Preparing for Installation

Preventing Electrostatic Discharge Damage

Electrostatic discharge (ESD) can damage equipment and impair electrical circuitry. It occurs when electronic components are improperly handled and can result in complete or intermittent failures. Always follow ESD-prevention procedures when removing and replacing components. Ensure that the chassis is electrically connected to earth ground using an ESD mat or a ground wire. Wear an ESD-preventive wrist strap, ensuring that it makes good skin contact. Connect the clip to an unpainted surface of the chassis frame to safely channel unwanted ESD voltages to ground. To properly guard against ESD damage and shocks, the wrist strap and cord must operate effectively. If no wrist strap is available, ground yourself by touching the metal part of the chassis.

Caution For safety, periodically check the resistance value of the antistatic strap, which should be between 1 and 10 megohms.

Site Requirements

Following are the site requirements for installation.

Environment

Choose a clean, dust-free, (preferably) air-conditioned location. Avoid direct sunlight, heat sources, or areas with high levels of electromagnetic interference (EMI).

Chassis Accessibility

Both the front and rear panels of the concentrator chassis have duplicate status indicators that you may need to monitor. (The traffic LEDS are only on the front panel.) Leave at least 24 inches (60.9 cm) clearance at the rear of the concentrator for easier cabling, service, and access to the LEDs and the reset switch.

Cooling and Airflow

Two fans located at the side of the chassis cool the chassis interior. Both fans always operate. The fans draw air through vents in the left side and exhaust heated air through holes in the right side. If the concentrator temperature exceeds 104°F (40°C) the concentrator status LED will be red. If the interior temperature returns to normal, the status LED will return to its normal green.

Warning To prevent the switch from overheating, do not operate it in an area that exceeds the maximum recommended ambient temperature of 104°F (40°C). To prevent airflow restriction, allow at least 3 inches (7.6 cm) of clearance around the ventilation openings. To see translated versions of this warning, refer to the appendix Translated Safety Warnings.

Power

The source electrical outlet should be installed near the concentrator, be easily accessible, and be properly grounded. Power should come from a building branch circuit. Use a maximum breaker current rating of 20A for 110V or 8A for 230V. Note the power consumption ratings of each unit before you connect to a power source.

Cabling Requirements

Following are the cabling requirements for installation. For pinouts of the following cable types, refer to the appendix "Cabling Specifications."

FDDI

The multimode FDDI connectors on the concentrator accept 62.5/125-micron multimode fiber, or 50/125-micron multimode fiber, with standard FDDI MICs. The single-mode connectors accept 8.7 to 10/125-micron single-mode fiber, with standard FDDI ST-type connectors. Table 2-1 lists FDDI distance specifications and Figure 2-1, Figure 2-2, and Figure 2-3 illustrate single-mode ST, multimode MIC, and multimode SC (low cost) connectors, respectively.

Table 2-1 : FDDI Maximum Transmission Distances

Transceiver Type	Maximum Distance Between Stations
Single-mode--ST	18.6 miles (30 km)
Multimode--MIC	1.2 miles (up to 2 km)
Multimode--SC	1.2 miles (up to 2 km)
Multimode--SC (low cost)	320 feet (up to 100 m)

Warning Invisible laser radiation may be emitted from the aperture ports of the single-mode FDDI card when no cable is connected. Avoid exposure and do not stare into open apertures. To see translated versions of this warning, refer to the appendix Translated Safety Warnings. Following is an example of the warning label that appears on the product:

Warning Class 1 laser product.

Figure 2-1 : Single-Mode FDDI Interface Connector---ST Type

Figure 2-2 : Multimode FDDI Interface Connector---MIC Type

Figure 2-3 : Multimode FDDI Interface Connector--SC Type

CDDI

Check all existing cables for conformance with CDDI/MLT-3 distance requirements and to ensure that you have the proper connectors (modular RJ-45). Following are cable and distance specifications:

• Data-grade UTP---EIA-568, category 5, data-grade cable is required for CDDI installations. The total length of data-grade UTP cable from the concentrator to another concentrator, station, or CDDI switch must not exceed 320 feet (100 m), including patch and cross-connect cables. (See Figure 2-4.)
  

• STP wiring---You must use IBM Type 1 STP wiring for your CDDI installation. The total length of STP cable measured from the adapter or media access unit (MAU) to the concentrator must not exceed 320 feet (100 m). (See Figure 2-4.)