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Fiber-optic cable cassettes

Fiber-optic retractable cable cassettes offer a unique ability to manage excess cable lengths neatly and with minimal effort. These retractable patch cords provide a variable length of cable from a take-up spool within the cassette. The retractable end transitions continuously to a fixed length of cable attached to the cassette housing. Cassettes can be wall mounted, integrated into transmission systems, or rack mounted. The direct consequence of this cable management approach is enhanced network reliability.

Cassettes may incorporate simplex, duplex, ribbon, or plastic optical fiber. Since glass and plastic optical fibers exposed to sharp bends exhibit increased optical insertion loss, stress birefringence, and ultimately failure, the optical path within the cassette must follow a graceful series of bends to ensure high optical performance identical to standard patch cords. The cassette should maintain the bend radius of the jacketed cable above 1.5 inches at all times.

In most situations, one end of the cable and the cassette are attached to a fixed point, such as a fiber patch panel, wall outlet, or measurement instrument. The other cable end is pulled from the cassette and retained at the desired length. Of course, the cable also may be withdrawn back into the cassette.

In a fiber-to-the-desk application, the cassette may be wall mounted by snapping into a wall mount mini-enclosure (see Photo 1). The mini-enclosure includes an internal fiber racetrack with retaining tabs for storing excess lengths of drop cable and accommodates an SC duplex or LC quad union adapter that interfaces the drop fiber to the fixed cable end of the cassette.

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Note added at 19 mins (2007-09-23 14:29:25 GMT)
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или кабельных кассет, для снятия двусмысленности