Lincoln Electric LF-72/74 User Manuals

Table of Contents

• Master Table of Contents

  6
• Safety

  2
• Section A - Installation - LF-72

  7
• Section AA - Installation LF-74

  43
• Section B - Operation LF-72

  27
• Section BB - Operation LF-74

  65
• Section C - Accessories - LF-72

  33
• Section CC - Accessories - LF-74

  71
• Section D - Maintenance - LF-72

  39
• Section DD - Maintenance - LF-74

  77
• Section E - Theory of Operation

  81
• Section F - Troubleshooting and Repair

  85
• Symptoms

  88
  • The wire drive does not feed wire and the drive rolls do not spin

    88
  • The wire feeds erratically, or the motor LED lights.

    88
  • The wire continues to feed when the gun trigger is released.

    88
  • No shielding gas.

    89
  • Variable or hunting arc.

    89
  • When the trigger is pulled, the drive rolls spin but no arc voltage

    89
  • The arc burns back to the tip.

    89
  • The gas continues to flow for a long time after the weld.

    89
  • The motor (L12081) failed when a load (6 N m) was applied to the wire drive.

    90
• Section G - Electrical Diagrams

  107