Predictive, or condition-based, maintenance offers companies the least expensive, most efficient method of reducing equipment-related downtime. Maintenance work is scheduled based on diagnostic evaluations that determine when to perform service. This differs from preventive maintenance, which is routinely scheduled whether the equipment needs service or not. Monitoring the condition of equipment provides trending data to help anticipate future maintenance needs. This paper examines 7 predictive maintenance technologies that monitor, assess, analyze, and inspect electrical equipment.