
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 adjustable frequency drive (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 breakdown internally in the
adjustable frequency drive.
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 overcurrent 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 breakdown in the
adjustable frequency drive.
10.3.2 Recommendations
WARNING
In case of malfunction, not following the recommendation
may result in risk to personnel and damage to the
adjustable frequency drive 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 provided they limit the
energy into the adjustable frequency drive to a level equal
to or lower than the Moeller types.
If fuses/circuit breakers according to recommendations are
chosen, possible damage to the adjustable frequency drive
will mainly be limited to damage 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 adjustable frequency
drive voltage rating. With the proper fusing the adjustable
frequency drive 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 Instruction
Manual
MG33AM22 - VLT
®
is a registered Danfoss trademark
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