Precautions For Use Of The Inverter - Mitsubishi Electric FR-D720 K Series Instruction Manual

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 contained in the enclosure that contains the inverter or when their signal
cables are run near the inverter, the devices may malfunction due to air-propagated electromagnetic noises. The
following measures must be taken:
(1)(2)(3)  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.
 Do not run the signal cables and power cables (inverter I/O cables) in parallel with each other and do not bundle them.
 Insert common mode chokes into I/O and capacitors between the input lines to suppress cable-radiated noises.
 Use shield 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 which causes the devices to malfunction and the following measures must be
taken:
(4)(5)(6)  Install easily affected devices as far away as possible from the inverter.
 Run easily affected signal cables as far away as possible from the I/O cables of the inverter.
 Do not run the signal cables and power cables (inverter I/O cables) in parallel with each other and do not bundle them.
 Use shield 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 malfunction the devices and the
(7)
following measures must be taken:
 Install the common mode filter (FR-BLF, FR-BSF01) to the power cables (output cable) of the inverter.
When a closed loop circuit is formed by connecting the peripheral device wiring to the inverter, leakage currents may
(8) flow through the earth (ground) cable of the inverter to malfunction the device. In such a case, disconnection of the
earth (ground) cable of the device may cause the device to operate properly.
Data line filter
Data line filter is effective as an EMC measure. Provide a data line filter for the detector cable, etc.
EMC measures
Install common mode filter
on inverter input side.
Inverter
power
supply
Install capacitor type FR-BIF filter
on inverter input side.
Separate inverter and power
line by more than 30cm (at
least 10cm) from sensor circuit.
Control
power
supply
NOTE
 For compliance with the EU EMC Directive, refer to the Instruction Manual (Basic).
FR- BLF
FR- BSF01
Enclosure
FR-
BSF01
FR-
BIF
Power
supply
for sensor
Do not earth (ground)
enclosure directly.
Do not earth (ground) control cable.
EMC and leakage currents
Measures
Install common mode filter
Decrease
carrier frequency
on inverter output side.
FR-
Inverter
BSF01
Use 4-core cable for motor
power cable and use one
cable as earthing cable.
Use a twisted pair shielded cable
Sensor
Do not earth (ground) shield but
connect it to signal common cable.
FR- BLF
FR- BSF01
IM Motor
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