Omron EasySpeed 3G3JE, User Manual, Page: 34 / 133

Chapter 2
2-12
Design
● 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 switched, an excessive peak current may flow through the input power circuit,
causing the converter unit to break down. To prevent this, install an optional AC reactor on the input
side of the Inverter. This also improves the power factor on the power supply side.
● Installing a Surge Absorber
Always use a surge absorber or diode for the inductive loads near the Inverter. These inductive loads
include magnetic contactors, electromagnetic relays, solenoid valves, solenoid, and magnetic
brakes.
● Connecting a Braking Resistor or a Braking Resistor Unit
When driving a vertical axis or a load with a large inertia, regenerative energy is returned to the
Inverter.
If main circuit overvoltage (E05) is generated during deceleration, the regenerative energy will
exceed the Inverter's capacity. If this occurs, use a Braking Resistor or a Braking Resistor Unit.
• Connect the Braking Resistor as shown in the following diagram.
• When using a Braking Resistor, be sure to install a thermal relay to monitor the resistor tem-
perature.
• Include a sequence to turn OFF the power supply to the Inverter if the Braking Resistor or
Braking Resistor Unit overheats. Not doing so may result in fire.
• Braking Resistor: Use thermal relay output for temperature monitoring.
• Braking Resistor Unit: Use the Unit's fault contact output.
Braking Resistors and Braking Resistor Units for 200 V-class Inverters
Inverter Braking Resistor
(Usage rate: 3% ED)
Braking Resistor Unit
(Usage rate: 10% ED)
Minimum connection
resistance
3G3JE-A2002 3G3IV-PERF150WJ201
(200
Ω
, 150 W)
3G3IV-PLKEB20P7
(200
Ω
, 70 W)
200
Ω
3G3JE-A2004
R/L1
S/L2
T/L3
ON
MC
SA
SA
XB
3G3JE
Inverter
Three-phase
200 to 230 V AC
OFF
B1
(1)
(2)
Braking Resistor/
Braking Resistor Unit
MC
XB
(P)
B2
(B)
Braking Unit thermal trip contacts
or external thermal relay contacts
MCCB MC