DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Maintenance Object Repair Procedures
9-376CARR-POW (Carrier Power Supply)
9
Figure 9-21. Power Distribution Unit (J58890CH-1)
Power Backup
The small battery is at the center rear of the Multi-Carrier Cabinet. This eight Amp
Hour (AH) battery is fused for short circuit protection and is charged by the
J58890CH-1. The batteries also contain a thermal sensor that changes the
charging voltage depending on battery temperature.
The small batteries provide short-term battery holdover. If AC power fails, 48
VDC batteries power the system for 10 seconds in a PPN cabinet, for 15 seconds
in an EPN cabinet, and for 10 minutes in the control carrier in a standard
reliability system. The batteries also provide system power for five minutes in the
control carrier in high and critical reliability systems, and for 10 minutes in the
expansion control carrier in the “A” position of an EPN cabinet (Release 5r only).
Figure 9-22
shows the small battery assembly.
