Size transfomer for load This topic contains 1 reply, has 2 voices, and was last updated by John C 2 months ago. Author Posts March 14, 2019 at 2:34 pm #10207 Elias PorterParticipant I need a 480v/120v transformer to supply a load of 20KVA @120v, but I only want to use 1phase. Should I use a 1phase or 3 phase transformer? What connection? Cna I do this? March 18, 2019 at 7:33 am #10210 John CGalco Representative I believe you can, but going to suggest you give us a call at 800-575-5562 and ask for a product manager. They can hammer out the details with you and get you something that will do the job. Author Posts You must be logged in to reply to this topic.