METHOD OF PROCEDURE

Replacing a faulty XM UNIT

 Procedure

2.1   Prerequisites

The following conditions must apply before this procedure can be completed:

See the alarm printout distributed group switch fault The fault-suspected XM designation, defined as plane, individual

row, and individual column, must be known An engineer must be available on site.

2.1.1   Special Aids

Grounding wrist strap (LYB 250 01 or equivalent) Screwdriver (Torx, size T8)

2.2   Actions

2.2.1 Print Unit status

Use command GDSTP .

2.2.2 Block Selected XM Unit

Use command GDBLI.

2.2.3 Block RP

Block the Regional Processor (RP) that belongs to the selected XM unit.

Use command BLRPI .

Note:   See printout DISTRIBUTED GROUP SWITCH UNIT TEST

RESULT received in Step 2.2.1

2.2.4 Print Device Position Data

Use command EXPOP .

2.2.5 Replace Board

Danger

Removing or inserting a board without wearing a grounding wrist strap can damage the equipment.

Caution

Removing a board that does not have the MIA LED lit may cause service interruption.

Disconnect all cables connected to the board selected according to the printout RESULT received in Step 2.2.1 Replace the board and reconnect all previously disconnected cables. Note:  

This step must be performed on site.

2.2.6 Deblock RP

Deblock the RP that belongs to the replaced XM unit.

Use command BLRPE.

2.2.7 Test the Replaced XM Unit

Use command GDTEI .

If the XM unit is faulty still, consult the next level of maintenance support.

Deblock the replaced XM unit.

Use command GDBLE .

2.3 Job completed