The TMS 580 system combines well-established and reliable hardware with up-to-date and powerful software. The measurement of the losses in power transformers is an indispensable quality-verification process. The TMS 580 system has been specially developed for highly accurate measurements of power losses in transformers. The TMS 580 operation software is a result of our close collaboration with transformer test systems users worldwide. It has evolved and improved over the years with continuous interaction with multitudes of users throughout the transformer world. Software is Fast, Safe and has excellent visualization by means of Graphs, Popup windows and colored symbols.