A glass melting transformer provides an isolated electrical supply matched to the furnace heating process. Reference materials include dry-type and oil-immersed designs with output taps selected for the specified duty. The load must be identified before the electrical design is finalized: an electrode-fed glass furnace and a furnace using molybdenum disilicide heating elements can require different starting and operating arrangements. The transformer specification should therefore describe the actual load rather than only the furnace name. Input voltage, output voltage steps, current, phase arrangement and operating cycle form the basis of selection. Mechanical details such as the terminal layout, cooling method and installation clearance should be reviewed with the furnace designer. For a replacement unit, existing diagrams and nameplate data are useful starting points, but the current process requirements must also be checked. Send the furnace electrical diagram and the required start-up and normal operating conditions so that the proposed transformer can be coordinated with the heating system and its controls.