Why Multioperator? In many cases, buying or renting individual welding power sources is impractical because of space constraints, transportation costs and primary wiring costs. As a result, contractors and engineering firms often opt for a "multi-arc" welding system. Such systems power more than one welding arc from a single primary power connection. When new construction, maintenance and repair demands a large number of welding arcs in a concentrated area, a multioperator power source saves you time, space and money.