Carbon black and MV drives: contamination risk in tire plants

In tire production, conductive carbon black settles everywhere — including inside medium-voltage drive cabinets, where it builds into a latent fault risk.

Carbon black is essential to tire manufacturing — and hostile to electronics. The particles are fine, they travel with air, and unlike ordinary dust they conduct electricity. In a tire plant, some fraction always reaches the electrical rooms, and over years it settles inside drive cabinets: on boards, busbars, insulators and cooling paths.

Why conductive dust is a different problem

Ordinary dust mainly restricts cooling. Conductive dust creates leakage paths across surfaces that were designed to insulate. Combined with humidity, deposits can support tracking — small discharge paths that carbonize insulation and grow until they become flashover. In a medium-voltage drive, that endpoint is destructive. The deposits accumulate silently; the equipment runs normally until the margin is gone. That is what makes contamination a latent fault risk rather than a visible one.

A documented case

DUCHENG has published a service record from exactly this environment: at a leading tire manufacturer in Rayong, Thailand, medium-voltage drives with nearly ten years of service had accumulated conductive carbon-black deposits inside their cabinets. The systems were reconditioned fully on site by Ducheng Industrial (Thailand) Limited within a planned maintenance shutdown — deposits cleared, aging components addressed, and the equipment returned to service through controlled recommissioning.

What plants in similar environments can take from it

• —Contamination severity is only visible from inside — periodic internal inspection is the honest measure.
• —Cleaning contaminated MV equipment is specialist work: deposits sit on and around components that hold dangerous energy.
• —Large MV systems are rarely practical to ship out — planned on-site work during a shutdown window is often the workable path.