Power Failure Did Busy-Out; Power-Failure Transfer Telephone - AT&T MERLIN LEGEND Release 3.1 System Manager's Manual

Power-Related Hardware

Power Failure DID Busy-Out

Your AT&T technician may program the PFT jack on a ground-start or module to
automatically short the busy-out wire pair associated with a group of DID trunks
when a power failure occurs. This signals the local telephone company that the
DID trunks are out of service.

Power-Failure Transfer Telephone

A power-failure transfer (PFT) telephone is a single-line telephone connected to
a PFT jack on a 400, 400/GS/LS, 408, 408 GS/LS, 408 GS/LS-MLX, 800, 800
GS/LS, or 800 GS/LS-ID module. In the event of a power failure, the system
shuts off and the PFT telephone automatically connects to an associated
outside line for making and receiving calls.
When your system was planned, your AT&T representative made sure that it had
a module to support one or more PFT telephones in case of an emergency. For
more information, contact your AT&T representative.
NOTES:
1. The PFT jack does not operate unless a power outage occurs or the power
supply units are turned off.
2. The PFT telephone can be any basic single-line telephone; a single-line
telephone that is connected to an MFM cannot be a PFT telephone.
3. If rotary lines/trunks are in the system, you must use rotary telephones
(500MMs recommended) as PFT telephones.
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System Components