Connect one or more general-purpose motors within the total wiring length shown in the following table. (The wiring length should be 100 m or less under

vector control.)

Pr.72 setting

(carrier frequency)

2 (2 kHz) or lower

300 m

3 (3 kHz) or higher

200 m

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 Pr. 72 PWM frequency selection according to the wiring length.

Wiring length shorter than 50 m

15 (14.5 kHz) or less

• Connect the surge voltage suppression filter (FR-ASF-H, FR-BMF-H) to the output side of the FR-A840-01800(55K) or lower and the sine wave filter (MT-

BSL, MT-BSC) to the output side of the FR-A840-02160(75K) or higher.

 With PM motor

Use the wiring length of 100 m or shorter when connecting a PM motor.

Use one PM motor for one inverter. Multiple PM motors cannot be connected to an inverter.

When the wiring length exceeds 50 m for a 400 V class motor driven by an inverter under PM sensorless vector control, set "9" (6 kHz) or less in Pr.72 PWM

frequency selection.

NOTE

• 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.

(Pr.156 Stall prevention operation selection Refer to Chapter 5 of the Instruction Manual (Detailed).)

• For details of Pr.72 PWM frequency selection, refer to Chapter 5 of the Instruction Manual (Detailed).

• A surge voltage suppression filter (FR-ASF-H/FR-BMF-H) can be used under V/F control and Advanced magnetic flux vector control.

A sine wave filter (MT-BSL/BSC) can be used under V/F control. Do not use the filters under different control methods.

• Refer to Chapter 3 in the Instruction Manual (Detailed) to drive a 400 V class motor by an inverter.

• The carrier frequency is limited with a PM motor. (Refer to Chapter 5 of the Instruction Manual (Detailed).)

 Cable size for the control circuit power supply (terminals R1/L11 and S1/L21)

• Terminal screw size: M4

• Cable gauge: 0.75 mm

to 2 mm

• Tightening torque: 1.5 N