In daily welding operations, the OTC DAIHEN W400 welding machine may encounter some common operational or setting abnormalities. To ensure your production efficiency, we have compiled 15 common simple faults of the W400 welder along with their corresponding troubleshooting and treatment methods. When the equipment malfunctions, you can directly refer to the table below for preliminary inspection and repair.
I. W400 Welder Common Faults Troubleshooting Chart
| No. | Fault Phenomenon | Cause of Fault / Abnormality | Troubleshooting Method |
|---|---|---|---|
| 1 | Power switch trips (Breaker trips) | Electrical leakage or internal short circuit in the power source. | Do not turn on the power switch again. Contact the authorized agent immediately for inspection and repair. |
| 2 | Even when power switch is ON, main power indicator does not light up | Primary side power is not input or input is abnormal. | Supply primary side power within the range of 380V±10%, and check the distribution box power supply. |
| 3 | Even when power switch is ON, left/right digital meters show nothing | ||
| 4 | “Temp Abnormal” LED lights up and shows error code when power switch is ON | Temperature abnormality protection circuit is activated (Overheat). | Do not perform any operations (Keep the power ON), let the cooling fan run for at least 10 minutes to dissipate heat, then turn off the power. Afterward, clean the dust inside the welding power source. |
| 5 | Shielding gas is not released (No gas flow) | Gas cylinder is closed. | Open the gas cylinder valve. |
| Insufficient cylinder pressure. | Replace with a new gas cylinder. | ||
| External input setting/processing error. | Confirm whether the settings of internal functions F29~F32 are correct. | ||
| External input wiring is broken/short-circuited. | Confirm there are no abnormalities in the wiring connected to the external input terminal block. Repair or replace if necessary. | ||
| 6 | Shielding gas release does not stop (Continuous gas leaking) | External input setting/processing error. | Confirm whether the settings of internal functions F29~F32 are correct. |
| External input wiring is broken/short-circuited. | Check the wiring on the external input terminal block. Repair or replace if necessary. | ||
| 7 | Welding conditions set correctly, but arc does not strike (No open-circuit voltage) | Torch cable connection is loose. | Connect the torch cable securely. |
| Torch switch is faulty. | Confirm if the torch switch functions normally. Replace if necessary. | ||
| 8 | Cannot set current value / voltage value | In automatic machine mode. | Confirm if the setting of internal function F4 is correct. |
| Analog remote control pendant (optional) is connected. | When a remote control pendant is connected, settings on the remote take priority. Please adjust on the remote. | ||
| Encoder is faulty. | Circuit board PCB2 (P30086R00) needs to be replaced. | ||
| 9 | Mode does not switch even when “Crater Fill” key is pressed (LED doesn’t move) | Internal function F45, F48, or F51 is set to “ON”. | Change these internal function settings to “OFF”. |
| 10 | Cannot set welding conditions on the control panel | The misoperation prevention function on the panel is active (Key Lock is ON). | Press and hold the “Execute” key for more than 3 seconds to unlock the panel keys. |
| Cannot switch welding modes on the control panel | |||
| 11 | Unstable Arc | Welding mode selected incorrectly. | Verify if the wire diameter, wire material, and shielding gas settings match. |
| Defective wire or abnormal wire feeding. | Check if the welding wire is rusted, and if there are anomalies in the feed rolls or wire liner. | ||
| Voltage detection wire is not connected correctly. | Confirm the voltage detection wire is connected correctly and securely. | ||
| Noise interference mixed in voltage detection wire. | Adjust the arc characteristics towards the positive direction. | ||
| Circuit board P30205S fault. | Contact the agent or our sales office for repair. | ||
| 12 | No wire feeding (And no error code displayed) | Pressure roll of the wire feeder has fallen off. | Reinstall the pressure roll correctly (refer to wire feeder manual). |
| Wire feeder wiring abnormality. | Confirm whether the wire feeder’s control wiring is broken or has poor contact. | ||
| 13 | Porosity occurs in the weld | Poor shielding gas or insufficient flow. | Check cylinder gas level, and check gas hoses for leaks or blockages. |
| Torch contact tip severely worn. | Replace with a brand-new genuine original contact tip. | ||
| 14 | WCR signal is consistently outputted on the robot-side monitor | WCR relay of the welding power source is faulty. | The WCR relay mounted on circuit board PCB1 (P30205P00) needs to be replaced. |
| 15 | Forgotten Password | – | Contact the agent directly for technical unlock support. |