Instruction manual

Table Of Contents
INSTALLATION AND WIRING
31
2.3.3 Inverter-driven 575V class motor
In the PWM type inverter, a surge voltage attributable to wiring constants is generated at the motor terminals.
Especially for a 575V class motor, the surge voltage may deteriorate the insulation.
100%
0
200
150
Voltage at a motor terminal (%)
10 20 30 40 50 60 70 80 90 100
Motor wiring length (m)
Surge voltage at a motor terminal by motor wiring length (reference)
When the 575V class motor is driven by the inverter, consider the following measures:
Measures
(1) Inverter duty motor
Select an inverter duty motor. Many motor manufacturers sell motors with insulation systems designed
to withstand the stress imposed by PWM inverters.
(2) AC reactor
For added protection, install an AC reactor on the inverter output.