Cisco Systems 2020 manual Closing the Chassis, Applying System Power

Closing the Chassis

Note For ease of maintenance, route cables at the back of the LS2020 chassis in a way that enables you to later remove any access card without disconnecting cables attached to other access cards or fantails.

Closing the Chassis

Before applying system power, check the front and back of the system to ensure that all boards, disks, blowers, bulkheads, filler panels, and covers are in place and secured firmly to the chassis frame. When in place, these items form an enclosure that serves three important functions:

•Prevents exposure to hazardous voltages and currents inside the chassis.

•Confines electromagnetic interference (EMI) within the chassis, a requirement for meeting EMI standards. Emissions from an LS2020 switch that is not fully enclosed may interfere with other ambient equipment.

•Maintains the flow of cooling air through the chassis. Air flow disturbances can result in thermal problems that may induce electronic component failures.

Caution Do not operate an LS2020 switch without first ensuring that all components removed from the installation procedure are restored to their original position in the chassis. The LS2020 switch must operate properly at all times to avoid exposure to hazardous voltages, to confine EMI radiation within the enclosure, and to maintain the proper flow of cooling air through the chassis.

Applying System Power

You can power your LS2020 switch with either an AC or a DC power tray. In addition, you can equip your LS2020 switch with an optional (redundant) power tray of like type (see Figure 2-5).

To power up an LS2020 switch, perform the following steps:

Step 1 If you have an AC-powered system, plug one end of the power cord into the power inlet on the power tray and plug the other end into a dedicated AC power outlet. Note that the power inlet on the rear panel has a wire bail latch for securing the power cord to the chassis. Flip the AC power switch to the left of the power inlet to the up position.

If your system is equipped with a second AC power tray, repeat Step 1 for this tray.

Step 2 If you have a DC-powered system, flip the DC power switch located on the power tray panel to the up position. (This step assumes that your LS2020 switch has already been connected to a DC power source by qualified service personnel or a licensed electrician, as described in the section “Wiring a DC-Powered System”).

If your system is equipped with a second DC power tray, repeat Step 2 for this tray.

Hardware Installation 2-11