Instruction manual

INSTALLATION AND WIRING
38
Noise Path Measures
1), 2), 3)
When devices which handle low-level signals and are susceptible to
misoperation due to noise (such as instruments, receivers and sensors)
are installed near the inverter and their signal cables are contained in the
same panel as the inverter or are run near the inverter, the devices may
be misoperated by air-propagated noise 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
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) Insert line noise filters onto I/O and radio noise filters into inputs to
suppress cable-radiated noises.
(5) Use shielded cables for signal cables and power cables and run them
in individual metal conduits to further reduce 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 causing misoperation of 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
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 further reduce effects.
7)
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 causing misoperation of
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 current may flow through the ground cable
of the inverter causing misoperation of the device. In such a case,
disconnection of the ground cable of the device may cause the device to
operate properly.
2