Mitsubishi FR-F720-00046-NA Instruction Manual page 34

Main circuit terminal specifications
(3) Total wiring length
The overall wiring length for connection of a single motor or multiple motors should be within the value in the table below.
Pr. 72 PWM frequency selection Setting
(carrier frequency)
2 (2kHz) or less
3 to 15 (3kHz to 14.5kHz) *
* For the FR-F720-03160 (FR-F740-01800) or higher, the setting range of Pr. 72 PWM frequency selection is "0 to 6".
When driving a 400V class motor by the inverter, surge voltages attributable to the wiring constants may occur at the
motor terminals, deteriorating the insulation of the motor.
Take the following measures 1) or 2) in this case. (Refer to page 52)
1) Use a "400V class inverter-driven insulation-enhanced motor" and set frequency in Pr. 72 PWM frequency selection
according to wiring length
Pr. 72 PWM frequency selection Setting
(carrier frequency)
2) Connect the surge voltage suppression filter (FR-ASF-H/FR-BMF-H) to the FR-F720-02330 (FR-F740-01160) or
lower and the sine wave filter (MT-BSL/BSC) to the FR-F720-03160 (FR-F740-01800) or higher on the inverter
output side.
CAUTION
· Especially for long-distance wiring, the inverter may be affected by a charging current caused by the stray capacitances of the
wiring, leading to a malfunction of the overcurrent protective function or fast response current limit function or a malfunction or fault
of the equipment connected on the inverter output side. If fast-response current limit function malfunctions, disable this function.
(For Pr.156 Stall prevention operation selection, refer to page 81.)
· For details of Pr. 72 PWM frequency selection , refer to page 171. (When using an optional sine wave filter (MT-BSL/BSC) for the
FR-F720-03160 (FR-F740-01800) or higher, set "25" in Pr.72 (2.5kHz)).
· For explanation of surge voltage suppression filter (FR-ASF-H/FR-BMF-H) and sine wave filter (MT-BSL/BSC), refer to the
manual of each option.
(4) Cable size of the control circuit power supply (terminal R1/L11, S1/L21)
· Terminal Screw Size: M4
2
· Cable size: 0.75mm
· Tightening torque: 1.5N·m
24
Total wiring length (FR-F720-00105 (FR-F740-00052) or higher)
300m (984.25feet) + 300m (984.25feet)
= 600m (1968.50feet)
50m (164.04feet) or
14.5kHz or less
2
to 2mm
FR-F720-00046 FR-F720-00077
FR-F740-00023 FR-F740-00038
300m
(984.25 feet) (1640.42 feet)
200m
(656.19 feet) (984.25 feet)
500m
(1640.42feet)
or less
300m
(984.25feet)
300m
(984.25feet)
Wiring Length
50m (164.04feet) to
less 100m (328.08feet)
9kHz or less
FR-F720-00105 or higher
FR-F740-00052 or higher
500m 500m
(1640.42 feet)
300m 500m
(1640.42 feet)
exceeding 100m
(328.08feet)
4kHz or less