ABB REC670 Applications Manual page 235

1MRK 511 401-UUS A
Bay control REC670 2.2 ANSI
Application manual
Capacitor Unit
(Can)
IEC09000753 V1 EN-US
Figure 92: 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 where each capacitor element is fused inside the capacitor unit
fused
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 8
Current protection
Rack
IEC09000753_1_en.vsd
229