Mitsubishi Electric 800 Series, Instruction Manual, Page: 644 / 727

Causes and corrective actions
PROTECTIVE FUNCTIONS
643
6 5
Abbreviation E.P24
FR-LU08 24 VDC power fault
FR-PU07 E.P24
Name
24 VDC power fault
Description
When the 24 VDC power output from the PC terminal is shorted, this function shuts off the power output.
At this time, all external contact inputs switch OFF. The inverter cannot be reset by entering the RES signal.
To reset it, use the operation panel, or switch power OFF, then ON again.
Check point
• Check for a short circuit in the PC terminal output.
• Check that the 24 V external power supply voltage is correct.
Corrective action
• Repair the short-circuited portion.
• Supply the power at 24 V. (If the power at insufficient voltage is supplied to the 24V input circuit for a long
time, the inverter internal circuit may heat up. Input power at correct voltage although it will not damage the
inverter.)
Abbreviation E.CDO
FR-LU08
FR-PU07
OC detect level
Name
Abnormal output current detection
Description
The inverter trips if the output current exceeds the Pr.150 Output current detection level setting.
This functions is available when Pr.167 Output current detection operation selection is set to "1". When
the initial value ( Pr.167 = "0") is set, this protective function is not available.
Check point
Check the settings of Pr.150, Pr.151 Output current detection signal delay time, Pr.166 Output current
detection signal retention time, and Pr.167 . (Refer to page 382 .)
Abbreviation E.IOH
FR-LU08
FR-PU07
Inrush overheat
Name
Inrush current limit circuit fault (Standard models only)
Description
The inverter trips when the resistor of the inrush current limit circuit is overheated. The inrush current limit
circuit failure
Check point
• Check that frequent power ON/OFF is not repeated.
• Check if the input side fuse (5A) in the power supply circuit of the inrush current limit circuit contactor (FR-
A860-02890 or higher) is blown.
• Check that the power supply circuit of inrush current limit circuit contactor is not damaged.
Corrective action
Configure a circuit where frequent power ON/OFF is not repeated.
If the situation does not improve after taking the above measure, please contact your sales representative.
Abbreviation E.SER
FR-LU08
FR-PU07
VFD Comm error
Name
Communication fault (inverter)
Description
The inverter trips when communication error occurs consecutively for the permissible number of retries or
more when
Pr.335 RS-485 communication retry count

"9999" during RS-485 communication from the
RS-485 terminals. The inverter also trips if communication is broken for the period of time set in Pr.336 RS-
485 communication check time interval .
Check point
Check the RS-485 terminal wiring.
Corrective action
Perform wiring of the RS-485 terminals properly.
Abbreviation E.AIE
FR-LU08
FR-PU07
Analog in error
Name
Analog input fault
Description
The inverter trips when a 30 mA or higher current or a 7.5 V or higher voltage is input to terminal 2 while the
current input is selected by
Pr.73 Analog input selection , or to terminal 4 while the current input is selected
by Pr.267 Terminal 4 input selection .
Check point
Check the Pr.73 , Pr.267 , and the voltage/current input switch settings. (Refer to page 393 )
Corrective action
Either give a current less than 30 mA, or set Pr.73 , Pr.267 , and the voltage/current input switch to the voltage
input and input a voltage.
Abbreviation E.USB
FR-LU08
FR-PU07
USB comm error
Name
USB communication fault
Description
The inverter trips when the communication is cut off for the time set in Pr.548 USB communication check
time interval .
Check point • Check that the USB communication cable is connected securely.
Corrective action
• Check the Pr.548 setting.
• Connect the USB communication cable securely.
• Increase the
Pr.548 setting or set "9999." (Refer to page 584 .)