or even the building layout. Most modern office buildings are being wired using structured cabling and now it’s the turn of the home. (See the article on Structured Cabling in last month’s SILICON CHIP). What it means is that you install cabling to cover just about anything that you can think of, now and in the future. One end is terminated in a patch panel of some description (we’ll describe this shortly) while all the other ends, wherever they go to, end in jacks mounted on wall plates. The wiring is done using Cat5 caOctober 2000  13 The wallplate fits a standard mounting block or plate. Here we are using a plasterboard mount with a standard Clipsal/ HPM 4-way plate. Yeh, we could have moved the desk first! ble, which contains four unshielded twisted pairs (UTP), each wire colour coded to its mate. That means at any wall outlet you could have up to four different devices connected, depending on which pair they connect to. A voice telephone, for example, would normally be connected to the centre pair of connectors (4 & 5) which are wired to the blue and blue/white pair. While a standard ’phone usually has four wires connected to it, only two are used. The same naturally applies to a fax machine connected to a telephone line. But if you wanted to connect, say, computers over a network (standard Ethernet) you would use two pairs, 1/2 and 3/6. Note that you don’t need to separate the individual conductors out to separate wall jacks – you arrange the cable so that the RJ-45 plugs connect to the appropriate terminals inside the jacks. If you want to run two services from the same wall jack, devices called “splitters” (logically enough!) are used. Until now, Cat5 has been used almost exclusively for phone and data. But that’s starting to change, with audio being “piped” around using spare Ensure you have plenty of cable – an extra metre won’t make any difference to performance and the extra can always be pushed back into the wall cavity. Cat5 pairs and lately, we’ve seen that even some video signals have been sent along Cat5. While Cat5 can be used to distribute entertainment-type video/RF signals, so far that hasn’t happened in a big way. By entertainment-type signals we’re talking about TV signals from your antenna and composite video such as that from a video cassette recorder. But “low resolution” video from such things as the cheap CCD security cameras now being sold everywhere (eg, as door viewers, baby minders, pool watchers, etc), well, that is certainly a proposition over Cat5. One of the major difficulties in using Cat5 for high resolution (and for that read high bandwidth) signals is just that: the Cat5 must have the bandwidth required. These days, the better stuff does but you also need a high bandwidth balun to convert the signals from the near-universal 75Ω impedance standard of TV’s, VCR’s etc to the 100Ω impedance of Cat5. And these aren’t the type of devices you’re going to pick up at your local lolly shop. (If you’d like more information on distributing video on Cat5, cable manufacturer Belden have a very good paper on their website – www.belden .com/products/tpvutp85.htm). Not being too adventurous, we decided to stick with tried-and-trusted coax cable. To send entertainment-type video or RF signals over any distance, good quality 75Ω coax cable is needed. RG59 has been commonly used in the past and is quite satisfactory in strong signal areas but for optimum results, a premium coax such as RG6 is preferable. It is double the price but it’s worth it. Naturally, RG59 and RG6 need to be terminated in either “F” or “TV” (ie Belling-Lee) connectors, not RJ45 jacks! We mentioned audio a while ago. We're definitely NOT talking high level (speaker level) hifi. Cat5 cables, even if paralleled, simply don’t have enough copper in them to avoid big I2R losses over any appreciable distance. Background music (ie, low level), perhaps even a pair of speakers on the patio or near the pool might be one thing but running a decent level into hifi speakers over any significant distance is a different thing entirely. In this case, you need to run nice big cables, the bigger the better. (We'd even baulk at running ‘ordinary’ figure-8 over a distance – so-called ‘monster cable’ would be our choice.) The patch panel Front and rear views of the 4-way plates we decided to use in each of the bedrooms. These are standard Clipsal/ HPM plates intended for light switches – the connectors are “snap in” types. 14  Silicon Chip Let’s now go back to the other end of the cable which, as we mentioned before, terminates at a patch panel. What a patch panel does is allow you, via patch cords, to connect anything to anything. If you want a telephone moved from one room to another, simply Note the hinged doors on the modular sockets (we removed one for the pictures) and the protective dust boots over the F-connectors. connect the appropriate patch lead and disconnect the other. If you want to network two computers, simply patch them together (more than two computers on an Ethernet network usually require a hub). Want music out by the pool instead of on the patio? Swap the patch lead from patio to pool. Hopefully, you are now starting to get some idea of the flexibility that structured cabling allows. Assuming of course that the device is correctly wired, when you wire the Cat5 conductors to the appropriate pins on the RJ45 plug the device automatically connects, via its patch cord, to the right terminals. Plug a phone in and it connects to pins 4 and 5 and ignores the rest. Plug a computer in and it connects to pins 1, 2, 3 and 6 and ignores the rest. And so on. The finished data/phone/video wallplate. It is placed about 400mm away from the power outlet with a wall stud separating them – just for extra safety. the least important steps in the overall task. Most important is a plan, drawn out, of what you want and where you want it – both