Hardware Description and Reference for Avaya ... - Avaya Support

Circuit packs, channel service units, and power supplies
Only one 655A supplies ringing to the G650. The power supply in slot 0 in the G650 with an A
carrier address is the default for ringing. The system uses this default 655A unless the 655A
has failed or the software has commanded it to shut down. When a G650 carrier has redundant
power supplies, one supply automatically supplies ringing if the other power supply fails.
A 655A provides ringing to only one G650 carrier. For example, the 655A power supplies in
carrier A supply ringing to carrier A only. Meanwhile, the power supplies in carrier D supply
ringing to carrier D only. If the ring generation in both of a carrier’s power supplies fail, no other
power supply provides ringing for the carrier.
655A replaceable DC-input fuse
The 655A provides a replaceable 25 ADC-input fuse that protects the DC input from reverse
voltage on the -48Vdc input. If reverse voltage is applied to the G650 and 655A power supply,
the 655A fuse will blow open protecting the 655A from damage.
If the G650 will not operate on DC input (only), the fuse should be inspected by removing the
655A power supply from the G650 and inspecting the protection fuse.
The fuse is located on the rear surface of the 655A power supply. A spare fuse is also located
on the rear surface.
676D DC power supply
Note:
Note: This power supply is no longer sold.
A –48 VDC source supplies power to the DC power supply at up to 25 A. The 676C power
supply for the SCC1 Media Gateway, produces DC outputs of +5, –5, –48, and +12 VDC. The
DC outputs are distributed across the cabinet’s backplane to each circuit pack’s slot. The output
value and frequency of the AC ringing voltage depend on the country of use. The power supply
has circuit breakers and electromagnetic interference (EMI) filtering.
982LS current limiter
Note: This
Note:
current limiter is no longer sold.
The 982LS current limiter connects behind the processor circuit pack’s slot only in the processor
port network (PPN) of a DEFINITY SI system. The 982LS provides current-limited accessory
48-VDC, emergency transfer logic, current-limited 5-VDC to trip the main circuit breaker. The
circuit breaker is tripped if high temperature is detected, and duplicated 48-VDC to fans in the
PPN cabinet.
218 Hardware Description and Reference for Avaya Communication Manager