Mitsubishi Electric FR-A872-E Instruction Manual page 55

 Operation while the 24 V external power is supplied
• Fault records and parameters can be read and parameters can be written (when the parameter write from the operation
panel is enabled) using the operation panel keys.
• The safety stop function is invalid during the 24 V external power supply operation.
• During the 24 V external power supply operation, the monitor items related to inputs to main circuit power supply, such as
the output current and converter output voltage, are invalid.
• The alarms, which have occurred when the main circuit power supply is ON, continue to be output after the power supply
is changed to the 24 V external power supply. Perform the inverter reset or turn OFF then ON the power to reset the faults.
• The output data is retained when "1 or 11" is set in Pr.495 Remote output selection.
NOTE
• Inrush current equal to or higher than the 24 V external power supply specification may flow at power-ON. Confirm that the
power supply and other devices are not affected by the inrush current and the voltage drop caused by it. Depending on the
power supply, the inrush current protection may be activated to disable the power supply. Select the power supply and capacity
carefully.
• When the wiring length between the external power supply and the inverter is long, the voltage often drops. Select the
appropriate wiring size and length to keep the voltage in the rated input voltage range.
• In a serial connection of several inverters, the current increases when it flows through the inverter wiring near the power supply.
The increase of the current causes voltage to drop further. When connecting different inverters to different power supplies, use
the inverters after confirming that the input voltage of each inverter is within the rated input voltage range. Depending on the
power supply, the inrush current protection may be activated to disable the power supply. Select the power supply and capacity
carefully.
• When an external 24 V power supply is used, "E.SAF" or "E.P24" may appear if the power supply start-up time is too long (less
than 1.5 V/s).
• "E.P24" may appear when the 24 V external power supply input voltage is low. Check the external power supply input.
• Do not touch the control circuit terminal block (circuit board) during the 24 V power supply operation (when conducted).
Otherwise you may get an electric shock or burn.
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2. INSTALLATION AND WIRING
2.6 Control circuit