10.3 Fuse Tables
10.3.1 Fuses
All fuses mentioned are max. fuse sizes.
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 shortcircuit and overcurrent
protected according to the 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 in tables 5.3 and
5.4 to protect service personnel or other equipment in
case of an internal failure in the unit. 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. Over current
protection must always be carried out according to
national regulations. The frequency converter is equipped
with an internal over current protection that can be used
for upstream overload protection (UL-applications
excluded). See
4-18 Current Limit
. Fuses must be designed
for protection in a circuit capable of supplying a maximum
of 100,000 A
rms
(symmetrical), 500V/600V maximum.
Non UL compliance:
If UL/cUL is not to be complied with, Danfoss recommends
using the fuses mentioned in table 5.2, which will ensure
compliance with EN50178:
In case of malfunction, not following the recommendation
may result in unnecessary damage to the frequency
converter.
Specifications
VLT
®
AQUA Drive
Operating Instructions
80
MG.20.M8.02 - VLT
®
is a registered Danfoss trademark
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