ABB REB670 Applications Manual page 229

1MRK 505 337-UUS -
Application manual
Capacitor Unit
(Can)
IEC09000753 V1 EN
Figure 98: Replacement of a faulty capacitor unit within SCB
There are four types of the capacitor unit fusing designs which are used for construction
of SCBs:
Externally where an individual fuse, externally mounted, protects each capacitor unit.
fused
Internally fused where each capacitor element is fused inside the capacitor unit
Fuseless where SCB is built from series connections of the individual capacitor units (that is, strings)
and without any fuses
Unfused where, in contrary to the fuseless configuration, a series or parallel connection of the
capacitor units is used to form SCB, still without any fuses
Section 7
Current protection
Rack
IEC09000753_1_en.vsd
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