7.7 Safety
7.7.1 High Voltage Test
Carry out a high voltage test by short-circuiting terminals
U, V, W, L
1
, L
2
, and L
3
. Energize maximum 2.15 kV DC for
380–500 V adjustable frequency drives and 2.525 kV DC for
525–690 V adjustable frequency drives for one second
between this short-circuit and the chassis.
WARNING
When running high voltage tests of the entire instal-
lation, interrupt line power and the motor connection if
the leakage currents are too high.
7.7.2 Grounding
The following basic issues need to be considered when
installing an adjustable frequency drive to obtain electro-
magnetic compatibility (EMC).
•
Safety grounding:
The adjustable frequency drive has a high
leakage current and must be grounded
appropriately for safety reasons. Comply with all
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. Obtain the lowest possible
conductor impedance 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 prevents having different HF voltages for
the individual devices and prevents the risk of radio
interference currents running in connection cables that
may be used between the devices, as To obtain a low HF
impedance, use the fastening bolts of the devices as HF
connections to the rear plate. Remove insulating paint or
similar obstructions from the fastening points.
7.7.3 Safety Ground Connection
The adjustable frequency drive has a high leakage current
and must be grounded appropriately for safety reasons, in
accordance with EN 50178.
WARNING
The ground leakage current from the adjustable
frequency drive exceeds 3.5 mA. To ensure a good
mechanical connection from the ground cable to the
ground connection (terminal 95), the grounding must be
reinforced in one of the following ways:
•
Ground wire of at least 0.016 in
2
[10 mm
2
]
•
Two separate ground wires both complying
with the dimensioning rules
7.8 EMC-compatible Installation
7.8.1 Electrical Installation - EMC
Precautions
The following is a guideline to good engineering practice
when installing adjustable frequency drives. Follow these
guidelines in compliance with EN 61800-3
First
environment
. If the installation is in EN 61800-3
Second
environment,
industrial networks, or in an installation with
its own transformer, deviation from these guidelines is
allowed but not recommended. See also
chapter 2.3.3 Danfoss Adjustable Frequency Drive and CE
Labeling
chapter 3.5 General Aspects of EMC
chapter 3.5.2 EMC Test Results
, and
.
Electrical Installation
Design Guide
234
Danfoss A/S © Rev. 2014-02-10 All rights reserved.
MG34S222
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Summary of Contents for VLT AutomationDrive FC 300
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