Chapter 2 Wiring of V 810
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also cause a fault in the power circuit, relays or other devices. The value of the leakage
current in the line, which means the leakage current passing through the distributed
capacities of the input and output conductor, depends on the carrier frequency of the
inverter, on the length and cross section of the motor cables. The higher the carrier
frequency of the inverter, the longer the motor cable and / or the larger the cross-section
of the cables, the higher the leakage current.
Countermeasures:
Decreasing the carrier frequency can effectively reduce the leakage current. In the case of
a motor cable that is relatively long (longer than 50 meters), an AC or sine wave reactor
must be installed on the output side, and when the line is even longer, one reactor must
be mounted at a certain distance.
7./ EMC filter
The EMC filter has a great influence on electromagnetic interference, so it is more
advantageous for the customer to install it.
From the point of view of the inverter, the installation of a noise filter has the following
options:
• Noise filter installed on the input side of the inverter;
• Install a noise filter for other devices using an isolation transformer or voltage filter.
Example of interference suppression on the output side of the inverter using a ferrite ring:
NOTES wire check:
(1) Place control signal cables and mains and other power lines separately.
(2) To prevent interference caused by interference, use a twisted pair or two-wire
shielded cable with a cross section of 0.5 to 2 mm2.
(3) Make sure that the terminals used are suitable in terms of voltage and maximum
current load.
(4) Use the correct earth terminal E, the earth resistance must be less than ˂10 ohms, STN
EN 62305-3. Use the prescribed cross-section of the earth conductor. The cross-sections of
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