1.3.5 Fuses
Branch circuit protection:
In order to protect the installation against electrical and
fire hazard, all branch circuits in an installation, switch
gear, machines etc., must be short-circuited and
overcurrent protected according to national/international
regulations.
Short circuit protection:
Danfoss recommends using the fuses mentioned in the
following tables to protect service personnel or other
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
motor or brake output.
Overcurrent protection:
Provide overload protection to avoid overheating of the
cables in the installation. Overcurrent protection must
always be carried out according to national regulations.
Fuses must be designed for protection in a circuit capable
of supplying a maximum of 100,000A
rms
(symmetrical),
480V maximum.
Non UL compliance:
If UL/cUL is not to be complied with, Danfoss recommends
using the fuses mentioned in the below table, which will
ensure compliance with EN50178/IEC61800-5-1:
In case of malfunction, not following the fuse recommen-
dation may result in damage to the frequency converter.
FC 51
Max. Fuses UL
Max. fuses non UL
Bussmann Bussmann Bussmann Littel fuse
Ferraz-
Shawmut
Ferraz-
Shawmut
1 X 200-240V
kW Type RK1 Type J Type T Type RK1 Type CC Type RK1 Type gG
0K18 - 0K37 KTN-R15 JKS-15 JJN-15 KLN-R15 ATM-R15 A2K-15R 16A
0K75 KTN-R25 JKS-25 JJN-25 KLN-R25 ATM-R25 A2K-25R 25A
1K5 KTN-R35 JKS-35 JJN-35 KLN-R35 - A2K-35R 35A
2K2 KTN-R50 JKS-50 JJN-50 KLN-R50 - A2K-50R 50A
3 x 200-240V
0K25 KTN-R10 JKS-10 JJN-10 KLN-R10 ATM-R10 A2K-10R 10A
0K37 KTN-R15 JKS-15 JJN-15 KLN-R15 ATM-R15 A2K-15R 16A
0K75 KTN-R20 JKS-20 JJN-20 KLN-R20 ATM-R20 A2K-20R 20A
1K5 KTN-R25 JKS-25 JJN-25 KLN-R25 ATM-R25 A2K-25R 25A
2K2 KTN-R40 JKS-40 JJN-40 KLN-R40 ATM-R40 A2K-40R 40A
3K7 KTN-R40 JKS-40 JJN-40 KLN-R40 - A2K-40R 40A
3 x 380-480V
0K37 - 0K75 KTS-R10 JKS-10 JJS-10 KLS-R10 ATM-R10 A6K-10R 10A
1K5 KTS-R15 JKS-15 JJS-15 KLS-R15 ATM-R15 A2K-15R 16A
2K2 KTS-R20 JKS-20 JJS-20 KLS-R20 ATM-R20 A6K-20R 20A
3K0 KTS-R40 JKS-40 JJS-40 KLS-R40 ATM-R40 A6K405R 40A
4K0 KTS-R40 JKS-40 JJS-40 KLS-R40 ATM-R40 A6K-40R 40A
5K5 KTS-R40 JKS-40 JJS-40 KLS-R40 - A6K-40R 40A
7K5 KTS-R40 JKS-40 JJS-40 KLS-R40 - A6K-40R 40A
11K0 KTS-R60 JKS-60 JJS-60 KLS-R60 - A6K-60R 63A
15K0 KTS-R60 JKS-60 JJS-60 KLS-R60 - A6K-60R 63A
18K5 KTS-R60 JKS-60 JJS-60 KLS-R60 - A6K-60R 80A
22K0 KTS-R60 JKS-60 JJS-60 KLS-R60 - A6K-60R 80A
Table 1.3 Fuses
Quick Guide VLT Micro Drive Quick Guide
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