Product Description

The Square D Model 6 motor control center, and its Model 4 and Model 5 predecessors, was one of the most widely installed MCC lineups in North American industry from the 1950s onward. Produced at Square D’s Cedar Rapids IA, Columbia MO, and Lincoln NE plants, the Model 6 assembled plug-in starter “buckets” onto a common vertical bus. According to publicly filed asbestos litigation records, the horizontal and vertical bus bars were allegedly seated on molded chrysotile-phenolic support blocks, and woven asbestos fabric barriers allegedly separated phase compartments; arc chutes above each contactor allegedly used chrysotile-phenolic plates.

Racking buckets, changing bus supports, and cleaning fault-damaged cubicles allegedly disturbed the asbestos content.

Workers Exposed

  • Motor control center technicians pulling and rebuilding Square D buckets
  • Industrial electricians (IBEW) commissioning and maintaining Model 6 lineups
  • Plant electricians replacing bus supports and interphase barriers
  • Industrial maintenance electricians cleaning MCC cubicles after arc-fault events