AT&T 3.0 manual Turning Off the Power, Installing a Copper Shield

Installing the Power Supply

NOTE:

It is not necessary to install ring generators in a new system with new012 (apparatus code 517G13 or later letter) modules or new 008 (apparatus code 5171328 or later letter). If you are upgrading or using older modules, see Maintenance and Troubleshooting.

Turning Off the Power

1 Turn off each power supply.

2 Disconnect all power cords and auxiliary units.

Installing a Copper Shield

The added power supply in each expansion carrier can cause excessive noise in the module occupying the next slot, To eliminate this noise, a copper foil shield is installed over the power supply. These shields and their labels are packaged in the power unit shielding kit included with the expansion carrier.

To install a copper shield, follow the steps below. Refer to Figure 2-6throughout the procedure.

1 Make sure all power is off.

2Place the power supply on a flat surface with the right side up (as viewed from the front edge).

3Wipe the module free of any dust or dirt.

4Peel the backing paper from the smaller copper-foil shield to expose the adhesive.

Check the positioning of the foil shields before sticking them to the side of the module. Once in place, the foil is difficult to remove.

5Position the foil on the upper part of the module and work out any air bubbles as you press the foil firmly in place.

2-20Installing the Control Unit