Dual Trunk E1 Router

 

Table 11-2 Network Problems (2 of 4)

 

 

 

Symptom

Probable Cause

Solution

 

 

 

 

 

The NET LED does not

• No incoming signal.

• Run a lamp test from Menu-9,

illuminate.

• Bad LED.

Diagnostics to make sure the LEDs

 

are working.

 

 

 

 

• Make sure the E1 line from your

 

 

service provider is connected to the

 

 

RJ-48C female connector on the

 

 

back of the LRU4240 NTU.

 

 

• Remove the E1 line from the back

 

 

of the LRU4240 and place the E1

 

 

test set in its place. Connect the

 

 

transmit of the E1 test set to the

 

 

receive of the network plug (pins 3

 

 

and 11, 3—tip, 11—ring). If the

 

 

NET LED changes to any color,

 

 

i.e., green or red, contact your

 

 

service provider for assistance with

 

 

cutting over the E1 line.

 

 

• Place the E1 loopback plug on the

 

 

network connector on the back of

 

 

the LRU4240. If it then changes

 

 

color, troubleshoot your test setup.

 

 

• If the NET LED never lights, call

 

 

Black Box Technical Support for

 

 

assistance.

 

 

 

 

The NET LED is constantly red.

• Constant out-of-sync or out-of-

• Make sure the E1 line framing

 

frame on E1.

format matches the LRU4240’s

 

• Misframe/FE.

framing format.

 

 

 

• Carrier has problem.

• Check the LRU4240 for excessive

errors.

• Configuration doesn’t match

• In CRC4-Enabled mode, check for

framing.

CRC and CV; in CRC4-Disabled

 

 

mode, check for CVs only. If

 

excessive errors appear, place your

 

E1 test set or your loopback plug

 

on the RJ-48C or BNC socket on the

 

back of the system to see if the

 

errors stop.

 

• If they do, contact your service

 

provider for assistance.

 

• If the errors do not stop, call Black

 

Box Technical Support for

 

assistance.

 

 

Dual Trunk E1 Router User’s Guide

TECHNICAL: 0118 96 56 000

91

Page 103
Image 103
Black Box LRU4240 manual Network Problems 2