How To Use This Document; General Information About Circuit Pack Failures - Northern Telecom BCS35 Replacement Manual

Card replacement guide, distributed processing peripheral

Table of Contents

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Replacing circuit packs

How to use this document

Use the procedures in this document when replacing circuit packs in the

DPP. A general description of each circuit pack is first presented, then the

replacement procedures are given. Next, information about option settings

and circuit pack layout is presented.

Circuit pack failure usually causes the DPP to go to an alarm condition and

switch system control to the standby processor – away from the processor

with the faulty circuit pack. The DPP's response to failure depends on how

the Error Map (ERRMAP) is set up.

Level 0 alarm failures do not cause a processor switch. Level 1, 2, and 3

alarm failures do require a processor switch. Level 1 is the least severe, and

level 3 is the most severe.

Perform a manual processor switch away from the side with the suspected

circuit pack; see Procedure 1–1 . If the DPP is still in PRIME mode, set it

to an ONLY mode before replacing the circuit pack. If a card causes a level

2 alarm in the active processor, the DPP will switch processors if the

standby processor has a level 1 or level 0 alarm or less.

DPP Card Replacement Guide BCS35 and up

Table of Contents

Bcs36