Omron MX2 Series User Manual

2 Design
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Multi-function Compact Inverter 3G3MX2-EV2 User’s Manual (I666-E1)
When driving a load with a large inertia or a vertical axis, regenerated energy is fed back to the inverter
when it is decelerating or generating downward movement.
If the amount of regenerative energy exceeds the amount allowable for the inverter, an overvoltage is
detected. Use braking resistors or regenerative braking units to prevent this.
⚫ Using built-in regenerative braking circuit
All models of the 3G3MX2-EV2 Series Inverter have built-in regenerative braking circuit.
To improve the braking capacity, connect the optional external braking resistor to these terminals (P/+,
RB).
• Be sure to install a circuit that detects overheating of the braking resistor via alarm contacts
(thermal relay output terminals) and shuts off the input power supply of the inverter.
• Do not connect a resistor whose resistance is lower than the minimum connection resistance
value specified in the standard specifications table. Doing so may result in damage to the
regenerative braking circuit.
• When using the Braking Resistor make sure that both average and peak power of both
inverter and resistor are respected, as well as isolation capability and rating of the resistor
should match the inverter voltage class
• Wiring diagram
Braking resistor
⚫ Using regenerative braking unit (Optional)
If a large braking torque is required and the built-in regenerative braking circuit cannot allow it, use
the Regenerative Braking Unit (optional).
In this case, connect the terminals (P/+2, N/−) of the regenerative braking unit to the inverter’s termi-
nals (P, N).
• Be sure to install a circuit that detects overheating of the regenerative braking unit(s) and
braking resistor(s) via alarm contacts (thermal relay output terminals) and shuts off the input
power supply of the inverter.
• Do not connect a resistor whose resistance is lower than the connection resistance value
specified in the specifications table for that regenerative braking unit. Doing so may result in
damage to the regenerative braking unit.
• When using the Braking Resistor with a 400-V class Regenerative Braking Unit, be sure to
connect two braking resistors of the same model in series. Using the Regenerative Braking
Unit with only one braking resistor connected may cause burnout of the braking resistor.
External Braking Resistor Connection Terminal (P/+, RB)/
Regenerative Braking Unit Connection Terminal (P/+, N/–)
Precautions for Safe Use
+1 P/+ N/− RB
Precautions for Safe Use

Omron MX2 Series Specifications

General

Cooling Method	Fan cooling
Output Frequency Range	0.1 to 400 Hz
Control Method	V/f control, Sensorless vector control
Protection Functions	Overcurrent, overvoltage, undervoltage, overload, overheating, short circuit
Communication Options	Modbus RTU
Overload Capacity	150% for 60 seconds
Braking Unit	Built-in
Ambient Operating Temperature	-10°C to +50°C
Enclosure	IP20
Storage Temperature	-20°C to +65°C
Humidity	5 to 95% RH (non-condensing)
Altitude	Up to 1000m
Power Supply Voltage	200-240V AC
Input Voltage	3-phase 200-240V AC