Mitsubishi Electric 800 Series Instruction Manual page 80

Noise
propagation
path
When devices that handle low-level signals and are liable to malfunction due to electromagnetic noises, e.g. instruments,
receivers and sensors, are near the inverter or when the signal cables are run near the inverter, the devices may
malfunction due to by air-propagated electromagnetic noises. The following countermeasures must be taken:
• Install easily affected devices as far away as possible from the inverter.
• Run easily affected signal cables as far away as possible from the inverter and its I/O cables.
(a)(b)(c)
• Do not run the signal cables and power cables (inverter I/O cables) in parallel with each other and do not bundle them.
• Set the EMC filter ON/OFF connector of the inverter to the ON position. (Refer to
• Inserting a line noise filter into the output suppresses the radiated noise from the cables.
• Use shielded cables as signal cables and power cables and run them in individual metal conduits to produce further
effects.
When the signal cables are run in parallel with or bundled with the power cables, magnetic and static induction noises
may be propagated to the signal cables to cause malfunction of the devices and the following countermeasures must be
taken:
• Install easily affected devices as far away as possible from the inverter.
(d)(e)(f)
• Run easily affected signal cables as far away as possible from the inverter and its I/O cables.
• Do not run the signal cables and power cables (inverter I/O cables) in parallel with each other and do not bundle them.
• Use shielded cables as signal cables and power cables and run them in individual metal conduits to produce further
effects.
When the power supplies of the peripheral devices are connected to the power supply of the inverter in the same line,
inverter-generated noises may flow back through the power supply cables to cause malfunction of the devices and the
(g) following countermeasures must be taken:
• Set the EMC filter ON/OFF connector of the inverter to the ON position. (Refer to
• Install the line noise filter (FR-BLF, FR-BSF01) to the power cables (output cables) of the inverter.
When a closed loop circuit is formed by connecting the peripheral device wiring to the inverter, leakage currents may flow
(h) through the earthing (grounding) cable of the inverter to cause the device to malfunction. In that case, disconnecting the
earthing (grounding) cable from the device may stop the malfunction of the device.
Data line filter
Data line filter is effective as an EMI countermeasure. Provide a data line filter for the detector cable, etc.
<Example> Data line filter : ZCAT3035-1330 (by TDK)
: ESD-SR-250 (by NEC TOKIN)
Impedance (ZCAT3035-1330)
Impedance (Ω)
10 to 100 MHz 100 to 500 MHz
80 150
The impedance values above are reference values,
and not guaranteed values.
EMI countermeasure example

Enclosure
Inverter
power
supply
Separate inverter and
power line by more than
30 cm (at least 10 cm)
from sensor circuit.
Control
power
supply
Do not earth (ground) the
enclosure directly.
Do not earth (ground) control cable.
NOTE
• For compliance with the EU EMC Directive, refer to
Electro-magnetic interference (EMI) and leakage currents
Product name
Decrease carrier frequency
FR-
EMC
Inverter
BLF
filter
Use 4-core cable for motor
power cable and use one cable
as earth (ground) cable.
Use a twisted pair shielded cable
Power
supply for
sensor
Do not earth (ground) shield but
connect it to signal common cable.
PRECAUTIONS FOR USE OF THE INVERTER
Countermeasure
39 1
Cable fixing band
mount
34 1
TDK
Lot number
OUTLINE DIMENSION DRAWINGS (ZCAT3035-1330)
Install filter (FR-BLF,
FR-BSF01) on
inverter output side.
M
Motor
Sensor
page 137.
page 80.)
page 80.)
[Unit: mm]
3
79