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the frequency converter as possible. The signal line should use shielded wire, the shielding layer
should be single ended grounding, and should be as far away from the inverter and its input and
output lines as possible. If the signal wire must intersect with the strong current cable, the two
should be kept orthogonal.
(2) High frequency noise filters (ferrite common mode choke) are installed at the root of the
input and output sides of the inverter, which can effectively suppress the RF interference of the
power line.
(3) The motor cable should be placed in the barrier with larger thickness, such as in the pipe
with thickness (more than 2mm) or embedded in the cement tank. The power line is sheathed in
the metal pipe and grounded with the shielded wire (the motor cable adopts 4-core cable, one of
which is grounded on the inverter side and the other side is connected to the motor shell).
Avoid parallel wiring or binding of strong and weak current wires. It should be far away from
the installation equipment of frequency converter as far as possible, and its wiring should be far
away from the input and output lines of frequency converter. Shielded wire is used for signal
line and power line. For the equipment with strong electric field or magnetic field, pay attention
to the relative installation position with frequency converter, and keep the distance and
orthogonality.
5-1-2. Field wiring and grounding
1. The cable (U, V, W terminal outgoing line) from the frequency converter to the motor should avoid parallel
wiring with the power line (R, S, T or L, N terminal input line) as far as possible. Keep a distance of more than
30cm.
2. The three motor wires of inverter output U, V and W terminals shall be placed in metal tube or metal wiring
slot.
3. The control signal line shall be shielded cable, and the shielding layer shall be connected with the PE end of
the frequency converter, and the single end grounding near the side of the frequency converter.
4. The PE end grounding cable of frequency converter shall not borrow the grounding wire of other equipment,
but must be directly connected with the ground.
5. The control signal line shall not be parallel to the strong current cable (R, S, T or L, N and U, V, W) for short
distance wiring, and shall not be bundled together. The distance above 20 ~ 60 cm (related to the strong current)
shall be maintained. If you want to intersect, you should cross each other vertically, as shown in the figure
below.
6. Weak current grounding wires such as control signals and sensors must be grounded independently from
strong current grounding wires.
7. It is forbidden to connect other devices on the power input terminal (R, S, T or L, N) of frequency converter.
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