Lincoln Electric POWER MIG 255 SVM144-B User Manual
Power mig 255, Svm144-b, Service manual
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Table of contents
Document Outline
- Master Table of Contents
- Safety
- Section A - Installation
- Section B - Operation
- Section C - Accessories
- Section D - Maintenance
- Section E - Theory of Operation
- Section F - Troubleshooting & Repair
- Symptoms
- Major Physical or Electrical Damage is Evident
- Machine is dead — no open circuit voltage output and no wire feed when gun trigger is pulled. The machine display may be lit.
- No open circuit voltage output but wire feeds normally when gun trigger is pulled.
- Wire feeds but welding output is low causing wire to “stub”. Welds are “cold”. Machine cannot obtain full rated output of 200 amps at 28 volts.
- The output voltage and wire feed is present continuously or pulsing when gun trigger is NOT activated.
- The output voltage is present continuously when gun trigger is NOT activated.
- No control of arc voltage. Wire feeding is normal.
- There is no gas flow when gun trigger is pulled. Wire feeds and weld voltage is present.
- The machine stops feeding wire while welding.
- No control of wire feed speed. Other machine functions are normal
- There is no wire feed when gun trigger is pulled. Normal open circuit voltage is present.
- The arc is unstable and or “hunting”.
- Weld bead is narrow or ropy. May have porosity with electrode stubbing into plate.
- The contact tip seizes in the gas diffuser.
- The welding arc is variable and sluggish.
- The arc striking is poor.
- Section G - Electrical Diagrams