Presently disclosed embodiments are directed to an adjustable-speed drive comprising a transformer module and an inverter module configured for installation in either of a side-by-side or stacked configurations. The disclosed embodiments utilize a modular design for the transformer and inverter modules. Thus, the adjustable-speed drive is capable of being installed in either of a side-by-side configuration or a stacked configuration. This modular design allows for installation at a site in accordance with the space limitations of any given location.