Nortel Networks 1750 manual HSSI WAN interface card

96Appendix A Technical specifications

Table 33 X.21 cable pinouts (continued)

Standard-			Standard-
wired end		Pair number	wired end
28-pin male	Signal name	and conductor	15-pin male	Notes
1	SHIELD	Pair 14A	1	At each end, the cable
				shield and connector shell
				must connect to pin 1 of the
				connector.
				Do not interconnect Shield
				to Signal Ground because
				these are separate signals.
7	SIGNAL GROUND	Pair 14B	8	Wires 13B and 14B
				connect to pin 8 in the
				15-pin connector.
				Do not interconnect Shield
				to Signal Ground because
				these are separate signals.

HSSI WAN interface card

The HSSI WAN interface card has a 50-pin SCSI II female connector that provides the signals to interface to a T3 modem or modem eliminator. The following figure shows the HSSI WAN interface card.

Figure 34 HSSI WAN interface card

CS460003A

Included in the accessory box is a cable that maps the T3 signals out to a 50-pin SCSI II male connector.

The following table provides the T3 cable pinouts.

Table 34 T3 cable pinouts

50-pin SCSI male	Signal name	50-pin SCSI male
1	GND	1
2	RCB	2

NN46110-316 03.01