Cisco Catalyst 6816-X-LE, Руководство по установке оборудования

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diameter, and dust particles range from a tenth of a micron to several microns in diameter, dust and any
contamination at the end of the fiber core can degrade the performance of the connector interface where the
two cores meet. The connector must be precisely aligned, and the connector interface must be absolutely free
of trapped foreign material.
Connector loss or insertion loss is a critical performance characteristic of a fiber-optic connector. Return loss
is also an important factor. Return loss specifies the amount of reflected light; the lower the reflection, the
better the connection. The best physical-contact connectors have return losses greater than -40 dB, although
-20 to -30 dB is more common.
The connection quality depends on two factors: the type of connector and the proper cleaning and connection
techniques. Dirty fiber connectors are a common source of light loss. Keep the connectors clean at all times,
and keep the dust covers installed when the connectors are not in use.
Before installing any type of cable or connector, use a lint-free alcohol pad from a cleaning kit to clean the
ferrule, the protective white tube around the fiber, and the end-face surface of the fiber.
As a general rule, whenever there is a significant, unexplained loss of light, clean the connectors.
Guidelines
Connectors that are used inside the system are cleaned by the manufacturer and connected to the adapters in
a proper manner. The operation of the system will be error free if the customer provides clean connectors on
the application side and follows these guidelines:
• Does not clean the inside of the connector adapters.
• Does not use force or quick movements when connecting the fiber-optic connectors in the adapters.
• Covers the connectors and adapters to keep the inside of the adapters or the surface of the connectors
from getting dirty when not using the connectors or while cleaning the chassis.
How to Clean the Fiber-Optic Connectors
Use extreme care when removing or installing connectors so that you do not damage the connector housing
or scratch the end-face surface of the fiber. Always install protective covers on unused or disconnected
components to prevent contamination. Always clean fiber connectors before installing them.
Caution
Invisible laser radiation may be emitted from disconnected fibers or connectors. Do not stare into beams or
view directly with optical instruments.
Statement 1051
Warning
Procedure
Step 1
Use a lint-free tissue soaked in 99 percent pure isopropyl alcohol to gently wipe the faceplate. Wait five
seconds for the surfaces to dry, and repeat.
Step 2
Remove any residual dust from the faceplate with clean, dry, oil-free compressed air.
Catalyst 6840-X Switch Series Hardware Installation Guide
75
Module Connectors and Cable Specifications
Guidelines