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4.1.14 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 over-current protected according to national/international regulations.
Short-circuit protection:
The frequency converter 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 frequency conveter. The frequency converter provides full short-
circuit protection in case of a short-circuit on the motor output.
Over-current protection
Provide overload protection to avoid fire hazard due to overheating of the cables in the installation. The frequency converter is equipped with an inter-
nal over-current protection that can be used for upstream overload protection (UL-applications excluded). See par. 4-18
Current Limit
. Moreover, fuses
or circuit breakers can be used to provide the over-current protection in the installation. Over-current protection must always be carried out according
to national regulations.
Non UL compliance
If UL/cUL is not to be complied with, we recommend using the follow-
ing fuses, which will ensure compliance with EN50178:
P110 - P250
380 - 480 V
type gG
P315 - P450
380 - 480 V
type gR
UL Compliance
380-480V, frame sizes D, E and F
The fuses below are suitable for use on a circuit capable of delivering 100,000 Arms (symmetrical), 240V, or 480V, or 500V, or 600V depending on the
drive voltage rating. With the proper fusing the drive Short Circuit Current Rating (SCCR) is 100,000 Arms.
Size/
Type
Bussmann
E1958
JFHR2**
Bussmann
E4273
T/JDDZ**
SIBA
E180276
JFHR2
LittelFuse
E71611
JFHR2**
Ferraz-
Shawmut
E60314
JFHR2**
Bussmann
E4274
H/JDDZ**
Bussmann
E125085
JFHR2*
Internal
Option
Bussmann
P110
FWH-
300
JJS-
300
2061032.315
L50S-300
A50-P300
NOS-
300
170M3017
170M3018
P132
FWH-
350
JJS-
350
2061032.35
L50S-350
A50-P350
NOS-
350
170M3018
170M3018
P160
FWH-
400
JJS-
400
2061032.40
L50S-400
A50-P400
NOS-
400
170M4012
170M4016
P200
FWH-
500
JJS-
500
2061032.50
L50S-500
A50-P500
NOS-
500
170M4014
170M4016
P250
FWH-
600
JJS-
600
2062032.63
L50S-600
A50-P600
NOS-
600
170M4016
170M4016
Table 4.2: Frame Size D, Line Fuses, 380-480V
Size/
Type
Buss-
mann
PN*
Rating
Ferraz
Siba
P315
170M4
017
700A,
700V
6.9URD31D08A0
700
20 610 32.700
P355
170M6
013
900A,
700V
6.9URD33D08A0
900
20 630 32.900
P400
170M6
013
900A,
700V
6.9URD33D08A0
900
20 630 32.900
P450
170M6
013
900A,
700V
6.9URD33D08A0
900
20 630 32.900
Table 4.3: Frame Size E, Line Fuses, 380-480V
4 Electrical Installation
VLT HVAC Drive High Power Operating In-
structions
66
MG.11.F3.02 - VLT
®
is a registered Danfoss trademark
4