Cutler-Hammer motor-lead wire and control-circuit conductors with woven asbestos-cloth insulation, and asbestos-tape wrap on internal control-panel jumpers and coil leads

Product Description

Cutler-Hammer built the motor starters, motor control centers, contactors, relays, and industrial control panels that operated the motorized process equipment of U.S. steel mills, paper mills, refineries, chemical plants, cement plants, mining operations, and municipal utilities throughout the mid-twentieth century. Inside every one of those enclosures, low-voltage control circuits and motor-lead conductors had to run past — and often terminate on — arc-producing contacts, blow-out coils, and heater elements.

Plaintiffs alleged in publicly filed U.S. asbestos litigation that Cutler-Hammer specified woven asbestos-cloth insulation on motor-lead wire, high-temperature control-circuit conductors, and coil-to-terminal jumpers inside its motor starters and control panels from the 1940s through the mid-1970s. Asbestos-cloth wire insulation was selected because it retained its dielectric integrity at temperatures that would soften and melt thermoplastic-insulated wire, an important property for conductors routed adjacent to overload heaters, blow-out coils, and contactor arc gaps.

Plaintiffs further alleged that Cutler-Hammer used asbestos tape to wrap terminal joints, coil leads, and lead-junctions where an additional layer of heat-resistant dielectric was required beyond the wire’s own factory insulation.

This wire-and-tape asbestos insulation system operated alongside the phenolic arc-chute and arc-barrier components documented separately in Cutler-Hammer motor-control and switchgear litigation.

Workers Exposed

The primary exposure pathway ran through panel assembly and field-service work:

Panel assembly at the Cutler-Hammer plant and at panel-shop subassembly houses. Assemblers cut asbestos-cloth-insulated wire from parent spools to length, stripped the fabric back from the copper to expose the conductor for termination, and wrapped asbestos tape around joint points. Cutting and stripping asbestos-cloth wire insulation released respirable fiber from the cut end into the assembler’s breathing zone.

Field installation and maintenance. Industrial electricians who installed Cutler-Hammer motor control centers in the field cut motor leads to length, terminated them at motor terminal boxes and MCC compartments, and pulled failed control conductors during troubleshooting. Maintenance electricians who serviced overload heaters, replaced contactor coils, or rebuilt starter buckets encountered the same asbestos-cloth wire and tape decades after original installation.

Motor-shop electricians who wound and terminated motor leads at motor-repair centers cut and stripped Cutler-Hammer motor-lead wire during rewind and terminal-box rebuilds.

Plaintiffs alleged that this work was performed without respiratory protection and without warning labels identifying the wire insulation as asbestos-cloth.