3Com Router Module Guide
Chapter 3 Multifunctional Interface Modules
3-6
Table 3-3
Pinouts of E&M interface cable (Bell V 4-wire)
Router side
RJ-45 Pin
RJ-45 interface signal
Signal at switch side (Bell V 4-wire)
1
SB (negative power supply)
-
2 E
M
3 RING0
RING0
4 RING1
RING1
5 TIP1
TIP1
6 TIP0
TIP0
7 M
E
8
SG (negative power supply
ground)
-
Note:
z
Interface cables of Router 2-Port FXS/FXO and Router 4-Port FXS/FXO modules are magnetic loop
lines with a ferrite core at one end. To ensure EMC of the Router, connect the end with ferrite core to
the Router.
z
Because it is hard to determine the type of the switch to be connected and its connectors, interface
cables of Router 2 and 4-Port E&M/E&M modules have to be prepared according to the on-spot
conditions or by the user. To ensure the EMC of the Router, install a ferrite core near the connector
of the prepared E&M module interface cable by the router side.
3.1.6 Connecting Interface Cable