Okay - so I'm making progress on this little project. First, our marina shore power is 20 amps. I was told this by a neighbor and looked at the breaker panel. All breakers are indeed 20 amps. So I got that goin' for me.
Now, being the glorious hack I am, I bought a locking 3-prong plug for the boat end and connected it to a standard heavy duty extension cord for the shore connection. I then dropped 12/3 wire into the boat from the shorepower plug down into the dinette seat where the batteries are stored. I then wired in a GFI plug to test....plugged it in to the shore power....and....I had indeed successfully built a much more complicated extension cord. I got the powa.
To reiterate my planned use: I want to add two GFI outlets, one in the dinette seat area with the batteries (for a charger) and one in the forward hanging locker (for a light, etc.). Very simple stuff. The boat is in a fresh-water lake and will only use my slip's 20 amp power.
Now for all the stupid questions as I try to finish this up. Bear in mind, I understand a little about electrical work, but am still missing very basic pieces of the AC/DC puzzle...so here goes...
1. I don't get the whole ground thing as it relates to my boat. If I had an inboard motor, I do get running a ground wire from the buss to the engine and calling it done. But at this point, my buss is not really grounded to anything. I only have DC house power (no starting) and everything has worked fine thus far. But, now that Dog has mentioned running the ground from the AC into the DC buss, it's got me wondering. Should I run a ground from the buss to something else? Though I don't know what it is, there is a 1/8" threaded stud in the floor of the engine compartment that is not being used for anything.
2. What drives the need for the AC circuit breaker in the boat? Keeping in mind the fact that I'm on a lake and will use the exact same setup all the time, and taking into consideration that my shore power outlet is already on a 20 amp breaker at the shore box, is it really necessary to add another 20 amp breaker in the boat? And if so, why? I guess in thinking about my single circuit needs, and having used an extension cord for two years for all AC needs, I'm trying to understand the need for more complexity in the system.
3. What are the pros/cons of running cabin lights off the batteries while they are being charged in the slip? Does this hurt anything? If not, is there a good reason to add an AC light? Dog also mentioned a scenario where you might want to have AC power without having the DC side energized. I guess I could just unplug the charger in this case right?
4. Is it cool to wire the charger into the buss to charge the bank? Or should it go directly to the battery?
5. What the hell are these 3-pin outlets? They seem to have been wired with 14/3 at some point. Are they AC outlets or com ports?
Nothing has blown up yet. But I'm pretty sure that MaineSail would weep if he saw my work.
(PS - How about that bitchin' new SN battery switch? Yeah baby!)