Mitsubishi Electric 800 Series Installation Manualline page 14

WIRING
2.3.2 Total wiring length
l With general-purpose motor
Connect one or more general-purpose motors within the total wiring length shown in the following table.
Pr. 72 setting
(carrier frequency)
2 (2kHz) or lower
3 (3kHz) or higher
Total wiring length (FR-F846-00052(2.2K) or higher)
When driving a 400 V class motor by the inverter, surge voltages attributable to the wiring constants may occur at the motor
terminals, deteriorating the insulation of the motor. In this case, take one of the following measure.
– Use a "400 V class inverter-driven insulation-enhanced motor" and set frequency in Pr. 72 "PWM frequency selection"
according to wiring length.
50 m or shorter
15 (14.5 kHz) or lower
l With PM motor
Use the following wiring length or shorter when connecting a PM motor.
Pr. 72 setting
(carrier frequency)
5 (2 kHz) or lower
6 to 9 (6 kHz)
10 (10kHz) or higher
Use one PM motor for one inverter. Multiple PM motors cannot be connected to an inverter.
CAUTION
l Especially for long-distance wiring, the inverter may be affected by a charging current caused by stray capacitances of the
wiring, leading to an activation of the overcurrent protection, malfunction of the fast-response current limit operation, or even
to an inverter failure. If the fast-response current limit function malfunctions, disable this function.
(For Pr. 156 "Stall prevention operation selection", refer to the FR-F800 Instruction Manual (Detailed).)
l A surge voltage suppression filter (FFR-DT-xxA-SS1) can be used under V/F control and Advanced magnetic flux vector control.
A sine wave filter (FFR-SI-xxA-SS1) can be used under V/F control. Do not use these filters under PM control.
l For details of Pr. 72 "PWM frequency selection", refer to the FR-F800 Instruction Manual (Detailed).
l Refer to the FR-F800 Instruction Manual (Detailed) to drive a 400 V class motor by an inverter.
8
FR-F846-00023(0.75K)
300 m
200 m
500 m or less
Wiring Length
50 m to 100 m
9 (9 kHz) or lower
FR-F846-00038(1.5K) or lower
100 m
50 m
50 m
FR-F846-00038(1.5K)
500 m
300 m
300 m
300 m
300 m + 300 m = 600 m
longer than 100 m
4 (4 kHz) or lower
FR-F846-00052(2.2K) or higher
100 m
100 m
50 m
FR-F846-00052(2.2K) or higher
500 m
500 m