Omron SYSDRIVE MX2 SERIES User Manual page 38

2-2 Wiring
In the following cases, the internal converter module may be damaged:
Do not turn on the power and then turn it off again more than once every 3 minutes. Doing so
may damage the Inverter.
Inverter output terminal (U/T1, V/T2, W/T3)
For connection of the output terminal, use the compatible cable or a cable with a larger
diameter. Otherwise, the output voltage between the Inverter and the motor may drop.
Particularly during low-frequency output, a voltage drop occurs with the cable, resulting in
motor torque reduction.
2
Do not mount a phase advance capacitor or surge absorber, because these devices may
cause the Inverter to trip or cause damage to the capacitor or surge absorber.
If the cable length exceeds 20 m (particularly, with 400 V class), a surge voltage may be
generated at the motor terminal depending on stray capacitance or inductance of the cable,
causing the motor to burn out.
To suppress surge voltage, we offer a special filter (3G3AX-NFxxx). For details, contact our
authorized dealer.
To connect several motors, provide a thermal relay for each.
The RC value of each thermal relay should be 1.1 times larger than the motor rated current.The
relay may trip earlier depending on the cable length.In this case, connect an AC reactor to the
Inverter output.
DC Reactor Connection Terminal (+1, P/+2)
This terminal is used to connect the optional DC reactor.
By factory default, a shorting bar has been connected between terminals +1 and P/+2. Before
connecting the DC reactor, remove this shorting bar.
The length of the DC reactor connection cable should be 5 m or shorter.
If the DC reactor is not being used, do not remove the shorting bar.
If you remove the shorting bar without connecting the DC reactor, no power is supplied to the
Inverter main circuit, disabling operation.
2-11
Imbalance ratio of power supply voltage is 3% or more.
Power supply capacity is ten times or more than the Inverter capacity, and 500 kVA or more.
Rapid change in power supply voltage
Example) When several inverters are connected with a short bus.
When the phase advance capacitor is turned on/off.
SYSDRIVE MX2 Series USER'S MANUAL (3G3MX2-Axxxx)