Inverters are power supply devices that control the frequency (Hz) of three-phase induction motors to vary speed continuously. Speed can be controlled by changing frequency because the speed of rotation of induction motors is determined by the number of poles and the frequency. For example, a four-pole induction motor will rotate at a constant speed of 1500 min-1 at a power frequency of 50 Hz or 1800
min-1 at 60 Hz. Here, the speed of the motor can be freely varied, regardless of power
frequency, by installing an inverter between the power supply and the motor.
These are compact inverters that have functions optimal for a wide array of low-capacity needs.Their operation and wiring are simple, and frequency can be easily set with a knob. Their power supply is 3-phase 200 V series. The line-up includes seven sizes from 0.1 kW to 3.7 kW for the standard applied motor. Ease of maintenance is excellent and the inverters have many protection features helpful with peripherals. They also comply with non-Japanese standards, such as EU Directives (the CE mark), UL standards, and Canadian standards (cUL standards).