PairGain PG-Flex, Руководство пользователя

Страница: 9 / 168

1
This section contains a general overview of the PG-Flex 24 channel universal subscriber carrier
system, and provides descriptions of the Central Office (CO) and Remote Terminal (RT)
equipment.
Introduction
PG-Flex is a small-capacity, universal subscriber carrier system supporting up to 24 channels on
two pair of existing copper wires. A PG-Flex system is comprised of one line unit and one (or more)
channel units at both the Central Office and the Remote Terminals (Figure 1). The Central Office
Terminal (COT) line unit takes the CO battery and converts it to the voltages necessary to operate
the COT line units and channel units, and supplies power to the RT equipment.
The CO-side of a PG-Flex system mounts into either a 19- or a 23-inch COT shelf. The 19-inch
shelf supports up to two systems, while the 23-inch shelf supports up to four systems. An alarm
unit or Pair Gain Test Controller (PGTC) interface unit (common to all systems installed in a shelf)
provides an interface for maintenance alarm relays and metallic access to the remote subscriber
lines. The plain old telephone service (POTS) channel units use a pulse code modulation (PCM)
encoding scheme that allows high speed modem and group 3 facsimile operation on all channels.
Each channel unit can provide four (4) or eight (8) channels depending on the service offered.
Services offered are:
• POTS Loop Start
• POTS Ground Start
• Integrated Services Digital Network (ISDN)
The RT-side of a PG-Flex system mounts into an FRE-765 RT enclosure. The RT enclosure
supports one system, which includes one line unit and up to three channels units. The channel units
must be the same type of card as the channel units installed at the CO.
PG-F
LEX
S
YSTEM
O
VERVIEW