Lucent Technologies 60V Small Broadband Power System J85500Q-1
7 - 2 Maintenance
Issue 4 October 1998
4. Verify the BD setting on the replacement ACU.
5. Insert the replacement unit.
6. Disconnect thermal probes and adjust the rectifier output
voltage to 81.72 volts dc.
7. Replace the thermal probes.
8. Replace the BPS faceplate.
Fan Maintenance
The expected life of the power unit fans at 25°C (77°F) is seven
years. The fans in CPS power modules may be replaced in the
field without opening the power unit. When one or both fans fail,
the power unit shuts down and issues a power unit alarm and a
thermal alarm.
Two approaches can be taken to fan maintenance. The first
approach is to replace the fan cradle assembly on a routine basis
every five 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
Figure 7-1: BPS with ACU (EBM1) Partially Removed
