Continuous smelting duty requires the output voltage steps and current schedule to be matched to the furnace. The source catalogue distinguishes on-load and off-circuit regulation. A furnace transformer supplies electrical power to an industrial furnace according to its process requirements. The reference catalogue covers submerged arc, steelmaking arc, ladle refining, electroslag and power-frequency furnace applications. These duties should be treated separately because their operating cycles, secondary voltages and regulation requirements differ. The selection process starts with the furnace type, rated power and required output range. Input voltage, phase arrangement, impedance requirements and cooling conditions are then reviewed with the furnace equipment supplier. Available catalogue tables provide reference configurations for each family, including ratings, dimensions and weights where stated. A listed configuration is not a promise that it fits every furnace with the same nominal capacity. For a new furnace or replacement project, send the electrical specification, operating cycle and connection requirements. The technical proposal will define the selected transformer arrangement and accessories. Installation dimensions and lifting requirements should be confirmed against the approved project drawing before site work begins.