Nortel Networks 553-3001-211 Pad switching algorithm Universal Trunk Port B pads, Trc Ipe Tie Vnl

NT8D14 Universal Trunk card Page 611 of 894

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 190 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 190

Pad switching algorithm

			Universal Trunk
	Port B pads		Pads		Port-to-port loss (dB)
					Port B to	Universal
					Universal	trunk
	Transmit	Receive	Transmit	Receive	trunk	card to
Port B	D to A	A to D	D to A	A to D	card	Port B
IPE line	N/A	N/A	Out	Out	0.5	0.5
Universal trunk	In	Out	In	Out	1	1
(TRC)
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.

Circuit Card Description and Installation