HNC Electric HV480 Series, Руководство пользователя

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355 500 660
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500 760 1050
Precautions for installation:
1) The grounding wire of frequency inverter and other electrical products shall be well grounded; the
filter must be connected to the same common ground as the PE end of the frequency inverter, otherwise it
will seriously affect the EMC effect. The input filter is installed as close as possible to the power input of the
frequency inverter.
Shield cables for the control signal lines and lead wires of the test lines of the frequency inverter and
reliably ground the shield layer.
2 ) The power input and output lines and weak current signal lines ( e.g. control lines ) of the frequency
inverter should not be arranged in parallel as far as possible, and should be arranged vertically when
conditions permit.
3) It is recommended to use shielded cable or steel pipe to shield the power line for the output power
line of the frequency inverter, and the shielding layer should be reliably grounded.
4) It is recommended to use twisted pair shielding control lines for the leads of the interfered equipment
and reliably ground the shielding layer;
5) If peripheral equipment is grounded separately, interference caused by leakage current of frequency
inverter grounding line can be eliminated.
8.2.8 Leakage protector
There are two forms of leakage current when using frequency inverter: one is leakage current between wires,
the other is leakage current to ground. The former leakage current has been explained in the section of reactor. This
section only discusses leakage current to floor drain.
There may be insulation and leakage for other reasons in the frequency inverter and its accessories and related
circuits. Moreover, because there are distributed capacitors in the frequency inverter, the motor and its wiring with
the earth, the larger the distributed capacitor is, the larger the leakage current is. However, this series frequency
inverter is designed with low noise, so the carrier frequency is higher, the higher the carrier frequency is, the greater
the leakage current is. The leakage current will increase as the return current increases, so when the motor power
is high, the corresponding leakage current will be high. Validly reduce the distance between the frequency inverter
and the motor to reduce the distributed capacitance. The carrier frequency can be lowered to reduce leakage current,
but lowering the carrier frequency will result in increased motor noise. Installing reactors is also a valid way to solve
leakage current. However, there must be a current to the floor drain. Installing a leakage protector is also a valid
method to protect the frequency inverter.
The leakage protector shall be installed between the incoming line end of the frequency inverter and the mccb of
the air switch. The criterion for selecting its specifications is that the operating current of the leakage protector shall
not be less than ten times that of the line when the frequency inverter is not used under the power frequency power
supply.
8.2.9 Capacitance box
This peripheral device is specially used for occasions where the power failure time is long and the motor needs
continuous operation. Although this series frequency inverter has the advanced function of instant stop, the capacitor
box can still be used under the special circumstances of specific requirements (the instantaneous power failure of the
power supply is greater than 20 ms). If necessary, specify the specific requirements when ordering.
Since the installation of this external device will affect some parameters in the machine, so you do not want
users to install it themselves. Please contact our Company.