The OTC DAIHEN MR315 and MR400 welding machines are commonly used equipment in industrial sites. To help you quickly resolve abnormalities during equipment operation, we have compiled the common fault phenomena, cause analysis, and troubleshooting methods for this series of welders. You can refer to the table below for preliminary inspection to reduce downtime.
I. MR315 / MR400 Welder Common Faults Troubleshooting Chart
| No. | Phenomenon | Cause | Troubleshooting Measure |
|---|---|---|---|
| 1 | Main power indicator is OFF | Control power switch S1 fault | Replace switch |
| Indicator PL1 fault | Check indicator | ||
| Phase loss in input wiring | Check distribution box fuses, wiring, etc. | ||
| Auxiliary transformer T5 fault | Check auxiliary transformer | ||
| 2 | Turn “Control Power” switch ON, fan does not run | Fan FM fault | Replace fan FM |
| Fuses F1, F2 blown | Replace fuses after eliminating short circuit causes | ||
| Phase loss in input wiring | Check distribution box fuses and wiring | ||
| Auxiliary transformer T5 fault | Check auxiliary transformer | ||
| 3 | Current uncontrollable | Remote control pendant fault | Check or replace remote control pendant |
| Printed circuit board C0015P00 fault | Replace printed circuit board | ||
| Hall sensor CT1 fault | Check Hall sensor | ||
| Thyristor SCR1, 2 fault | Check thyristors | ||
| Auxiliary transformer T2~4 fault | Check auxiliary transformers | ||
| 4 | Abnormal indicator PL2 is ON, no current | Exceeds rated duty cycle | Idle for 10 minutes to cool the welder |
| Ambient temperature at welder location is too high | Move to a cool, ventilated place; avoid direct sunlight and heat sources | ||
| Fan FM does not run | Check if fan is faulty | ||
| Thermal switch THP1 fault | Replace thermal switch | ||
| Printed circuit board C0015P00 fault | Replace printed circuit board | ||
| 5 | Ammeter pointer does not move | Ammeter DCA1 fault | Check ammeter |
| Printed circuit board C0015P00 fault | Replace printed circuit board |