The cost penalties associated with traditional power supplies that operate at low power factor are overcome using an industrial power supply that can operate at near-unity power.
Reliability, controllability and capital cost have been the primary considerations in selecting power supplies for use in industrial heat-treating and other thermal-processing applications rather than power factor and operating cost. Reliability is important, as process cycle times are measured not just in hours but often in days, weeks and even months. A process interruption resulting from a power supply failure can result in tens of thousands of dollars of lost product and could result in equipment damage. Industrial power supplies are expected to have a life expectancy of 20 years or more. Controllability is important because the temperature within the furnace must be precisely controlled over a wide operating range. Temperature regulation requirements of I1 degree are common. Capital cost, or return on investment, also is an important consideration.