To size pwm charge controller Divide the total wattage of your solar panels by your system voltage (inverter voltage). whatever answer you get multiply the answers by 1.25(NSc safety code) that is your Current rating in Amps for a pwm charge controller. For mppt charge controller Divide the total wattage of panels by the open circuit Voltage of one of the solar panels. Whatever your answer multiply it by 1.25. whatever the result is current rating in Amps of the mppt.
The fuse Rating between solar array and charge controller is the equivalent to your number of parallel string multiply the Isc (short circuit current) of one solar panel in the array multiply by 1.25 (NSc code)