now and in the future. When building new premises, structured cabling is easy – it’s usually just a matter of sending the cable through the same ducts or wall cavities as the other wiring or pipe work to just about everywhere possible! Retrofitting a house is slightly more difficult, especially if access is a problem. As we said before, though, this house had no difficulties in this regard. OK, what did we want? Emanating from the patch panel, the wish list looked something like this: (1) Telephone/fax lines from the patch panel to six locations – all bedrooms, the lounge, kitchen and one in the workshop downstairs. (2) Data lines to network computers in three locations – each of the bedrooms. (3) Speaker lines to two extra locations (not counting the main hifi speakers) – pool area and workshop. (4) Intercom lines between kitchen /lounge and workshop. (5) Security system lines to every room but not necessarily in same locations as other lines . (6) RF (TV antenna) lines (75Ω cable) to all bedrooms and the loungeroom. Going to the patch panel, we needed: Going to Broadway We used a proprietary panel, the KRONE Broadway. It is specifically designed for structured cable wiring in homes. There are other possibilities, of course: KRONE’s MiniLAN, which we looked at last month, is a good example. The main effective difference between the Broadway and the MiniLAN is that the Broadway has RF (coax) distribution capabilities built in, while the MiniLAN is more intended for office applications – but either could be used to do a similar job. Other manufacturers have similar devices – Clipsal, for example, market the “STARSERVE” system (see panel) and doubtless there are others. The plan of attack The actual wiring of the home for structured wiring is arguably one of Using the KRONE “punchdown” tool to connect Cat5 cable to the various connectors. It is quite OK to connect your own LAN and data wiring, along with any other services you are going to run over Cat5. However, it is illegal for anyone but Austel-licenced installers to wire telephone/fax cabling. October 2000  15 (1) Telephone connection – from street – 2 lines – one phone, one fax. (2) Audio (speaker) input – from stereo system (2 pairs). (3) RF input (75Ω cable) from TV antenna on roof. (4) Intercom control unit. (5) Security System control unit. (6) 2 x video camera (baby minder and pool watcher) input, and (7) After all this was done, they decided to get OptusVision on!! Doing it! Now that we knew where we wanted our cables to run it would simply be a matter of determining the shortest distance between point A and point B, running out the cable and fixing it to joists or bearers with cable clamps, right? Well, it’s not quite that simple. For a start, to minimise hum and noise pickup, if at all possible you need to avoid running the cables in close proximity and especially close and parallel to mains wiring. This is less of a problem with shielded coax cable but good practice says you should follow the same rules with coax as you do for Cat5 (which can certainly be affected). So the shortest path may not be the best path – but the shortest practical path is. Where you must cross mains cabling, it should be done at right angles if possible. It’s important for your safety that all cabling, mains, Cat5 and anything else, be properly installed with all insulation intact. When Cat5 needs to turn a corner, it should be on a radius, not a sharp 90° bend. And when terminated to RJ45 jacks, that must be done correctly to minimise NEXT, or “near end crosstalk”. Even stripping back too much outer sheath at a termination point can increase NEXT and threaten the performance of the whole system. NEXT performance is particularly susceptible to conductor untwisting – no more than 13mm should be untwisted in a connection. For this reason, the outer sheath is left intact right up to the point of termination. Cat5 connections are not soldered. Most are made with the aid of a “punchdown” tool. Better versions of this tool strip the wire, push it into the socket, force connection and cut off the excess all in one action. About 600mm of cable should be left at each wall outlet (eg, stuffed back into the cavity) to allow termination and possible later amendment or repair. At the patch terminal end, you should leave double this length on all cables, neatly bundled and laced together, for the same reason. All this information, though, should be known to your licensed Austel installer. If you are not connecting tele-phone wiring (eg, if you are only wiring for a network or audio, etc) you do not need to use an Austel in- staller but you should make yourself conversant with Cat5 wiring requirements and practices first. The Namlea Data Systems catalog is a good place to start! Coax cabling Having finished all the Cat5 wiring and terminating it to its appropriate jacks or blocks, it was then a simple matter to install all the coax cable. We bought a 100m roll of coax, even though we figured we’d need much less. Buying in bulk saves a fair bit of money – and it’s always handy to have some spare cable on hand. (RG6 normally sells for about $1.60 per metre but a hundred meter roll can be bought for under $100, so if you need more than about 60m you’re in front). Like Cat5, coax cable does not take too kindly to very sharp bends – a smooth radius will help avoid any disturbance of the cable which can affect its impedance and performance. The coax cables terminated in “F” connectors, either plugs (which went into their respective sockets in the patch panel) or wall sockets mounted on the same plates as the RJ-45 jacks. These really do require the use of a special crimping tool which, fortunately, my mate had. (Fortunately for me, that is because a good coax cable crimper will set you back about $60 or so). Don’t try to use one of the elcheapo lug crimping tools – it will only ruin your plugs and probably not work anyway. Having punched down or crimped the Cat5 and coax respectively, it was then simply a matter of connecting the cables to their appropriate positions inside the Broadway. On the wall socket ends we bought some F to TV (or “Belling Lee” adaptors and used the standard cables which came with the TVs and VCRs. With 20/20 hindsight, we might have been better to use the TV-type sockets on the wall plates instead of F connectors, which would have saved a few bob in adaptors. Patching it up Another look inside the Broadway, this time showing more clearly the 8-way RF splitter (right side) and the Disconnect Module (bottom of picture) which is where your incoming telephone service lines are terminated. An Austel-licenced person must wire the phone lines but you may wire data and RF services yourself. 