GE Industrial Solutions GPS 4848_100 Users Guide (dual rectifier shelf) - Manual (Page 74)

Galaxy Power System 4848/100 with Dual Rectifier Shelf
11 - 2 Maintenance and Replacement Issue 5 September 2011
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.
Vacant Rectifier
Positions
Vacant rectifier position below or beside the top installed rectifier in this
cabinet may cause over-heating of the installed rectifiers. Immediately
install a replacement rectifier or a Rectifier Shelf Cover / Air Dam into
the vacated position.
Rectifier Shelf Cover
(848680211) Covers both left and right rectifier positions
Air Dam
(CC848809178) Covers the left or right rectifier position
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 fan 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.