Wiring Of The Main Circuit - Mitsubishi Electric FR-E520 Instruction Manual

2.2.2

Wiring of the Main Circuit

(1) Wiring instructions
1) It is recommended to use insulation-sleeved crimping terminals for power supply and
motor cables.
2) Application of power to the output terminals (U, V, W) of the inverter will damage the
inverter. Never perform such wiring.
3) After wiring, wire off-cuts must not be left in the inverter.
Wire off-cuts can cause an alarm, failure or malfunction. Always keep the inverter clean.
When drilling mounting holes in a control box etc., be careful so that chips and others
do not enter the inverter.
4) Use thick cables to make the voltage drop 2% or less.
If the wiring distance is long between the inverter and motor, a main circuit cable voltage
drop will cause the motor torque to decrease, especially at the output of a low frequency.
(A selection example for the wiring length of 20m is shown on page 23.)
5) For long distance wiring, the overcurrent protection may be activated improperly or
the devices connected to the output side may misoperate or become faulty under the
influence of a charging current due to the stray capacitance of the wiring.
Therefore, the maximum overall wiring length should be as indicated in the following
table. If the wiring length exceeds the value, it is recommended to set "1" in Pr. 156 to
make the high-response current limit function invalid. (When two or more motors are
connected to the inverter, the total wiring length should be within the indicated value.)
Inverter
Capacity
100V,
Non-low
200V
acoustic
class
noise
400V
mode
class
100V,
Low
200V
acoustic
class
noise
400V
mode
class
Overall wiring length (3.7K or more)
0.1K 0.2K
200 200
—— ——
30 100
—— ——
500m maximum
300m+300m=600m
INSTALLATION AND WIRING
0.4K 0.75K
300 500
200 200
200 300
30 100
300m
300m
20
3.7K or
1.5K 2.2K
500 500
300 500
500 500
200 300
more
500
500
500
500
(Unit: m)