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In applications where the motor is used as a brake, energy is generated in the motor and sent back into the drive. If the energy
cannot be transported back to the motor, it increases the voltage in the drive DC line. In applications with frequent braking and/or
high inertia loads, this increase can lead to an overvoltage trip in the drive and, finally, a shutdown.
Brake resistors are used to dissipate the excess energy resulting from the regenerative braking.
The resistor is released based on its ohmic value, its power dissipation rate, and its physical size. Danfoss offers a wide variety of
different resistors that are specially designed for Danfoss drives.
For order numbers and more information on how to dimension brake resistors, refer to
13.2.9 Ordering of VLT® Brake Resistors MCE
, and for more detailed information the
VLT® Brake Resistor MCE 101 Design Guide
.
7.7.6 VLT® Line Reactors
Table 22: VLT
®
Line Reactors
Option name
FC 102
FC 103
FC 202
FC 301
FC 302
VLT
®
Line Reactor MCC 103
x
–
x
x
x
See
for details on using line reactors in load sharing applications.
7.8 Kits and Accessories
7.8.1 Panel Through Mounting Kits for VLT® FC Series Enclosure Sizes A, B, and C (IP21)
The panel through mounting kit are designed for IP21 enclosures and can be used for cooling the heat sink via an external air
stream, or where there is a wish to use a separate air duct. The electronics are sealed from the external air by use of the mounting
flange and sealing gasket. This way the electronics are hosued within the control panel, while the heat sink protrudes through the
panel.
There are specific kits available for enclosure sizes A5, B1, B2, C1, C2. See
13.2.6 Order Numbers for Miscellaneous Hardware
.
The backplate (must be purchased separately) is used if an air duct is not available. Mounted in a duct construction, the built-in fan
can be removed and the cooling air provided by an external fan.
1
2
e3
0b
u3
27
.1
0
A
B
C
Illustration 42: Panel Though Mounting Kit on VLT
®
AutomationDrive FC 302
A
Drive mounted with a panel through mounting kit.
B
Panel through kit with backplate for use with inter-
nal fan.
C
Panel through kit without backplate for installation
in air duct.
1
Mounting flange with sealing gasket.
2
Backplate.
AJ300847815559en-000101 / 130R0337
60 | Danfoss A/S © 2020.09
Options and Accessories Overview
VLT® AQUA Drive FC 202
Design Guide