Specifications

FOM-E1/T1 Ver. 2.0 Detecting Errors 4-1

Chapter 4

Troubleshooting and

Diagnostics

This chapter describes the following FOM-E1/T1 diagnostic functions:

• Front panel LED indicators

• Alarm relays

• Diagnostic loopbacks.

The chapter also provides tips on troubleshooting and frequently asked

questions.

4.1 Detecting Errors

Front Panel LEDs

The front panel LED indicators indicate the status of the FOM-E1/T1. For a

description of LED indicators and their functions, see

Chapter 3

Alarm Relays

FOM-E1/T1 has dry contact alarm relays. The following fault conditions trigger the

major and minor alarm relays:

• A major alarm is initiated when E1/T1 electrical input drops below G.703

electrical levels, or the bit error rate at the fiber optic interface is higher than

-6

• A minor alarms occurs when an Alarm Indication Signal (AIS) is received at the

E1/T1 electrical or fiber optic interfaces.

For information on the DB-9 connector pins used for the alarm relays, see

Appendix A

, table A-2.

When connecting an external alarm-monitoring device, do not exceed the

maximum rating of the alarm relay contacts (1A, 60 VDC, 30 VAC).

Note