Inter-Tel AXXESS Manual page 117

4.149 LGC -6 cards only work with LGC-D -5 cards (and vice versa). They are not backwards
compatible. LGC -4 and -5 cards only work with either LGC-D -3 and -4 cards.
4.150 If a system is experiencing this problem and if it is equipped with older, unmodified
LGC and/or LGC-D cards, the card(s) may be replaced by contacting Inter-Tel Technical Sup-
port.
I. T1 CARDS (T1CS), E1/PRI CARDS (E1/PRIS), AND T1/E1/PRI CARDS
4.151 The following information is described in this section:
•
T1 Card—T1C (see below)
•
E1/PRI Card (see
•
T1/E1/PRI Card (see
•
Special T1 or E1/PRI Cabling Requirements (see
•
T1C, E1/PRI, or T1/E1/PRI Cards on a Network (see
•
T1 or E1/PRI Network Clock Card—NCC (see
•
T1C, E1/PRI, or T1/E1/PRI Cards Features (see
T1 Cards (T1Cs)
NOTE:
4.152 The acronym for the T1 Card (T1C) should not be confused with the special T1C digital
carrier system (which operates at twice the data rate of the standard T1 carrier system). The T1
Card does not support T1C.
4.153 The term "T1" refers to a specific digital method of transmitting voice and data; it is the
basic 24-channel time-division multiplex (TDM), 1.544 Mb/s pulse code modulation (PCM)
system as used in the United States.
4.154 The T1 standard, which was developed as a method of reducing cabling and increasing
transmission quality between distant central offices, is actually a subset of a multi-level Digital
Signal (DS) scheme. In popular usage, T1 refers to the DS1 rate as transmitted via any type of
media (e.g., copper wire, fiber optics, or microwave).
4.155 Because each T1 span actually consists of 24 individual circuits (or channels) multi-
plexed together, it is often less expensive to purchase a single T1 span than it is to purchase
multiple individual trunks. Each of the 24 T1 circuits can be programmed as a loop start,
ground start, DID, E&M, or OPX trunk (or as unequipped). Any combination is possible.
4.156 "Fractional" T1, often called FT1, is a special T1 service where only a portion of the 24
channels are used and paid for. To implement fractional T1 (if available), equip only those cir-
cuits that are provided.
NOTE:
data. In the future, data transmissions over T1 circuits may also be supported.
4.157 To interface with the public network, each T1 Card is equipped with an on-board-chan-
nel Service Unit (CSU). Because the CSU is on-board, the programmer must select the line
build-out (LBO) attenuation, which is available from the T1 provider.
T1 Cards (T1Cs), E1/PRI Cards (E1/PRIs), and T1/E1/PRI Cards
INTER-TEL
page 2-53)
page 2-54)
T1Cs are not applicable to European systems.
Currently, the T1C and T1/E1/PRI cards are used to transmit voice signals only, not
® ®
AXXESS MANUAL VERSION 11.0 – May 2008
page 2-54)
page 2-55)
page 2-55)
page 2-56)
Specifications
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