07.10.14

Technology: Plug and Play AV Racks

Simon-Buddle

By Simon Buddle, Future Ready Homes. I was once told a story by a dealer who was thrown out of a client's house at 9pm on a Friday nig...

Simon BuddleBy Simon Buddle, Future Ready Homes. I was once told a story by a dealer who was thrown out of a client's house at 9pm on a Friday night whilst he was camped out on the lounge floor, laptop and instructions manuals in hand. At the time he thought he was going that extra mile to get the system just how the client wanted it. When he reflected upon it, he realised it looked to the client as if he didn't know what he was doing or how long it would take him. In other words, his installation process did not seem very professional. So there are several aspects to rack construction, testing and installation that must be considered. Not only should it look good and do the job required, its installation must be a smooth and professional process. Looking Good Last year we talked about making racks look good - in fact so good that you would like to show them off. It is pretty easy to make a rack with kit in it look fabulous (I know, perhaps I should get out a bit more, but your love of rackage is why you're reading this, right?) Stacking up a bank of Kaleidescape or Savant products in a 42U cage cannot fail to make a visual impact. Turn the rack around though, and you will see a very different picture. What makes a mess of the rack are all of those damned wires and connectors! Even done well it can still seem like a bird's nest made from spaghetti and old coat hangers, and interconnects on the rack are only half the story - there are all of the cables that come in from the house and adjacent equipment racks. [caption id="attachment_6837" align="aligncenter" width="600"]Have you ever seen anything like this? Have you ever seen anything like this?[/caption] Getting Wires to the Rack Getting the rack wiring looms installed in a neat and tidy fashion is a real headache, so how do you go about it? As with all good installation work, the first element has to be design, and within the design a number of questions need to be asked. For example, for cables that come onto the rack from the house, are you going to put patch bays on the wall and run a wiring loom from the rack? Will those cables come directly up or down onto the racks from basket-style cables trays in the floors or ceilings? If yes, then this poses another question: will the racks be movable after you have finished? [caption id="attachment_6838" align="aligncenter" width="350"]Consider how your cables are going to come onto the rack from the house. Consider how your cables are going to come onto the rack from the house.[/caption] Many years ago I had the pleasure of working with one of the big commercial companies that was installing racks into the Walt Disney Company EMEA headquarters in Hammersmith. This truly was a sight to behold, for coming off the rack were four huge cable looms, with a 128-pin connector on the end. Each one was individually coloured coded to marry up with the socket that had been installed in the wall. Now, it isn't true to say that they just connected all four, and Mickey Mouse appeared before our very eyes, but it wasn't far off. They had successfully achieved the connection (in design and practical terms) between the in-house cables, and translated those onto the inputs and outputs at the back of the rack. [caption id="attachment_6841" align="aligncenter" width="350"]128-pin connector (source: electronicsurplus.com). 128-pin connector (source: electronicsurplus.com).[/caption] Planning the Rack Many companies do great drawing packages with schematics that show all of the in-house cabling. What we often miss out is the final step of landing those cables onto the actual device or product that will use them. We will inevitably need to do this, so why not do that design early in the project as well, thereby preventing that never-ending problem of 'making it up as we go along' at the end? There is another obvious benefit with such detailed design of course, which is it will help to weed out other issues that you may not have thought about, such as power supplies, quantities of inputs or outputs mismatched, signal types, stereo/mono speakers, the list is endless. Remember, early design = greater profit. Building the Rack Should racks be built onsite or offsite? Ideally, we would all choose to build them offsite in a workshop, with all of the relevant tools, finger trunking, cable ties, labels and the like. But that poses another conundrum; how do you get the rack to site? Heavy racks laden with amplifiers and other such goodies are really unwieldy. The health and safety implications are not to be taken lightly either. However, in most instances, it is better to build offsite, as the benefits far outweigh the negatives. [caption id="attachment_6840" align="aligncenter" width="500"]Building the rack off-site has advantages. Building the rack off-site has advantages.[/caption] The aforementioned Disney racks arrived on a specialist vehicle, packed on pallets, with all kit supported and wrapped, and they moved them by hand into the AV rack room onboard soft-wheeled dollies. It doesn't take much to realise that that level of logistics isn’t always viable financially for a small company, but you should still have a full discussion within your team, as again, it might unearth some, as yet, undiscovered problems. Do you have to get the rack up to the first floor, or higher up the building? Are the lifts commissioned yet? Are you allowed to take goods in the lifts? If it is a stone staircase, how you will protect the stone? Remember, the staircase is probably just as expensive as your rack, and it may have been flown in especially from Italy. Will the rack fit on a staircase climber trolley and be manageable by your team? Is the staircase wide enough? Is it worth doing a dummy run with a cardboard box of the same size? All of these questions will feed into your health and safety risk assessment which you should always do for such an arduous task. Remember, task specific planning = greater profit. Testing the Rack If we are able to build the racks offsite, it will require, to some degree, the building of a test rig. To enable the testing we're going to need a screen or two, some speakers, and the data network/control system online. Looking over the system design will quickly show us lots of rooms that have commonality of function. For example; they use speakers from the central rack and video via HDMI to the TV, the control device is a tablet and the room has lighting, heating and door intercom control on the tablet. This would seem to be a good scenario where we could create a test rig and move it from connection (room) to connection on the rack, proving the design, the physical connections and the control programming as we go. This will save hours of time in the client's home. [caption id="attachment_6842" align="aligncenter" width="600"]Proving that everything works with a test rig before installation will save hours of time in the client's home. Proving that everything works with a test rig before installation will save hours of time in the client's home.[/caption] Conclusion Planning, designing and testing a rack before we get to site, so it is plug and play when we get there, has many obvious advantages. It will make us neater, more technically savvy, more efficient, and profitable. But ultimately, it will make us more professional. Simon Buddle is a consultant for Future Ready Homes, a specialist in BMS and ELV services system design. Simon is also a regular contributor to HiddenWires magazine, and the first winner of the CEDIA Region 1 Special Recognition Award. www.futurereadyhomes.com