Fuses - Danfoss VLT AutomationDrive FC 300 Operating Instructions Manual

3. How to Install
Term.
3
1) Protected Earth Connection

3.3.4. Fuses

Branch circuit protection:
In order to protect the installation against electrical and fire hazard, all branch circuits in an in-
stallation, switch gear, machines etc., must be short-circuited and overcurrent 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 equip-
ment in case of an internal failure in the drive. The frequency converter provides full short-circuit
protection in case of a short-circuit on the motor output.
Overcurrent protection:
Provide overload protection to avoid fire hazard due to overheating of the cables in the installation.
The frequency converter is equipped with an internal overcurrent protection that can be used for
upstream overload protection (UL-applications excluded). See par. 4-18. Moreover, fuses or circuit
breakers can be used to provide the overcurrent protection in the installation. Overcurrent pro-
tection must always be carried out according to national regulations.
Fuses must be designed for protection in a circuit capable of supplying a maximum of 100,000
A
rms
Non UL compliance
If UL/cUL is not to be complied with, we recommend using the following fuses, which will ensure
compliance with EN50178:
In case of malfunction, not following the recommendation may result in unnecessary damage to
the frequency converter.
26
96 97 98
no.
U V W
PE
U1 V1 W1
PE
W2 U2 V2
U1 V1 W1
PE
(symmetrical), 500 V maximum.
MG.33.A9.02 - VLT is a registered Danfoss trademark
99
Motor voltage 0-100% of mains voltage.
1)
3 wires out of motor
Delta-connected
1)
6 wires out of motor
Star-connected U2, V2, W2
1)
U2, V2 and W2 to be interconnected separately.
®
VLT AutomationDrive FC 300 Operating
NB!
When using motors without
phase insulation paper or other
insulation reinforcement suita-
ble for operation with voltage
supplied from frequency con-
verters, fit aSine-wave filter on
the output of the FC 300.
Instructions