Page 11 - Campus Technology, April/May 2017

AV SMARTS
reinstall if you need to swap out a cable. If you’re still using plastic zip ties, make sure they’re trimmed flush, so the rack isn’t full of little razor blades for the poor field tech who needs to service the rack. As cables are bundled, rack designers and installers need to be implementing InfoComm’s best practices of signal separation in racks. Make sure to pay attention to concepts like sufficient service loop length and connector stress when bundling and dressing cables.
As AV over IP designs become more prevalent in modern AV systems, we’re finding larger network switches being installed in AV equipment racks. Using these switches means that rack designers need to pay a bit more attention to cable management. Many network switches have front- facing ports, as opposed to the typical rear-facing ports/ connectors on traditional AV equipment. AV rack designers need to include front-facing patch panels or something like Middle Atlantic’s BR1 brush grommet panel to cleanly get cables out of the rack and into the network switch.
Equipment and Power Management
One aspect of poor rack building that I frequently see is a bunch of small pieces of equipment stuffed in the back of a rack. Just because they don’t have rack ears on them doesn’t mean they should just be free floating inside the rack. Incorporate a couple internal rack shelves to secure
all of your small items like twisted pair transmitters/ receivers, distribution amplifiers, scalers, converters, power supplies, etc.
Related to the cable management discussion above, properly dressing cables inside a rack will also help free up equipment access during those troubleshooting situations. Having clear access to the back of all pieces of equipment is key. That being said, don’t go overboard with horizontal lacing bars, which can make it hard to reach inside the rack.
Power management is often overlooked by rack designers. A few power strips free floating inside the bottom of the rack can make for a messy install. There are quite a few UPS and horizontal/vertical power strip options that can be mounted to the rack to clean things up. Some power distribution solutions even have IP, serial or relay control options to remotely power cycle rack equipment. Specifying the proper number and type of these rack- mounted power distribution units will help you avoid fire code violations like daisy chaining power strips or using extension cords.
Anyone who has designed or built a rack can tell you that those power supply bricks can be a real pain in the rear. They take up room inside the rack and on your power strips, and if you don’t devote a shelf or two to just power supplies, they can really get in the way. Sometimes you
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CAMPUS TECHNOLOGY | April/May 2017
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