All right, Stu. I will bow to your relentless pressure and explain the electrical fire.
When I bought the boat, the AB refridgeration was wired directly to the battery, protected by a circuit breaker of course.
I wasn't necessarily fond of this approach but in theory there is nothing wrong with it. Minimize the voltage drop from the source to the load. I have other loads, my windlass and my inverter, which also don't go through the panel. In fact, both have switches on the side of the seat forward of the sink.
What I didn't like was having a breaker as the switch buried under the outboard cushion and having to lift the cushion and the lid while reaching over the table just to turn off the fridge. That, and I had no visual indication of whether the fridge was on or off.
So I decided I wanted to have a lighted switch right next to my windlass breaker and my inverter disconnect.
Now I know what you are thinking Stu. The humorous among us are thinking at this point, why go to all the trouble of installing a switch and starting an electrical fire when you have the control knob right there with handy access inside the icebox?
The short answer is, a long answer. But mostly I just wanted a glowing warning light that I can see as I'm shutting up the boat on a Sunday night and dropping in the hatch boards so I don't drain the batteries. That and I don't like the idea of the fridge being turned on at a different setting every time and having the milk freeze or the ice cubes liquidy. It's a delicate thing. A man ought to wire his fridge according to his personal preferences.
So I got the perfect little switch. A surface mount affair with a round barrel because cutting a perfect rectangle through the two layers of fiberglass in this area is tricky business. The terminals I would have to connect blind because I can't my head in there.
Now the markings on the terminals were highly suspect. No instruction sheet. All rather vague. So I trusted nothing and whipped out my hand multimeter and started testing continuity in the both the switch positions so I would be absolutely sure to wire it correctly.
In fact, so confident was I working on this circuit with a breaker in line, that I really gave it no thought as I jumped a little negative lead over from the battery to the switch. I didn't even really consider that I had two circuits in play, the fridge circuit and the switch light circuit. Only one of these was actually protected.
So I tightened everything up, admired my handiwork, and flipped the switch to turn the fridge on...
If you have never wired in a dead short across a battery before, I would highly recommend it. It really helps you dispell the notion that working with 12V is not dangerous. Sure your not likely to get a big shock, but if you screw up, you can really run some impressive current and make short work of insulation and indeed even #10 wire. It's an impressive sustained flash and the smoke draws crowds from all down the dock.
I would not want to wire in a dead short with 4/0 wire. That might get nasty.
Anyway, I got a new switch. And an inline fuse. And some fresh wire. All is well.
