Appendices 27

Standard multimode fiber cabling

For the fiber optic cable models of the Digital Desktop System, the cable interface should be IEEE 802.3z 1000BASE-SX standard multimode fiber optic cabling. Table B.2 shows the minimum link distances that must be supported by cables that are compliant with this standard.

Table B.2: Link Distances

Fiber Type

Modal Bandwidth

Maximum Link Distance

 

 

 

62.5 µm MMF

160 MHz*km

220 meters

 

 

 

62.5 µm MMF

200 MHz*km

275 meters

 

 

 

50 µm MMF

400 MHz*km

500 meters

 

 

 

50 µm MMF

500 MHz*km

500 meters

 

 

 

Premium, or high grade, fiber cables are available, enabling reliable links of 800 meters or greater. If you expect your link to exceed 550 meters, contact Avocent Technical Support for information regarding this higher grade of fiber.

Fiber patch cables used with the Digital Desktop System must have an LC connector on the end that attaches to the Desktop Appliance. Optical connectors selected for use elsewhere in the link, such as at the wall interface, are at the installer’s discretion.

NOTE: To avoid contamination, do not touch the optical surfaces of patch cable connectors with your fingers. The oil from your fingertips will adhere to the connector, impairing link performance.

NOTE: The LC receptacles of the DDP2100 PCI Add In Card and the DDL20xx Desktop Appliance unit are shipped with protective dust covers installed. These protective covers should be retained and reinstalled whenever the fiber cable is removed, or if the product is packaged for storage or shipment.

Cabling installation, maintenance and safety tips

The following is a list of important safety considerations that should be reviewed prior to installing or maintaining your cables:

Keep all CAT 5 runs to a maximum of 100 meters each.

Maintain the twists of the pairs all the way to the point of termination, or no more that one-half inch untwisted. Do not skin off more than one inch of jacket while terminating.

If bending the cable is necessary, make it gradual with no bend sharper than a one inch radius. Allowing the cable to be sharply bent or kinked can permanently damage the cable’s interior.

Dress cables neatly with cable ties, using low to moderate pressure. Do not over-tighten ties.

Cross-connect cables where necessary, using rated punch blocks, patch panels and compo- nents. Do not splice or bridge cable at any point.