FujiFilm FRENIC5000G11S Series, Техническая информация

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Chapter 8
Appendix 1. Advantageous Use of Inverters (with regard to Electrical Noise)
8-6
(2) Control panel
The control panel containing the inverter is generally made of metal, and this metal box can shield noise radiated from the
inverter itself.
Further, when installing other electronic devices such as a programmable logic controller in the same control panel, attention
should be paid to the arrangement of each device. When necessary, a noise prevention measure should be implemented, such
as installing a shielding plate between the inverter and peripheral devices.
(3) Anti-noise devices
To reduce the noise propagated through the electrical circuits and the noise radiated from the main circuit wiring to the air, a
line filter and power supply transformer are utilized (refer to Fig 10).
Among line filters, there are the simple type filters, such as a capacitive filter connected in parallel to the power supply line and
an inductive filter connected in series to the power supply line, as well as orthodox filters (LC filters). These filters are used
according to the targeted effect for reducing noise. In power supply transformers, there are common insulated transformers,
shielded transformers, noise-cut transformers, etc. These transformers have different effectiveness in blocking noise propaga-
tion.
Fig. 8 Grounding of metal conduit pipe Fig. 9 Treatment of braided wire of shielded wire
Table 1 Noise prevention methods
Goal of noise prevention measure Conduction route
Noise prevention method
Make it more Cutoff noise Confine Reduce Conduction Induction Radiation
difficult to conduction noise noise level noise noise noise
receive noise
Separate main circuit and control circuit
Minimum wiring distance
Avoid parallel and bundled wiring
Use appropriate grounding
Use shielded wire and twisted shielded wire
Use shielded cable in main circuit
Use metal conduit pipe
Control panel Appropriate arrangement of devices in panel
Metal control panel
Anti-noise device Line filter
Insulation transformer
Use passing capacitor
Use ferrite core for control circuit
Line filter
Others Separate power supply systems
Lower the carrier frequency
Wiring and
installation
Treatment on the
noise receiving
side
Metal conduit pipe Metal conduit pipe
Inverter M
Inverter
0V
(Common)
Inverter
0V
(Common)
Connection
terminals
Chapter8-1(P1˜10).p65
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