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Table 125 e1 bit error rate threshold settings, Table 125 "e1 bit error rate threshold – Nortel Networks Circuit Card 311 User Manual

Page 299

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Man-Machine E1 maintenance interface software

299

Note: The error-rate threshold for a level 2 alarm must be greater (a
smaller power of 10) than for a level 1 alarm. Remember that the
numbers being represented are negative numbers. Since 3 represents
–3, and 4 represents –4, 4 represents a smaller number than 3 does.

Table 125
E1 bit error rate threshold settings

Alarm threshold bit

errors per second in

power of 10

Threshold to set

alarm

Allowable Duration

Periods

10

-3

2,000/ second

1-21 seconds

10

-4

200/second

1-218 seconds

10

-5

20/second

1-2148 seconds

10

-6

2.0/second

1-3600 seconds

10

-7

2.0/10 seconds

10-3600 seconds

10

-8

2.0/100 seconds

100-3600 seconds

10

-9

2.0/1000 seconds

1000-3600 seconds

The duration value is set in seconds and can be set from 1 to 3,600 seconds
(1 hour). This duration value indicates how long the alarm condition must
last before an alarm is declared. Low bit-error rates (10

7

through 10

9

) are

restricted to longer durations since it takes more than one second to detect
an alarm condition above10

6

. Higher bit-error rates are restricted to shorter

durations because the MMI error counter fills at 65,000 errors.

If the

Set Clearing (S C)

"Enable Self Clearing" option is set, the alarm

indications (LEDs and external alarm contacts) is automatically cleared after
the specified period, or duration, expires. Otherwise, the alarm continues
until the command

Clear Alarm (C A)

is entered.

When an alarm is cleared, all activity caused by the alarm indications is
cleared:

the external alarm hardware is deactivated (the contact normally open
is reopened)

the LED goes out

an entry is made in the alarm log of the date and time the alarm was
cleared

carrier-fail line supervision ceases (for alarm level 2 only)

If self-clearing alarm indications are disabled, carrier-fail line supervision
terminates when the alarm condition has ceased, but the external alarm
contact and faceplate LED remain active until the alarm is cleared.

Nortel Communication Server 1000

Circuit Card Reference

NN43001-311

01.04

Standard

Release 5.0

23 May 2008

Copyright © 2003-2008, Nortel Networks

.