Mitsubishi FR inverters are among the most commonly used converters in industrial automation. Valued for their reliability and extensive control functions, they can operate in demanding conditions for many years. However, when they detect an anomaly, they display an appropriate error code that helps quickly understand what is happening in the system. Below you will find a practical discussion of selected messages from the ER series, along with possible causes and ways to fix the fault.
Error Er1 - parameter write error
Er1 - possible cause of Mitsubishi FR inverter error
The inverter reports Er1 when an attempt was made to change a parameter, even though the write function was previously locked in the settings. The problem also occurs when frequency values overlap or there is a conflict in the five-point V/F characteristic. Sometimes the error results from a lack of communication between the PU panel and the converter.
Er1 - how to fix Mitsubishi FR inverter error
Check the parameter responsible for write protection and verify the jump frequency settings. It is also advisable to assess the correctness of the V/F characteristic and ensure that the connection with the PU panel is working properly. If the error still occurs, disconnecting the panel and restarting the inverter helps confirm whether the problem is related to communication.
If the problem persists, contact a professional service: inverter repair.
Error Er2 - write error during converter operation
Er2 - possible cause of Mitsubishi FR inverter error
The inverter registers Er2 when the user attempts to save a parameter while the device is running. If the write lock parameter is set to a value other than 2, saving is only possible in selected modes. Therefore, if the converter is operating or the start signal is active, the inverter will refuse to save.
Er2 - how to fix Mitsubishi FR inverter error
First, stop the converter and check the value of the write lock parameter. Setting it to 2 enables writing in any control mode. After stopping the inverter, re-attempting to change parameters usually proceeds without issue.
If the error persists, contact a professional service: inverter repair.
Error Er3 - calibration error
Er3 - possible cause of Mitsubishi FR inverter error
Error Er3 indicates too small a difference between zero offset and analog input gain. This points to a problem with input calibration, incorrect parameters, or an incorrectly applied analog signal.
Er3 - how to fix Mitsubishi FR inverter error
Check the calibration settings - parameters C3, C4, C6, and C7. Correcting them helps restore proper analog input response.
If the error keeps recurring, contact a professional service: inverter repair.
Error Er4 - incorrect operating mode
Er4 - possible cause of Mitsubishi FR inverter error
The inverter displays Er4 when the user attempts to change a parameter in NET communication mode, even though the settings do not allow writing. Most often, the write lock parameter is set to a value other than "2".
Er4 - how to fix Mitsubishi FR inverter error
First, check if PU mode is currently selected and if the write lock parameter has the correct value. After switching the mode and verifying the settings, the parameters can be entered again.
If the problem persists, contact a professional service: inverter repair.
Error rE1 - parameter read error
rE1 - possible cause of Mitsubishi FR inverter error
Error rE1 indicates that the inverter encountered a problem while reading data stored in the operating panel's memory. This refers to an E2PROM memory error, which prevents correct transfer of settings. The error usually appears when copying parameters from the panel to the inverter.
rE1 - how to fix Mitsubishi FR inverter error
The appropriate step is to re-execute the copying procedure. If the message reappears, check if the operating panel is functioning correctly.
If the problem persists, contact a professional service: inverter repair.
Error rE2 - parameter write error
rE2 - possible cause of Mitsubishi FR inverter error
The inverter reports rE2 when the user attempts to copy parameters while the device is running, or when an E2PROM memory error occurs in the operating panel during data writing.
rE2 - how to fix Mitsubishi FR inverter error
Stop the converter and then reattempt to copy the parameters. It is also important to monitor the operating panel, especially the FWD and REV LEDs. If the operating panel is unstable, it should be tested or replaced.
If the problem persists, contact a professional service: inverter repair.
Error rE3 - parameter setting verification error
rE3 - possible cause of Mitsubishi FR inverter error
Error rE3 means that the parameter values in the operating panel differ from those stored in the inverter. Inconsistency or an E2PROM memory error may also be detected during verification.
rE3 - how to fix Mitsubishi FR inverter error
It is best to start by re-verifying using the SET button. If the error does not disappear, you can repeat the full parameter checking procedure and compare the values from the source device. The problem may also lie in the operating panel, which should be checked.
If the problem persists, contact a professional service: inverter repair.
Error rE4 - incorrect converter model
rE4 - possible cause of Mitsubishi FR inverter error
The inverter registers rE4 when parameters are copied or verified between different converter models. Even a small difference in the device version can stop the write process. The error also appears when parameter reading is interrupted or the operating panel loses power during copying.
rE4 - how to fix Mitsubishi FR inverter error
The first step is to ensure that both devices belong to the same series and support the identical range of functions. It is worth checking the model compatibility, and then copying the parameters again, in the correct configuration. If the operating panel had its power disconnected, it is advisable to restart the set and repeat the copying procedure.
If the problem persists, contact a professional service: inverter repair.
Error Err. - message about incorrect signal status or communication
Err. - possible cause of Mitsubishi FR inverter error
The Err. message does not always indicate a fault. Most often, it appears when the RES signal is active, which prevents the system from operating normally. It often also indicates a lack of communication between the PU panel and the inverter, for example, due to a loose cable or an incompletely inserted connector. In some cases, the message appears temporarily when switching on the main circuits, when the control circuits and the power circuit are supplied separately.
Err. - how to fix Mitsubishi FR inverter error
To clear the error, switch off the RES signal and check that the connection between the PU panel and the inverter is stable. If the cables are correctly connected and the message still appears, it is worth restarting the inverter and observing whether it only appears when the circuits are switched on. Sometimes, this is not an actual fault, but merely a transient state resulting from the order of switching.
If the problem persists, contact a professional service: inverter repair.
