Co Trunk Cards; Resource Cards - Panasonic KX-TD500 Installation Manual

1.4.2 CO Trunk Cards

Loop Start Central Office Trunk (LCOT) Card;
This card interfaces 8 central office loop start trunks and the TDM bus. It provides 8 CO lines
to the system per LCOT card. With loop start, a line is seized by bridging through a resistance
the tip and ring (both wires) of the telephone line.
Ground Start Central Office Trunk (GCOT) Card;
This card interfaces 8 central office trunks and the TDM bus. It provides 8 CO lines to the
system per GCOT card. This card uses a way of signaling on subscriber trunks in which one
side of the two wire trunk (typically the "Ring" conductor of the Tip and Ring) is momentarily
grounded to get a dial tone.
Note
There are two types of switched trunks one can typically lease from a local phone company —
Loop Start and Ground Start.
You must be careful to order the correct type of trunk from your local phone company and
correctly install your telephone system at your end — so that they both match.
Enhanced Loop Start Central Office Trunk (ELCOT) Card;
This is a version of the LCOT card which supports Caller ID service.
Direct Inward Dialing Trunk (DID) Card;
This card interfaces 4 central office trunks arranged for Direct Inward Dialing (DID) and the
TDM bus.
T-1 Card;
This card interfaces 1 T-1 line and the TDM bus. It is available to connect a T-1 line to the
system per T-1 card. A T-1 line has a capacity of 24 voice conversations.

1.4.3 Resource Cards

Direct Inward System Access (DISA) Card;
This card interfaces 4 central office trunks arranged for Direct Inward System Access (DISA)
and the TDM bus.
System Outline
1.4 Service Cards Description
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