16  Silicon Chip Assuming you have wired to plan, now all you need do is patch between the various RJ45 plugs using patch leads. Cat5 patch leads come in a variety of lengths and colours – you should use the same coloured lead as the RJ45 jack to save confusion. While this feature has concentrated on the KRONE Broadway, there is a very attractive alternative from Clipsal. Here is just a broad outline – further details from www.clipsal.com.au Like the Broadway, the Clipsal STARSERVE consists of Cat5 data cable, RG6 video cable, wall outlets and a Central Control Panel. As the STARSERVE Network System is modular, you can increase your Home Office options with the addition of modules that simply plug into the basic system, making it possible to start with a simple system and upgrading it as finance allows. By adding devices to the Central Control Panel, the system can be configured to carry a wide range of video and data services around the home. While the STARSERVE also allows a number of personal computers to be networked, perhaps the most obvious difference between this and the Broadway is that STARSERVE also appears to be designed more with video, security systems and remote control in mind (along with the other “standard” features). Video modulators permit up to eight external sources to be added to the normal television service. Therefore, security cameras, VCRs or laser disks can be connected to the system and viewed on any television in the house. STARSERVE enables you to create a sophisticated video distribution system. Infrared targets, when used in conjunction with RF/IR plates, enable remote control operation of a single TV, VCR or CD from any location.You can watch and control a video located in your lounge room from the bedroom by simply pointing a remote control at the infrared target and the control will travel via the cabling to your VCR or Laser Disk. STARSERVE Features:  Network two or more computers in different rooms to each other or to printers via a hub, just like like in an office.  Have a number of televisions connected to a single video recorder or Pay-TV source, which can be controlled using the remote control from any location in the home.  Have two different telephone or fax lines, each with up to eight outlets around the home or office. Telephone lines can be linked to the security system to provide a call out facility in the event of a break in.  Include security cameras or external video sources into the system, and playback from any TV in your home.  Upgrade the system easily at any time. As STARSERVE is modular, you can start off with a basic system and add components when required in the future. There is some argument as to whether there is any convention about colours of RJ45 jacks/plugs (eg, blue for voice [ie phone] and red for data, etc). Your Austel-licenced installer may be quite adamant about which is used for which – but then again, may not. Probably the best piece of advice we can give is to be consistent – if only for safety and reliability. By the way, we did use that colour code above, with white used for everything else. Just as making an overall plan was necessary to make sure you kept track of what went where, labels on patch panel jacks are a must. Also, if you didn’t see our article last month, there is a big difference between Cat5 cable for permanent installation (eg, in the wall) and Cat5 for patch leads. The first, normally called LAN Cat5, has a single solid conductor while patch Cat5 leads have multiple, flexible conductors. The modular plugs and jacks which attach to these must be the right ones for that type of cable (ie, you cannot use modular plugs designed for LAN Cat5 on Patch Cat5 and vice versa). By the way, patch Cat5 cables also require a special crimper for their plugs. You are much better off buying pre-made patch leads or having someone make them for you if you need non-standard lengths. Your patch panel will almost certainly come with some patch leads. Just as certainly, there won’t be enough – or they will be the wrong colours for the services you want to patch! Change your mind? Now that the system is installed, if you change your mind about what goes where, it’s simply a matter of changing a patch lead, not re-routing a cable. All you do is unplug the patch lead from its front panel socket and plug it into where you want it to go. It’s that simple! About now is when you discover how valuable those little labels are alongside each of the RJ-45 jacks or “F” connectors. In a year or so you won’t remember which cable went to where without a label! And should you decide in the future you want different services to run in the Cat5 you’ve installed, that’s easy too – without massive re-cabling. SC For more information: KRONE: PO Box 335, Wyong NSW 2259. Phone (02) 4388 2259, website www.krone.com.au NDS: (Namlea Data Systems) 4/11 Orion Rd, Lane Cove NSW 2066. Phone 9429 0800, website www.namlea.com.au CLIPSAL: (Gerard Industries Pty Ltd) PO Box 103, Hindmarsh SA 5007. Phone (08) 8269 0511, website www.clipsal.com.au October 2000  17