Lucent Technologies Galaxy Power System 4848/100
11 - 2  Maintenance and Replacement   Issue 5  June 2000
Requirements, continued
Rectifier With the exception of a fan failure, rectifiers are repaired by 
replacement.
Refer to “Installing or Replacing a Rectifier” and “Removing a 
Rectifier” in this section.
Rectifier Fan 
Assembly
The expected life of the rectifier fans at 25°C (77°F) is approximately 
seven years. The fans in the rectifiers may be replaced in the field. 
Two approaches can be taken to fan maintenance:
• The first approach is to replace the two fans on a routine basis every 
six to seven years; this ensures that the fans do not fail in the field 
under normal operating conditions. This approach is appropriate 
when there are no remote alarm facilities at the site. 
• The second approach, assuming one has remote alarm capability, is 
to wait until the fans fail. The rectifier will safely shut down and 
issue both a fail alarm and a thermal alarm. The two fans can then 
be replaced. Since it is likely that all the rectifiers in that installation 
are of roughly the same age, all rectifier fans at that site should be 
replaced at that time. 
The approach used depends on the location and manning of the site as 
well as the monitoring of alarms used at the site.
Refer to “Replacing the Rectifier Fan Assemblies” in this section.