Mitsubishi Electronics FR-V540-1.5K to 55K Marine Battery User Manual


 
18
Others
z Data line filters
Noise entry can be prevented by providing a data line filter for the detector cable etc.
z Example of noise reduction techniques
Noise Propagation
Path
Measures
1), 2), 3)
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.
(2) Run easily affected signal cables as far away as possible from the inverter and its I/O cables.
(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) Insert line noise filters into I/O and radio noise filters into input to suppress cable-radiated noises.
(5) Use shielded cables as signal cables and power cables and run them in individual metal conduits
to produce further effects.
4), 5), 6)
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.
(2) Run easily affected signal cables as far away as possible from the I/O cables of 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 as signal cables and power cables and run them in individual metal conduits
to produce further effects.
7)
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 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.
8)
When a closed loop circuit is formed by connecting the peripheral device wiring to the inverter, leakage
currents may 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.
IM
Inverter
power supply
Control
power supply
Control box
Reduce carrier
frequency.
Inverter
Power supply
for sensor
Motor
Use twisted pair shield cable.
Sensor
Separate inverter and power
line by more than 30cm
(at least 10cm) from sensor circuit.
Do not earth (ground)
control cable.
Do not earth (ground)
control box directly.
Do not earth (ground) shield but connect
it to common cable of signal.
Use 4-core cable as motor
power cable and use one wire
as earth (ground) wire.
FR-
BIF
FR-
BLF
FR-
BLF
Install filter
(FR-BLF, FR-BSF01)
on inverter input side.
Install FR-BIF filter
on inverter input side.
Install filter
(FR-BLF, FR-BSF01)
on inverter output side.