10.3 Fuse Specifications
10.3.1 Fuses
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
mentioned below to protect service personnel and
property in case of component break-down in the
frequency converter.
10.3.2 Recommendations
WARNING
In case of malfunction, not following the recommendation
may result in personnel risk and damage to the frequency
converter and other equipment.
The following tables list the recommended rated current.
Recommended fuses are of the type gG for small to
medium power sizes. For larger powers, aR fuses are
recommended. For Circuit Breakers, Moeller types have
been tested to have a recommendation. Other types of
circuit breakers may be used provide they limit the energy
into the frequency converter to a level equal to or lower
than the Moeller types.
If fuses/Circuit Breakers according to recommendations are
chosen, possible damages on the frequency converter will
mainly be limited to damages inside the unit.
For further information please see Application Note
Fuses
and Circuit Breakers
.
10.3.3 CE Compliance
Fuses or Circuit Breakers are mandatory to comply with IEC
60364. Danfoss recommend using a selection of the
following.
The fuses below are suitable for use on a circuit capable of
delivering 100,000 Arms (symmetrical), 240 V, 480 V, 500 V,
600 V, or 690 V depending on the frequency converter
voltage rating. With the proper fusing the frequency
converter short circuit current rating (SCCR) is 100,000
Arms.
The following UL listed fuses are suitable:
•
UL248-4 class CC fuses
•
UL248-8 class J fuses
•
UL248-12 class R fuses (RK1)
•
UL248-15 class T fuses
The following max. fuse size and type have been tested:
Specifications
VLT
®
AutomationDrive Operating
Instructions
82
MG33AM02 - VLT
®
is a registered Danfoss trademark
10
10
