Field Wire Connections - Emerson EV2000 Series User Manual

32 Chapter 3 Installation and Wiring
3. Basic methods of suppressing the noise
Table 3-11 Basic methods of suppressing the noise
Noise
emission Actions to reduce the noise
paths
When the external equipment forms a
loop with the drive, the equipment may
suffer nuisance tripping due to the drive's
②
earth leakage current. The problem can
be solved if the equipment is not
grounded.
If the external equipment shares the
same AC supply with the drive, the
drive's noise may be transmitted along
its input power supply cables, which may
cause nuisance tripping to other external
③
equipment. Take the following actions to
solve this problem: Install noise filter at
the input side of the drive, and use an
isolation transformer or line filter to
prevent the noise from disturbing the
external equipment.
If the signal cables of measuring meters,
radio equipment and sensors are
installed in a cabinet together with the
drive, these equipment cables will be
easily disturbed. Take the actions below
to solve the problem:
(1)The equipment and the signal cables
should be as far away as possible from
the drive. The signal cables should be
shielded and the shielding layer should
be grounded. The signal cables should
be placed inside a metal tube and should
be located as far away as possible from
the input/output cables of the drive. If the
signal cables must cross over the power
④⑤⑥ cables, they should be placed at right
angle to one another.
(2) Install radio noise filter and linear
noise filter (ferrite common-mode choke)
at the input and output of the drive to
suppress the emission noise of power
lines.
(3) Motor cables should be placed in a
tube thicker than 2mm or buried in a
cement conduit. Power cables should be
placed inside a metal tube and be
grounded by shielding layer (Motor cable
should be a 4-core cable, where one
core should be connected to the PE of
the drive and another should be
connected to the motor's enclosure).
EV2000 Series Universal Variable Speed Drive User Manual
Noise
emission Actions to reduce the noise
paths
Don't route the signal cables in parallel
with the power cables or bundle these
cables together because the induced
electro-magnetic noise and induced ESD
noise may disturb the signal cables.
Other equipment should also be located
as far away as possible from the drive.
The signal cables should be placed
①⑦⑧ inside a metal tube and should be placed
as far away as possible from the
input/output cables of the drive. The
signal cables and power cables should
be shielded cables. EMC interference
will be further reduced if they could be
placed inside metal tubes. The clearance
between the metal tubes should be at
least 20cm.

3.4.2 Field Wire Connections

Control cables, input power cables and motor cables
should be installed separately, and enough clearance
should be left among the cables, especially when the
cables are laid in parallel and the cable length is big. If
the signal cables must go through the power cables,
they should be vertical to each other.
The motor cables should be derated if they are too long
or their cross sectional area (CSA) is too big. The drive's
cables should be the cables with specified CSA (See
Table 3-1) because the capacitance of the cable to
ground is in proportional to the cable's CSA. If the cable
with big CSA is used, its current should be reduced.
Shielded/armoured cable: High frequency low
impedance shielded cable should be used. For example:
Copper net, aluminum net or iron net.