Cisco Systems OL-12811-01 Channelized E1/ISDN PRI Unbalanced 75-Ohm Network Modules, Function

Connecting Cisco ISDN PRI Network Modules to the Network

Channelized E1/ISDN PRI Unbalanced (75-Ohm) Network Modules

Channelized E1/ISDN PRI Unbalanced (75-Ohm) Network Modules

This section provides information about the following network modules for Cisco modular routers:

•1-port channelized E1/ISDN PRI unbalanced (75-ohm) network module (NM-1CE1U or CPANM-1CE1U) (see Figure 16). This module is also referred to as the 1-portCE1/PRI-U network module.

•2-port channelized E1/ISDN PRI unbalanced (75-ohm) network module (NM-2CE1U or CPANM-2CE1U) (see Figure 17). This module is also referred to as the 2-portCE1/PRI-U network module.

Figure 16 1-Port Channelized E1/ISDN PRI Network Module (Unbalanced)

cE1-U PRI

REMOTE ALARM LOCAL ALARM LOOPBACK CARRIER DETECT

CTRLR 0

EN H8499

CE1/PRI-U port

Figure 17 2-Port Channelized E1/ISDN PRI Network Module (Unbalanced)

cE1-U PRI

REMOTE	ALARM	LOCAL	ALARM	LOOPBACK	CARRIER	DETECT
						CTRLR 1
REMOTE	ALARM	LOCAL	ALARM	LOOPBACK	CARRIER	DETECT

CTRLR 0

EN H8500

CE1/PRI-U ports

CE1/PRI Module Jumper Settings

Jumpers on CE1/PRI modules can be used to connect or disconnect receive shield to ground (see Table 3). The default setting for balanced, 120-ohm CE1/PRI-B modules disconnects receive shield to ground. The default setting for unbalanced, 75-ohm CE1/PRI-U modules connects receive shield to ground. If you are experiencing ground loop problems with E1 cabling, you may want to try changing the jumper settings for the module.

Table 3	CE1/PRI Module Jumpers
CE1/PRI Module Type		Default Setting	Function
Balanced, 120-ohm		2 and 3	Disconnects receive shield from ground
Unbalanced, 75-ohm		1 and 2	Connects receive shield to ground

Connecting Cisco ISDN PRI Network Modules to the Network

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