Surge Protectors - AT&T MERLIN LEGEND System Reference Manual

Hardware
146A and 147A Surge
Protectors
5-52 Accessories
Protection from lightning and power surges is needed to safeguard system
functioning.
It is the responsibility of the local telephone company to provide primary
protection on the outside lines at the network interface and to ensure that these
are properly grounded. If the telephone company line protector is
protectors
properly grounded and bonded to the AC power ground, most lightning damage
will be prevented.
The 391A1 power supply module has built-in AC line protection. This built-in
protection handles almost all situations.
Occasionally, additional AC line protection may be needed if the customer is
located in a heavy lightning area. A 147A protector can be connected to the
system to limit surges from the
provides protection for four outside lines. Up to three 146A protectors can be
added to the 147A to provide protection for a maximum of sixteen outside lines.
For more than sixteen lines, additional 147A protectors are required (see
Figure 5-26).
Note: The 147A protector is usually not needed with the 391A1 power supply
module. It may be needed with the older 391A power supply module in high-risk
lightning areas.
Installation instructions are provided with the protectors (CIB 3109 and CIB
3111).
Figure 5-28

Surge Protectors

lines and outside lines. One 147A protector
AC