2-3 Wiring Installing an AC Reactor •If the Inverter is connected to a large-capacity power transformer (660 kVA or more) or the phase advance capacitor is in use, a large peak current may flow through the input power circuit, causing the converter unit to break down. •Install an optional AC reactor on the input side of the Inverter. An AC reactor will also improve the power factor of the power input side. 2 Installing a Surge Absorber •Always use a surge absorber or diode when magnetic contactors (MC), electromagnetic relays, solenoid valves, solenoid, and magnetic brakes are used.
Design Connecting a Regenerative Braking Unit When running a load with a large inertia or a vertical axis, regenerative energy will return to the Inverter. If overvoltage in the main circuit is generated during deceleration, this indicates that the regenerative energy exceeds the capacity of the Inverter. In this case, use a regenerative braking unit. •When using a regenerative braking unit, be sure to include a sequence whereby the power supply for the Inverter will be turned off in the event of abnormal overheating. Not doing so may result in fire. For a regenerative braking unit: Use the error contact output (MA, MB).
Molded case circuit-breaker (MCCB) MC Magnetic contactor (MC) Inverter 3G3MX R/L1 (L1) S/L2 (L2) T/L3 (N/L3) Power supply N/- P/+2 +1 MC XB OFF ON N P MC SA MA MB DCL DC reactor P RB R1 R2 MC Regenerative braking unit SA * Terminal symbols for 3G3MX-AE ††† are indicated in parentheses ( ). 2-19 Name Model Specifications Regenerative braking unit 3G3AX-RBU21 3/1-phase 200 V For general use (with built-in resistor) 3G3AX-RBU22 For heavy instantaneous regenerative power (with built-in resistor) 3G3AX-RBU41 3-phase 400 V For general use (with built-in resistor)