VB3/V5/VB5 series inverter
26
Table
Table
Table
Table 2-5
2-5
2-5
2-5 solution
solution
solution
solution for
for
for
for control
control
control
control noise
noise
noise
noise
2-6-2.
2-6-2.
2-6-2.
2-6-2. Local
Local
Local
Local wiring
wiring
wiring
wiring and
and
and
and grounding
grounding
grounding
grounding
(1) The cable connected inverter and motor (cables from U, V, W points) should not parallel with power supply calbe (R, S,
T or L, N terminal input wire). The distance should be more than 30cm.
(2) Inverter’s output cables from U, V, W terminals is recommend to put in metal tube or slot.
(3) Control signal cables should be shield and the shield layer should be connected with inveter’s PE terminal, then ground
the point near the inverter.
(4) The grounding cable of inverter’s PE terminal should be connected to ground directly.It can’t connect to other devices’
grounding cables.
(5) Don’t put the signal cables in parallel with the power cables (R, S, T or L, N with U, V, W) or bundle these cables
together, at least 20~60 cm distance shoule be kept (related with power current), If the signal cables and power cables
needed to be intersected, they should be vertical to each other, as shown in Fig2-12.
Fig.
Fig.
Fig.
Fig. 2-12
2-12
2-12
2-12 Wiring
Wiring
Wiring
Wiring requirement
requirement
requirement
requirement of
of
of
of system
system
system
system
(6) The weak electricity grounding cable such as control signal and sensors should be separated with strong electricity
grounding cable.
Noise transmit
path
Solution
2
When the external equipment forms a loop with the inverter, the equipment may operate incorrectly caused by
leakage current of inverter grounding cable. The problem can be solved if the equipment is not grounded.
3
If the external equipment shares the same AC supply with the inverter, the inverter’s noise may be transmitted
along its input power supply cables, which may cause interference to other external equipments. Take the
following actions to solve this problem: Install noise filter at the input side of the inverter, and use an isolation
transformer or power filter to prevent the noise from disturbing the external equipment.
4,5,6
(1)The equipment and the signal cables should be as far away as possible from the inverter. The signal cables
should be shielded and the shielding layer should be grounded. The signal cables should be located far away
from the input/output cables of the inverter. If the signal cables must cross over the power cables, they should be
placed at right angle to one another.
(2) Install high-frequency noise filter (ferrite common-mode choke) at the input and output of the inverter to
prevent the RF interfere of power lines.
(3) Motor cables should be placed in a tube thicker than 2mm or buried in a cement slot. Power cables should be
placed inside a metal tube and be grounded by shielding layer (Motor cable should use 4-core cable, one of the
cores should be grounded near the inverter and another point should be connected to the motor’s cover).
1,7,8
Don’t put the strong and weak electricity cables in parallel or bundle these cables together. Other devices should
also be away from the inverter.The devices wire should be away from the I/O of the inverter. The signal cables
and power cables should be shielded cables. Devices with strong electric field and magnetic field should be away
and orthogonal from the inverter.
