OutBack Power FLEXmax FM80-150VDC Charge Controller - OutBack Power’s FLEXmax line of Maximum Power Point Tracking (MPPT) charge controllers provide unrivaled system integration where a high performance, efficient and versatile charge controller is needed. Both the FLEXmax FM60 (60 amp) and FM80 (80 amp) charge controllers will increase your photovoltaic array power yield up to 30% compared to non-MPPT controllers. Active cooling