NOTE
In motors without phase insulation pa-
per or other insulation reinforcement
suitable for operation with voltage
supply (such as an adjustable frequen-
cy drive), fit an LC filter on the FC 300
output.
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 according to national/
international regulations.
Short-circuit protection:
The adjustable frequency drive must be protected against short-circuit 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 used for up-
stream 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. 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 100,000 A
rms
(symmetrical), 500 V maximum.
Non-UL compliance
If UL/cUL is not to be complied with, we recommend using the following fuses, which will ensure com-
pliance with EN50178:
In case of malfunction, not following the recommendation may result in unnecessary damage to the ad-
justable frequency drive.
FC 300
Max. fuse size
1)
Voltage
Type
K25-K75
10A
200-240 V type gG
1K1-2K2
20A
200-240 V type gG
3K0-3K7
32A
200-240 V type gG
5K5-7K5
63A
380-500 V type gG
11K
80A
380-500 V type gG
15K-18K
5
125A
380-500 V type gG
22K
160A
380-500 V type aR
30K
200A
380-500 V type aR
37K
250A
380-500 V type aR
FC 300
Max. fuse size
1)
Voltage
Type
K37-1K5
10A
380-500 V type gG
2K2-4K0
20A
380-500 V type gG
5K5-7K5
32A
380-500 V type gG
11K-18K
63A
380-500 V type gG
22K
80A
380-500 V type gG
30K
100A
380-500 V type gG
37K
125A
380-500 V type gG
45K
160A
380-500 V type aR
55K-75K
250A
380-500 V type aR
1) Max. fuses - see national/international regula-
tions to select an appropriate fuse size.
VLT
®
AutomationDrive FC 300 Instruction Manual
How
to
Install
24
MG.33.A8.22 - VLT
®
is a registered Danfoss trademark.