Always check the inlet carefully. Something could be very wrong!. If you click on the lower picture, you can see the insulation has melted off, and the wire has acquired a lovely green patina. Nice if you are a three hundred year old bronze vase, but bad if it's your boat's marine wiring. That's the neutral wire that has been fried. Once upon a time it was white. You can click on both pictures for a better view of the damage.