MITSUBISHI ELECTRIC FR-S520 - Manual (Page 28)

19
1
Noise reduction examples
Inverter
FR-
BIF
Sensor
Use 4-core cable for motor
power cable and use one
cable as earth cable.
Power
supply
for sensor
Use twisted pair shielded cable.
Inverter
power supply
Control
power supply
Do not earth shield but connect
it to signal common cable.
Separate inverter and power
line more than 30cm (3.94inches)
(at least 10cm (11.81inches))
from sensor circuit.
Install filter FR-BIF
on inverter's input side.
Control
box
Reduce carrier
frequency.
Motor IM
FR-
BLF
FR-
BLF
FR-BLF
FR-BSF01
Do not earth control
box directly.
Do not earth
control cable.
FR-BLF
FR-BSF01
Install filter
on inverter's input side.
Install filter
on inverter's output side.
1
.5.8 Grounding precautions
Leakage currents flow in the inverter. To prevent an electric shock, the inverter and
motor must be grounded.
Use the dedicated ground terminal to ground the inverter. (Do not use the screw in
the casing, chassis, etc.)
Use a tinned* crimping terminal to connect the earth cable. When tightening the
screw, be careful not to break the threads.
*Plating should not include zinc.
Use the thickest possible ground cable. Use the cable whose size is equal to or
greater than that indicated in the following table, and minimize the cable length.
The grounding point should be as near as possible to the inverter.
(Unit: mm
2
)
Ground Cable Size
Motor Capacity
200V, 100V class 400V class
2.2kW (3HP) or less 2 (2.5) 2 (2.5)
3.7kW (5HP) 3.5 (4) 2 (4)
For use as a product compliant with the Low Voltage Directive, use PVC cable
whose size is indicated within parentheses.
Ground the motor on the inverter side using one cable of the 4-core cable.