Omron SYSDRIVE 3G3RV, Руководство пользователя

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Wiring Main Circuit Terminals
2-
25
Countermeasures Against Radio Interference
Radio
noise is generated from the Inverter as well as from the input and output lines. To reduce radio noise,
install
noise filters on both input and output sides, and also install the Inverter in a totally enclosed steel box.
The
cable between the Inverter and the motor should be as short as possible.
Fig 2.14 Countermeasures Against Radio Interference
Cable Length between Inverter and Motor
If
the cable between the Inverter and the motor is long, the high-frequency leakage current will increase, caus-
ing
the Inverter output current to increase as well. This may affect peripheral devices. To prevent this, adjust
the
carrier frequency (set in C6-01, C6-02) as shown in Table 2.11. (For details, refer to Chapter 5 Parame-
ters.)
Restriction on Using Single-phase Motors
Single-phase
motors are not suited for variable-speed operation using the Inverter. There are two methods
used
to determine the operating direction for a single-phase motor upon startup: Capacitor startup and split-
phase
startup. With the capacitor startup method, there is a possibility that the steep charge and discharge of
the
Inverter output will damage the capacitor. Likewise, with the split-phase startup method, there is a possi-
bility
of damaging the starting coil because there is no centrifugal switch operation.
n
Ground Wiring
Observe
the following precautions when wiring the ground line.
•
Always
use the ground terminal of the 200-V Inverter with a ground resistance of less than 100 Ω and that
of
the 400-V Inverter with a ground resistance of less than 10 Ω
.
• Do
not share the ground wire with other devices, such as welding machines or power tools.
• Always
use a ground wire that complies with technical standards on electrical equipment and minimize the
length
of the ground wire.
Leakage
current flows through the Inverter. Therefore, if the distance between the ground electrode and the
ground
terminal is too long, potential on the ground terminal of the Inverter will become unstable.
•
When
using more than one Inverter, be careful not to loop the ground wire.
Fig 2.15 Ground Wiring
Table 2.11 Cable Length between Inverter and Motor
Cable length 50 m max. 100 m max. More than 100 m
Carrier
frequency
15
kHz max.
10
kHz max.
5
kHz max.
IM
MCCB
Power
supply
Inverter
Noise
filter
Metal pipe
Noise
filter
Steel box
OK NO