5hp Single Phase Submersible Motor

All vfds can convert single phase to 3 phase.But beyond around 3hp at 230v, you have to double the size of the vfd.So for your 7.5hp motor, you will have to use a 15hp vfd.Also consider this a 7.5hp 230v 3 phase motor will be around 22a flc.That means it will be drawing 38a from the single phase line when fully loaded.