Omron RX Series User Manual page 98

2 Design
Connection for Separating Inverter Control Circuit Power Supply
from Main Power Supply
If the inverter protection circuit is activated to shut off the magnetic contactor of the input power supply,
the power to the inverter control circuit is also turned off, and the alarm signal cannot be retained.
If the alarm signal must be retained, use control circuit power supply terminals Ro and To.
Connect control circuit power supply terminals Ro and To with the primary circuit of the magnetic
contactor according to the following procedure.
(Connection method)
Receiving electricity specifications
200-V class:
200 to 240 V (+10%, –15%)
(50/60 Hz ±5%)
(282 to 339 VDC)
400-V class:
380 to 480 V (+10%, –15%)
(50/60 Hz ±5%)
(537 to 678 VDC)
Precautions for Correct Use Precautions for Correct Use
To separate the control circuit power supply (Ro, To) from the main circuit power supply (R, S, T),
observe the following instructions:
• For wiring between terminals Ro and To (terminal screw size: M4), use a cable of 1.25 mm
or more.
• Connect a 3 A fuse to the control circuit power supply cable.
• If the control circuit power supply (Ro, To) is turned on before the main circuit power supply
(R, S, T), ground fault detection at power-on is disabled.
• To use a DC power supply for the control circuit power supply (Ro, To), set the Multi-function
Output Operation Selection (C031 to C036) for the multi-function output terminals (P1 to P5)
and relay output terminals (MA, MB, MC) to 00. If the Multi-function Output Operation
Selection is set to 01, the output signal may chatter when the DC power supply is turned off.
• For the terminals Ro and To, the tightening torque should be as follows.
M4: 1.2 N·m (1.4 N·m max.)
2 - 42
(1) Disconnect the connected wire.
(2) Disconnect the J51 connector.
(3) Connect the control circuit power
cable to the control circuit power
supply terminal block.
High-function General-purpose Inverter 3G3RX-V1 User's Manual (I578-E1)
2