AT&T Release 2.0 manual Grounding Requirements

Installing the Control Unit

Grounding Requirements

Proper grounding of the installation site safeguards system functioning by protecting the system from the following:

■lightning

■power surges

■power crosses on central office trunks

■electrostatic discharge (ESD)

When installing the control unit, make sure that you meet the following grounding requirements:

■The control unit, the central office trunk protector, and the AC power service panel should be as close to each other as possible.

■Because equipment can be located throughout a building, the National Electrical Code requires that the ground point for the central office trunk protector be bonded to the AC power ground as shown in Figure 2-3.

■The AC outlet and the single-point ground bar must be properly grounded as shown earlier in Figure 2-1.

■Each power supply in the control unit must be connected to the single-point ground bar by a #12 AWG or a #14 AWG solid copper wire. Figures 2-1and 2-3 show this connection.

This wire run should be as short as possible, preferably within 5 ft

(152 cm), not to exceed 10 ft (305 cm). This procedure is described later in this chapter under “Providing the Proper Grounding.”

■The AC outlet must be connected to the 147A protector with #12 AWG or a #14 AWG solid copper wire.

Power and Grounding 2-11