5.2.8 Fuses
A frequency converter that works correctly limits the
current it can draw from the supply. Still, it is
recommended to use fuses and/ or Circuit Breakers on the
supply side as protection in case of component break-
down inside the frequency converter (first fault).
NOTE
This is mandatory in order to ensure compliance with IEC
60364 for CE or NEC 2009 for UL.
WARNING
Personnel and property must be protected against the
consequence of component break-down internally in the
frequency converter.
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 protected against short-circuit
and over-current according to national/international
regulations.
NOTE
The recommendations given do not cover Branch circuit
protection for UL!
Short-circuit protection:
Danfoss recommends using the fuses/Circuit Breakers listed
in and to protect service personnel and property in case of
component break-down in the frequency converter.
Over current protection:
The frequency converter provides overload protection to
limit threats to human life, property damage and to avoid
fire hazard due to overheating of the cables in the instal-
lation. The frequency converter is equipped with an
internal over current protection (
4-18 Current Limit
) that
can be used for upstream overload protection (UL-
applications excluded). 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.
UL Compliance
380-480 V, frame size D
The fuses below are suitable for use on a circuit capable of
delivering 100,000 Arms (symmetrical), 240 V, or 480 V, or
500 V, or 600 V 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 5.9 Frame Size D, Line Fuses, 380-480 V
*170M fuses from Bussmann shown use the -/80 visual indicator, -
TN/80 Type T, -/110 or TN/110 Type T indicator fuses of the same size
and amperage may be substituted for external use.
How to Install
VLT
®
Refrigeration Drive Design Guide
MG16G102 - VLT
®
is a registered Danfoss trademark
67
5
5