HV100 Series High Performance Current Vector Inverter
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electrostatic induction. Thereby causing misoperation of the equipment. According to several different interference
situations, refer to the following methods to solve them:
1) The instruments, receivers and sensors used for measurement have weak signals. If they are close to the inverter or
in the same control cabinet, they are prone to interference and misoperation. The following solutions are recommended: try
to stay away from interference sources; Do not arrange the signal line and the power line in parallel, especially do not
bundle them together in parallel; Shielding wires shall be used for signal lines and power lines, and the grounding shall be
good; Add ferrite magnetic ring on the output side of the inverter (choose the suppression frequency in the range of 30 ~
1000 MHz) and wind it for 2 ~ 3 turns in the same direction. For the bad situation, you can choose to install EMC output
filter;
2) When the interfered equipment and the inverter use the same power supply, it will cause conducted interference. If
the interference cannot be eliminated by the above methods, an EMC filter should be installed between the inverter and the
power supply (refer to 7.3.6 for selection operation);
3) The peripheral equipment is grounded separately, which can eliminate the interference caused by leakage current
in the grounding line of the inverter.
8.3.5 Leakage current and treatment:
There are two forms of leakage current when using inverter: one is leakage current to ground; The other is the leakage
current between lines.
1) factors affecting the floor drain current and solutions:
There is distributed capacitance between the conductor and the ground, and the greater the distributed capacitance,
the greater the leakage current; Effectively reduce the distance between inverter and motor to reduce distributed
capacitance. The larger the carrier frequency, the greater the leakage current. The carrier frequency can be lowered to
reduce leakage current. However, reducing the carrier frequency will lead to an increase in motor noise. Please note that
installing reactors is also an effective way to solve leakage current.
The leakage current will increase with the increase of loop current, so when the motor power is high, the corresponding
leakage current will be large.
2) Factors causing leakage current between lines and solutions:
There is distributed capacitance between the output wires of the inverter. If the current passing through the wires
contains higher harmonics, it may cause resonance and leakage current. At this time, if the thermal relay is used, it may
cause misoperation.
The solution is to reduce the carrier frequency or install an output reactor. When using the inverter, it is suggested that
no thermal relay should be installed between the inverter and the motor, and the electronic overcurrent protection function
of the inverter should be used.
8.3.6 Precautions for installing EMC input filter at power input end:
1)
Note: Please use the filter strictly according to the rated value; As the filter belongs of Class I electrical
appliances; the metal outer shell for the filter should have good contact with the metal for the installation cabinet of large
area; and it is required of have good conductivity continuity; otherwise; there will be the danger for electrical contact and
seriously affect the EMC effect.
2) Through EMC test, it is found that the filter ground must be connected to the same common ground as the PE end of
the inverter, otherwise the EMC effect will be seriously affected.
3) Install the filter as close as possible to the power input of the inverter.
