Mitsubishi Electric FR-F500 Series Instruction Manual page 46

Noise Path
When devices that handle low-level signals and are liable to malfunction due to 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 be malfunctioned by air-propagated noises. The following measures
must be taken:
(1) Install easily affected devices as far away as possible from the inverter.
1) 2) 3) (2) Run easily affected signal cables as far away as possible from the inverter.
(3) Do not run the signal cables and power cables (inverter I/O cables) in parallel with each other and do not
bundle them.
(4) Inset line noise filters into I/O and radio noise filters into input side to suppress cable-radiated noises.
(5) Use shielded cables for signal cables and power cables and run them in individual metal conduits to reduce
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 malfunction the devices and the following measures must be
taken:
(1) Install easily affected devices as far away as possible from the inverter.
4) 5) 6) (2) Run easily affected signal cables as far away as possible form the inverter.
(3) Do not run the signal cables and power cables (inverter I/O cables) in parallel with each other and do not
bundle them.
(4) Use shielded cables for signal cables and power cables and run them in individual metal conduits to reduce
further effects.
When the power supplies of the peripheral devices are connected to the power supply of the inverter within the
same line, inverter-generated noise may flow back through the power supply cables to misoperate the devices
7) and the following measures must be taken:
(1) Install the radio noise filter (FR-BIF) to the power cables (input cables) of the inverter.
(2) Install the line noise filter (FR-BLF, FR-BSF01) to the power cables (I/O cables) of the inverter.
When a closed loop circuit is formed by connecting the peripheral device wiring to the inverter, leakage current
8) may flow through the earth (ground) cable of the inverter to affect 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
Noise entry can be prevented by providing a data line filter for the detector cable etc.
7)
2)
1)
3)
Instrument Receiver
Motor
INSTALLATION AND WIRING
5)
Telephone
7)
2)
Sensor power supply
In-
verter
6)
4)
8)
Sensor
3)
IM
Measures
35