A modular X-ray source and method for replacement of such an X-ray source are disclosed. The source is inside a consumable modular enclosure where the entire assembly is swapped out during maintenance. The enclosure covers an X-ray tube, high voltage circuit boards 6 and cooling insulating oil are arranged inside the module enclosure. The enclosure structure includes an X-ray window, connector engagement alignment guide and electrical connectors. The modular X-ray source is used in a multiple source tomosynthesis imaging system where multiple pulsed X-ray sources are utilized. The easy replacement of X-ray tube assembly inside the consumable modular enclosure results in lower maintenance cost and overall reliable X-ray imaging machine. The modular source has potential to increase the machine volume in the field and create new standards for replaceable modular X-ray source.