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Chapter 5—Electrical installation
POWERXL SERIES VFDS
MN040060EN—September 2020 www.eaton.com
International EMC protection cable requirements
The screened cables between the variable frequency drive
and the motor should be as short as possible.
•
Connect the screening, on both sides and across a large
area (360° overlap), to the protective earth (PE). The
power screening protective earth (PES) connection should
be in the immediate proximity of the variable frequency
drive and directly on the motor terminal box.
•
Prevent the screening from becoming unbraided, e.g.,
by pushing the opened plastic sheath over the end of
the screening or with a rubber grommet on the end of
the screening. As an alternative, in addition to a broad
area cable clip, you can also twist the shielding braid at
the end and connect to protective ground with a cable
clip. To prevent EMC disturbance, this twisted shielding
connection should be made as short as possible.
•
Screened three- or four-wire cable is recommended for
the motor cables. The green/yellow line of a four-wire
cable connects the protective ground connections
from the motor and the variable frequency drive and
therefore minimizes the equalizing current loads on the
shielding braid.
•
If there are additional subassemblies in a motor feeder
(such as motor contactors, overload relays, motor reactor,
sinusoidal filters or terminals), the shielding of the motor
cable can be interrupted close to these subassemblies
and connected to the mounting plate (PES) with a large
area connection.
Unsheilded or sheilded connection cables should not be any
longer than about 200 mm.
Table 24. Environment EMC levels
➀
.
Cable Type
Category C2
Category C3
Category C4
b
Line voltage/mains 1
1
1
Motor cable
3
c
3
3
Control cable
4
4
4
otes:
N
➀
For EMC C2&C3 requirements on DM1 series drive, use
provided core with input&output wires going through it
once. Refer to section “FR1 mounting instructions”, “FR2
mounting instructions”, “FR3 mounting instructions”, ”FR4
mounting instructions”.
➁
For installations in IT systems, it is necessary to modify
the EMC protection to EMC level C4. See the following
page for the procedure.
➂
360° earthing of the shield with cable glands in motor end
needed for EMC Level C2. See the following page for the
procedure.
➃
Control cable needs to follow the section “Screen earth
kit” to grounding.
Table 25.
Motor power cable EMC guidelines.
Item
Directive
Product
IEC 61800-2
Safety
UL 61800-5-1, IEC/EN 61800-5-1
EMC (at default
settings)
Immunity (EMS): IEC/EN 61800-3, 2nd environment
Radiated and Conducted emissions (EMI): IEC/EN 61800-3
230/480V Series:
Category C1: is possible with external filter connected to
drive. Please consult factory
Category C2: with internal filter maximum of 5 m motor cable
length
Category C3: with internal filter maximum of 25 m motor
cable length
Table 26. Cable categories.
Cable
category
Description
(All cables are rated for the specific operating voltage)
1
Intended for fixed installation.
2
Symmetrical power cable equipped with a concentric protection
wire.
3
Symmetrical power cable with compact low-impedance shield.
Recommended cable transfer impedance of 1–30 MHz max. See
figure below.
4
Screened cable equipped with compact low-impedance shield.
Figure 9. Cable description.
PE Conductor
and Shield
Shield
PE Conductor
