Semiconductor Fuses (F1) And Fuse Holders For Armature Circuit - ABB DCS880 series Hardware Manual

Conclusion for the field circuit
Basically, similar conditions apply for both field and armature circuit. Depending on
the converter used (half-controlled bridge, fully controlled bridge), some of the fault
sources may not always be applicable. Due to special system conditions, such as
supply via an autotransformer or an isolating transformer, new protection conditions
may occur.
The following configurations are very often used:
In contrast to the armature circuit, fuses are never used on the DC side of the field
circuit, since a fuse trip might lead to additional damage e.g. small, but long-lasting
overcurrent, contact problems, explosions, fires, etc.
Semiconductor fuses F3.1 (super-fast acting) should be used, in case of similar
conditions compared to the armature circuit (4-Q operation). E.g. protection of the
field circuit and the field winding.
Fuses F3.2 and F3.3 are used as line protectors and cannot protect the field
supply unit. Only pure HRC fuses or miniature circuit-breakers must be used.
Semiconductor fuses will be tripped, for example, by the transformer's inrush
current.
F3.2
F3.3

Semiconductor fuses (F1) and fuse holders for armature circuit

The converters are subdivided into two groups:
- Unit sizes H1, H2, H3 and H4 with rated currents up to 1000 A require external
fuses.
- In unit sizes H5, H6, H7 and H8 with rated currents from 900 A to 5200 A, branch
fuses are internally installed (no additional external AC or DC fuses are needed).
The fourth column of the table below assigns the AC fuse to the unit. In case the
converter should be equipped with DC fuses, use the same type of fuse as on the
AC side.
3ADW000462R0101 DCS880 Hardware Manual e a
ND30 /
F3.1
built-in
SB_SIC_001_a.ai
F3.1
ND30 /
built-in
F3.1
SB_SIC_001_a.ai
Configuration for field circuit
2
Configurations for field circuit
2
2
Planning the electrical installation
25