INVT CHV160A Series - Page 40

C.TY TNHH TỰ ĐỘNG HÓA VIỆT TRUNG 02413.281.181-
0989.984.666
Website:www.viet-trung.com.vn Đ/c:194-Nguyễn Trãi-Võ Cường-
TP.Bắc Ninh
power cables to make the equipment malfunction. Therefore when wiring, signal cables
and power cables should be arranged in different area. It is strictly prohibitive to arrange
them in parallel or interlacement at a close distance (less than 20cm) or tie them together.
If the signal wires have to cross the power cables, they should be arranged in 90 angles.
Power input and output cables should not either be arranged in interlacement or tied
together, especially when installed the EMC filter. Otherwise the distributed capacitances
of its input and output power cable can be coupling each other to make the EMC filter out
of function.
4.6.3.3 Ground
Inverter must be ground safely when in operation. Grounding enjoys priority in all EMC
methods because it does not only ensure the safety of equipment and persons, but also is
the simplest, most effective and lowest cost solution for EMC problems.
Grounding has three categories: special pole grounding, common pole grounding and
series-wound grounding. Different control system should use special pole grounding, and
different devices in the same control system should use common pole grounding, and
different devices connected by same power cable should use series-wound grounding.
4.6.3.2 Leakage current
Leakage current includes line-to-line leakage current and over-ground leakage current.
Its value depends on distributed capacitances and carrier frequency of inverter. The
over-ground leakage current, which is the current passing through the common ground
wire, can not only flow into inverter system but also other devices. It also can make
leakage current circuit breaker, relay or other devices malfunction. The value of
line-to-line leakage current, which means the leakage current passing through distributed
capacitors of input output wire, depends on the carrier frequency of inverter, the length
and section areas of motor cables. The higher carrier frequency of inverter, the longer of
the motor cable and/or the bigger cable section area, the larger leakage current will
24