During the operation of the OTC DAIHEN EP400 welding machine, if a fault occurs, the display panel will pop up the corresponding abnormal alarm code. To assist maintenance technicians in quickly locating the problem, we have compiled a comprehensive troubleshooting guide covering common error codes from E000 to E911, along with official solutions.
OTC EP400 Abnormal Alarm Code Quick Reference Table
| Alarm Code | Abnormality Description | Solution / Countermeasure |
|---|---|---|
| E000 | Terminals [STOP] Disconnected | Confirm if the external terminal block TM5 [STOP] (34) is open-circuited. To clear the abnormality, set function [F4]. |
| E010 | Torch Switch OFF Wait | Confirm if the torch trigger/switch is stuck in the ON position upon startup. |
| E020 | Inching Feed OFF Wait | Confirm if the wire inching switch is stuck in the ON position. |
| E030-E037 | USB Communication Error | Check the USB drive connection, re-insert it, and restart the power. |
| E040-E042 | Startup Communication Error | This will disappear upon restarting the power supply. |
| E050-E059 | Control Board Communication Error | This will disappear upon restarting the power supply. |
| E100 | Control Power Supply Error | Check the +24V and ±15V power supplies. Restart the power. |
| E150 | Input Overvoltage | Confirm if the input voltage is within the 342-418V range. Restart the power. |
| E160 | Input Undervoltage | Confirm the input voltage is 342-418V. Check function [F20] settings. |
| E200 | Primary Current Detector Error | Check the contact status of the P30099P_CN25 connector. |
| E210 | Arc Voltage Detection Error | Check the welding cable and detection wire for open circuits or short circuits. |
| E220 | Primary Main Circuit Error | Confirm if the internal IGBT module is damaged. |
| E230 | Primary Drive Error | Check P30099P_CN21-CN24 connectors and test the waveforms. |
| E240 | Secondary Current Detector Error | Check the P30099P_CN29 connector on the circuit board. |
| E260 | Voltage Detection Loop Error | Check the P30099P_CN27 connector on the circuit board. |
| E301 | Primary IGBT Side Temp Error | Confirm P30099P_CN11 connector. Check the duty cycle and ambient temperature. |
| E302 | Secondary DR Side Temp Error | Confirm P30099P_CN12 connector. Check the duty cycle and ambient temperature. |
| E615 | Memory Backup Warning | Press any key to clear. Check if saved welding conditions have been initialized. |
| E700 | Output Overcurrent Error | Check if the contact tip is touching the base metal, or if the welding cable is short-circuited. |
| E710 | W-Phase Loss Error | Check the primary input cables and distribution wiring. |
| E800-E801 | Wire Feeder Encoder Error | Check the wire feeder control connections and motor status. |
| E810 | Wire Feed Motor Drive Temp Error | Check the torch and wire feeder for jammed welding wire. |
| E850 | Wire Feeder Control Power Error | Check P30087Q_CH2-CH1 24V power supply. |
| E860 | Wire Feed Motor Power Error | Check P30087Q_CH10-CH9 48V power supply. |
| E900-E907 | Software Error | If restarting fails to clear the error, please contact an authorized agent. |
| E910-E911 | OS Error | If restarting fails to clear the error, please contact an authorized agent. |


