I'm currently installing A Helix DSP Mini. The manual makes no mention of using a fuse for this unit. It only instructs to run at least an 18 AWG to positive battery terminal. I used a 16 AWG and tapped into the amps 4 AWG power wire ferrule at amp which is fused at the battery. The manual states that the current draw is 400mA and max remote output current is 500mA. What size inline fuse would be adequate? Is it necessary? Thanks in advance