Fuses - Danfoss FC 300 Design Manual

6. How to Install

6.3.4. Fuses

Branch circuit protection:
In order to protect the installation against electrical and fire hazards, all branch circuits in an
installation, switch gear, machines, etc. must be short-circuited and overcurrent protected ac-
cording to national/international regulations.
Short-circuit protection:
The adjustable frequency drive must be protected against short circuit in order to avoid electrical
or fire hazard. Danfoss recommends using the fuses mentioned below to protect service personnel
and equipment in case of an internal failure in the drive. The adjustable frequency drive provides
full short-circuit protection in case of a short-circuit on the motor output.
Overcurrent protection:
Provide overload protection to avoid fire hazard due to overheating of the cables in the installation.
The adjustable frequency drive is equipped with an internal overcurrent protection that can be
6
used for upstream overload protection (UL applications excluded). See par. 4-18. Moreover, fuses
or circuit breakers can be used to provide the overcurrent protection in the installation. Overcur-
rent 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 100,000
A
rms
Non-UL compliance
If UL/cUL is not to be complied with, we recommend using the following fuses, which will ensure
compliance with EN50178:
In case of malfunction, not following the recommendation may result in unnecessary damage to
the adjustable frequency drive.
FC 300
K25-K75
1K1-2K2
3K0-3K7
5K5-7K5
11K
15K-18K5
22K
30K
37K
1) Max. fuses - refer to national/international regulations to select an appropriate fuse size.
FC 300
K37-1K5
2K2-4K0
5K5-7K5
11K-18K
22K
30K
37K
45K
55K-75K
116
(symmetrical), 500 V maximum.
Max. fuse size
Max. fuse size
MG.33.B9.22 - VLT
1) Voltage
10A 200-240 V
20A 200-240 V
32A 200-240 V
63A 380-500 V
80A 380-500 V
125A 380-500 V
160A 380-500 V
200A 380-500 V
250A 380-500 V
1) Voltage
10A 380-500 V
20A 380-500 V
32A 380-500 V
63A 380-500 V
80A 380-500 V
100A 380-500 V
125A 380-500 V
160A 380-500 V
250A 380-500 V
® is a registered Danfoss trademark.
FC 300 Design Guide
Type
type gG
type gG
type gG
type gG
type gG
type gG
type aR
type aR
type aR
Type
type gG
type gG
type gG
type gG
type gG
type gG
type gG
type aR
type aR