Thread: Help!! How to protect fish finder

When I mentioned "foreign potential", I was not speaking of lightning. Any voltage not associated with the specific electronics circuit would be a foreign potential, for example a 24v TM potential would b be foreign to the 12v of the Sonar circuit.

This does happen.

Humminbird recommends a 3A fuse for the Helix 9. I wired my units directly to the battery and used this:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Originally Posted by GWDawg1

Humminbird recommends a 3A fuse for the Helix 9. I wired my units directly to the battery and used this:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I used the same fuse block at the battery.