Installation and wiring
● With PM motor
Use the following wiring length or shorter when connecting a PM motor.
Use one PM motor for one inverter. Multiple PM motors cannot be connected to an inverter.
Especially for long-distance wiring or wiring with shielded cables, the inverter may be affected by
a charging current caused by stray capacitances of the wiring, leading to an activation of the over-
current protection, malfunction of the fast-response current limit operation, or even to an inverter
failure. It may also cause a malfunction or fault of the equipment connected ON the inverter out-
put side. Stray capacitances of the wiring differ by the installation condition, use the total wiring
length in the table above as reference values. If the fast-response current limit function malfunc-
tions, disable this function. (Refer to Pr. 156 "Stall prevention operation selection" on page 5-180.)
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.
For the details of Pr. 72 "PWM frequency selection", refer to page 5-88.
For the details of the surge voltage suppression filter (FR-ASF-H/FR-BMF-H) and the sine wave filter
(MT-BSL/BSC), refer to the Instruction Manual of each option.
Refer to page 3-19 to drive a 400V class motor by an inverter.
Pr. 72 setting
0 (2 kHz) to 15 (14 kHz)
≤ 5 (2 kHz)
6 to 9 (6 kHz)
≥ 10 (10 kHz)
Total wiring length (with PM motor)
FR-F820-00077(1.5K) or lower,
FR-F840-00038(1.5K) or lower
Main circuit terminals
FR-F820-00105(2.2K) or higher,
FR-F840-00052(2.2K) or higher
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