AT&T 999-507-144 system manual Typical Merlin Plus System Grounding Plan

FIGURE 8-2 Typical MERLIN Plus System Grounding Plan

The control unit, the CO line protector, and the ac power service panel should be as close to each other as possible in order to provide a protected and grounded system. If equipment is spread throughout a building, the National Electric Code requires that the ground point for the CO line protector must be bonded to the ac power ground.

If the ac voltage is subject to heavy transient activity from electrical storms or power company ac power switching, use a T II Powerline Protector (AT&T 8310-001) as the interface to the power source. A phone line surge suppressor provides added protection against lightning, and, if the distance between the equipment and the protector is less than 50 feet, a Coupled Bonding Conductor (CBC) provides additional lightning protection. Use the plan in Figure 8-2 as a guide when verifying that a system is grounded properly.

Warning: Hazardous voltages that may cause death or injury are present during electrical measurement tests. Use great care when working with ac power line voltages.

A properly grounded system has the individual CO line protectors in place and the following ac outlet voltages:

●Hot to ground-about 115 VAC.

●Neutral to ground-less than 2.5 VAC.

●CO protector ground lug to nearest ac outlet of circuit to be used-less than 1 VAC, less than 1 ohm.

8-2Section 8: Installation