An external power transmitter of an implanted medical device system such as a left ventricular assist device (LVAD) system and a method therefore are provided. According to one aspect, a method includes transitioning from applying a first external coil current limit to applying a second external coil current limit to limit current of an external coil coupled to the external power transmitter, the transitioning being based on at least one of an intent to enter a free mode of operation of the implanted medical device system, an existence of an alarm condition, and an existence of transcutaneous energy transfer system (TETS) power transfer.