Why is it important for metal cabinets housing electrical equipment to be grounded?

Grounding metal cabinets housing electrical equipment is crucial primarily for safety reasons, specifically to minimize shock hazards. When metal enclosures are properly grounded, they provide a path for electrical current to safely dissipate into the ground in the event of a fault, such as a short circuit or insulation failure. This significantly reduces the risk of electric shock to personnel who may come into contact with the equipment, as a grounded cabinet will not retain a dangerous voltage.

While grounding may also have implications for performance and noise reduction, those aspects are secondary to the primary function of grounding as a safety measure. Preventing corrosion is typically addressed through other means, such as using corrosion-resistant materials or coatings, rather than relying on grounding for that purpose.