Abstract: A three-phase multiple sequence welding controller includes a single unit controller having three distinct welding sequence control modules and three distinct machine logic control modules integrated into a single unit. The single unit controller preferably includes a single microprocessor, which incorporates the six distinct control modules. The single unit controller is preferably mounted with a plurality of input/output ports and control circuitry onto a single unit circuit board. The single unit controller is capable of controlling three welding machines along with a network of peripheral machines.