8000m Series
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Installation Notices:
1. Correctly ground VFD and other electric devices.
2. Keep the lines of power input and output of VFD away from signal and control
lines, and do not run these two kinds of cables in parallel but in vertical as far as
possible.
3. Shield cable is recommended for output power lines of VFD, or the cable can be
shielded by steel pipe, and the shields must be grounded correctly; It is
recommended to use twisted shield control cable for devices being interfered, and
the shields must be grounded correctly.
4. In case of application with long motor cable which is over 100m, an output filter
or AC output reactor is needed.
7.3.3 Methods for Handling Surrounding Interference to VFD
Normally electromagnetic interferences to the VFD are generated from large
number of devices installed nearby including relays, contactor, or magnetic brakes.
If a VFD is in malfunction by interference, it is recommended to use the following
methods:
1. Install surge arrestor to the part which generates interference.
2. Install filter to the input of VFD, as details in 7.3.6.
3. It is recommended to use shield cable for control and sensing signals, and cable
shields must be grounded correctly.
7.3.4 Methods for Handling VFD Interference to Surrounding Devices
The electromagnetic noises can be classified as two kinds, one is emission, and the
other is conduction interference. These two kinds of interferences can make the
surrounding devices suffering electromagnetic or electrostatic induction, some will
be malfunction due to interference. The following are methods for different cases:
