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- Fuse switch disconnectors
- Switch disconnectors with fuses
- 3KF up to 800 A
- Product description
- Overview of components
- Technical specifications
- Derating values of 3KF fuse switch disconnectors when using SITOR fuses according to IEC constraints
- Derating table for use of SITOR fuses IEC from 32 to 160 A
- Derating table for use of SITOR fuses IEC from 250 to 800 A
- Derating values when using SITOR fuses according to UL constraints
- Derating table for use of SITOR fuses UL from 32 to 160 A
- Derating table for use of SITOR fuses UL from 250 to 800 A
- 3NJ62 up to 630 A
- 3KF up to 800 A
- 8UD1 door-coupling rotary operating mechanisms
Derating values when using SITOR fuses according to UL constraints
The following table shows the permissible load currents of SITOR semiconductor fuses for installation in 3KF SITOR according to UL constraints. The specified values apply to a 3KF mounted in accordance with the test conditions of UL 508 / UL 60947-4-1 (installation in an enclosure) and with connected insulated cables, cross section corresponding to the rated operational current of the 3KF switch disconnector. The specified values apply to use in enclosures that are larger or equal in size to the specified enclosures.
Further derating is necessary if a combination of 3KF and SITOR fuses is used under different conditions that impair heat dissipation.