Power Failure Backup; Figure 2-37: Power Failure Backup Flowchart - NEC Xen alpha Installation Manual

Power Failure Backup

Operation in the Event of a Power Failure
In the event of a power failure, the optional built-in batteries or external batteries
(locally provided) provide full backup of the service of the system for a period
dependent on the system configuration and service conditions. Two Power Fail
Transfer (PFT) Single Line telephone Interface Circuit are built into the KSU. The KSU
connects each Single Line Telephone directly to CO/PBX line (01 and 02) to allow
origination and termination of calls. (Refer to Figure 2-37: Power Failure Backup
Flowchart, Pg 76.)
Note 1:
Note 2:
Note 3:
76

Figure 2-37: Power Failure Backup Flowchart

All calls in progress are interrupted when switch over is made to connect the
Power Fail Transfer Single Line Telephones directly to the CO/PBX Line 1.
This occurs after backup batteries have expired.
If the power switch of the KSU is in the OFF position, the system will not
automatically restart service.
When power is restored, calls in progress on the Power Fail telephones will
not be interrupted.
Installation Manual, Chapter 2 – KSU Installation
A6-506000-642-01(8508), Release 6.0, November 2003