Chapter 2 Wiring of V 810
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2./ Electrical installation
Power supply: the power supply should be separated by an electrical transformer. The
cable should consist of 5 conductors, three of which are phase conductors, one is the
neutral conductor and one of them is ground. It is strictly forbidden to use the same
conductor as the neutral and at the same time the earth conductor.
3./ Equipment categorization
In one distribution box, there are various electrical devices, such as inverter, filter, PLC,
etc., that have a different ability to radiate and resist electromagnetic interference. It is
therefore necessary to classify these devices in a category with a high degree of radiation
and interference sensitivity. The same types of equipment should be located in the same
area. The distance between devices of different categories should be greater than 20 cm.
4./ Arrangement of conductors inside the switchboard
In one switchboard there are signal cables (low current) and power cables (high current).
In terms of the inverter, the power cables are divided into input and output cable. Signal
cables can be easily disturbed by power cables. Therefore, cables, both signal and power,
should be laid separately. It is strictly forbidden to arrange them in parallel or to cross
them at a distance of less than 20 cm or to tie them. If the signal wires must pass through
the power cables, they should cross at a 90° angle. Input and output cables should not be
arranged next to each other or connected to each other, especially when installing an EMC
filter. Otherwise, the distributed capacities of the input and output power cables are
interconnected, causing the EMC filter to malfunction.
5./ Grounding
The inverter must be safely grounded during operation. Grounding takes precedence in all
EMC methods because it not only ensures the safety of equipment and people, but is also
the simplest, most efficient and cheapest solution for solving EMC problems. Grounding
has three categories: special grounding, common grounding, and series grounding.
Different control systems should use a separate ground, different devices in the same
control system should use a common ground, and different devices connected to the
same power cord should use a serial ground.
6./ Leakage current
The leakage current includes the leakage current between the conductors and the leakage
current to ground. Its value depends on the distributed capacity and the carrier inverter.
The earth leakage current, which is the current flowing through the common ground
conductor, can flow not only into the inverter system but also into other devices. It can
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