Nortel Circuit Card, Installation Manual, Page: 623 / 908

NT8D14 Universal Trunk card Page 623 of 906
Circuit Card Description and Installation
trunks. The class of service determines the operation of the switchable pads
contained in each unit. They are assigned as follows:
• TRC for a 2-wire non-VNL trunk facility with a loss of greater than 2 dB,
or for which impedance compensation is provided, or for a 4-wire
non-VNL facility.
• NTC for a 2-wire, non-VNL trunk facility with a loss of less than 2 dB,
or when impedance compensation is not provided.
See Table 195 for the pad switching control for the various through
connections and the actual port-to-port loss introduced for connections
between the NT8D14 Universal Trunk card and any other port designated as
Port B.
Table 195
Pad switching algorithm
Port B
Port B pads
Universal Trunk
Pads Port-to-port loss (dB)
Transmit
D to A
Receive
A to D
Transmit
D to A
Receive
A to D
Port B to
Universal
trunk
card
Universal
trunk
card to
Port B
IPE line N/A N/A Out Out 0.5 0.5
Universal trunk
(TRC) In Out In Out 1 1
IPE TIE (VNL) In In Out Out 0 0
Note: Transmit and receive designations are from and to the system. Transmit is from the
system to the external facility (digital-to-analog direction in the Universal trunk card). Receive is
to the system from the external facility (analog-to-digital direction in the Universal trunk card).
Note: When Port B is the call originating port. If the Universal trunk card is the originating port,
the UTC pads are out, the Port B (PE CO/FX/WATS) pads are in.