Danfoss VLT AQUA Drive FC 202, Руководство по конструкции, Страница: 112 / 218

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Terminals Function
81, 82 Brake resistor terminals
See the VLT® Brake Resistor MCE 101 Design Guide for more details.
N O T I C E
If a short circuit in the brake module occurs, prevent excessive power dissipation in the brake resistor by using a mains switch or
contactor to disconnect the mains from the drive.
10.3.6 Grounding
To obtain electromagnetic compatibility (EMC), consider the following basic issues when installing a drive.
Safety grounding: Note that the drive has a high leakage current and must be grounded appropriately for safety reasons. Apply
local safety regulations.
High-frequency grounding: Keep the ground wire connections as short as possible.
Connect the different ground systems at the lowest possible conductor impedance. The lowest possible conductor impedance is
obtained by keeping the conductor as short as possible and by using the greatest possible surface area. The metal cabinets of the
different devices are mounted on the cabinet rear plate using the lowest possible HF impedance. This avoids having different HF
voltages for the individual devices and avoids the risk of radio interference currents running in connection cables that may be used
between the devices. The radio interference has been reduced. To obtain a low HF impedance, use the fastening bolts of the devices
as HF connection to the rear plate. It is necessary to remove insulating paint or similar from the fastening points.
10.3.7 Safety Ground Connection
W A R N I N G
LEAKAGE CURRENT HAZARD
Leakage currents exceed 3.5 mA. Failure to ground the drive properly can result in death or serious injury.
Ensure the correct grounding of the equipment by a certified electrical installer.
The drive has a high leakage current and must be grounded appropriately for safety reasons according to IEC 61800-5-1.
10.4 Cables
10.4.1 EMC-correct Cables
To optimize EMC immunity of the control cables and emission from the motor cables, use braided shielded/armored cables.
The ability of a cable to reduce the in- and outgoing radiation of electric noise depends on the transfer impedance (Z
T
). The shield of
a cable is normally designed to reduce the transfer of electric noise. However, a shield with a lower transfer impedance (Z
T
) value is
more effective than a shield with a higher transfer impedance (Z
T
).
Cable manufacturers rarely state the transfer impedance (Z
T
), but it is often possible to estimate transfer impedance (Z
T
) by assess-
ing the physical design of the cable.
Transfer impedance (Z
T
) can be assessed based on the following factors:
AJ300847815559en-000101 / 130R0337 112 | Danfoss A/S © 2020.09
Electrical Installation
Considerations
VLT® AQUA Drive FC 202
Design Guide