Illustration 1.7 Tighten support bracket on mains wires.
1.3.7
Fuses
Branch circuit protection
To protect the installation against electrical and fire hazard, all branch circuits in an installation, switch gear, machines etc.,
must be short-circuit and overcurrent protected according to national and local regulations.
Short circuit protection
Danfoss recommends using the fuses listed in Table 1.9 to protect service personnel or equipment in case of an internal
failure in the unit or short-circuit on DC-link. The frequency converter provides full short circuit protection in case of a short-
circuit on the compressor.
Overcurrent protection
Provide overload protection to avoid overheating of the cables in the installation. Overcurrent protection must always be
carried out according to local and national regulations. Circuit breakers and fuses must be designed for protection in a
circuit capable of supplying a maximum of 100,000 A
rms
(symmetrical), 480 V maximum.
UL/Non UL compliance
Use the fuses listed in Table 1.9 to ensure compliance with UL or IEC 61800-5-1.
NOTICE
In the event of malfunction, failure to follow the protection recommendation may result in damage to the frequency
converter.
Fuse
UL Non UL
Bussmann Bussmann Bussmann Bussmann Max fuse
CDS 803 Type RK5 Type RK1 Type J Type T Type G
3x200-240 V IP20
4 TR/VZH028 FRS-R-50 KTN-R50 JKS-50 JJN-50 50
5 TR/VZH035 FRS-R-50 KTN-R50 JKS-50 JJN-50 50
6.5 TR/VZH044 FRS-R-80 KTN-R80 JKS-80 JJN-80 65
3x380-480 V IP20
4 TR/VZH028 FRS-R-25 KTS-R25 JKS-25 JJS-25 25
5 TR/VZH035 FRS-R-25 KTS-R25 JKS-25 JJS-25 25
6.5 TR/VZH044 FRS-R-50 KTS-R50 JKS-50 JJS-50 50
Table 1.9 Fuses
Quick Guide Quick Guide
MG18M102 Danfoss A/S © Rev. 09/2014 All rights reserved. 7
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