Battery powered welding system

A battery powered welding system comprising:

• a MIG torch for performing a welding operation;
• control circuitry configured to control a welding power output converted from power from an external battery power source;
• a wire feed speed control circuitry comprising a pulse width modulation wire drive motor control circuit configured to generate one or more signals to regulate a voltage in a wire drive motor based on a reference wire feed speed level selected by the operator;
• and
• a wire drive assembly coupled to the wire drive motor control circuit and to the control circuitry and configured to feed a welding wire using power from the external battery power source.

An externally powered welder comprising:

• a welding power converter configured to receive power from an external power source;
• a weld output controller configured to control welding power output of the welding power converter;
• and
• a wire drive controller configured to control a wire drive assembly;
• and
• a polarity change-over device configured to reverse a polarity of the welding output power between a work clamp cable and the welding torch.