Do we "need" 120v on board?

[Anonymous7500]

I have developing a wiring diagram at an appropriate pace for a procrastinator. The concept is evolving based on web research as well as existing forum advice.

Originally, we had discussed installing a two burner electric cooktop after removing the existing alchohol-electric stove that was original. Unfortunately, the 1200 watt per burner consumption doesn't seem acceptable to extended periods of being disconnected.

That got me thinking, do I really need any 120v on the boat? Currently I am considering installing a 120v main breaker immediately down stream of the shore power connection, followed by a GFI 120v outlet (both located in the aft cockpit locker). Beyond that, everything on board will be 12v and I will replace the current 120v outlets with 12v outlets.

So far the only thing that we have "plugged in" has been a coffee pot, CD player and fan.

Is there are reason to have 120v on board that I am missing?

Thanks in advance!

[RunningLemur]

Our boat has no shore power at all. Depending on how you've got your 12v system designed then there's no need for 120v. With enough wind and or solar and a large enough battery bank the boat can be made entirely power self sufficient. In that case, why add the hassle of connecting to a common ground with everyone else's boat in the marina ?

[Florida Mike]

sooner or later you'll need to run a battery charger or some other power tool. Other than that 12 V should be good. I personally carried a heavy-duty extension cord. Just my two cents, Mike.

[colemj]

WARNING: THREAD DRIFT!

I initially read your first sentence as "I have developing a wiring diagram at an appropriate place for a procrastinator" and thought that my procrastinator runs on cocktails (and they have to be wired to the hammock)!

Mark

[Lake-Effect]

There are people living off-grid with just solar and wind to recharge their battery banks. If you can live without electric heating devices (electrical heater, blow-dryer, electric kettle, electric oven, etc) and other high-draw loads like air conditioning, you can theoretically get by without AC. Conversion to LED lighting, extra insulation on your cooler, etc will further reduce your 12v requirements.

But shorepower is darned convenient when it's available. it's the cheapest way to fully recharge the boat batteries, and AC-powered small appliances are common and inexpensive. A galvanic isolator will reduce the chance of accelerated electrolysis when connected to shorepower.

So, I think the ideal is to have minimal boat AC wiring, to be able to take advantage of it when available, but you should make little or no use of AC when away from shorepower, which means you don't need a big honkin inverter, or a genny that puts out AC.

[roverhi]

It mainly depends on whether you will have the need for AC powered tools. My boat was wired for 120VAC but it was a crappy job and scared me. I've ripped it out and installed an Inverter for my AC electrical needs. Just plug directly into that for my AC needs. Don't have AC at my slip. Have 260 watts of solar panels so the batteries stay up even though the panels are stowed vertical most of the time.

If you have AC at your slip, an extension cord will work fine as you'll mostly want it for a heater in late season and for battery charging. If you are going to run a microwave or other electronic gew gaws, then an AC system might be worthwhile.

[Anonymous7500]

Originally Posted by colemj

WARNING: THREAD DRIFT!

I initially read your first sentence as "I have been developing a wiring diagram at an appropriate place for a procrastinator" and thought that my procrastinator runs on cocktails (and they have to be wired to the hammock)!

Mark

Some of my greatest thinking happens with a cocktail in hand. At least that is what I believe at the time. Unfortunately, I don't usually remember the things that I thought.

Originally Posted by Lake-Effect

So, I think the ideal is to have minimal boat AC wiring, to be able to take advantage of it when available, but you should make little or no use of AC when away from shorepower, which means you don't need a big honkin inverter, or a genny that puts out AC.

That is the line of thinking that I am headed toward. I don't want a generator, but I think I will be including a modest inverter for the unexpected.

Originally Posted by roverhi

It mainly depends on whether you will have the need for AC powered tools. My boat was wired for 120VAC but it was a crappy job and scared me. I've ripped it out and installed an Inverter for my AC electrical needs. Just plug directly into that for my AC needs. Don't have AC at my slip. Have 260 watts of solar panels so the batteries stay up even though the panels are stowed vertical most of the time.

I briefly looked at the existing 120v and understand being scared. That is why we are ripping most of it out over the winter.

[capngeo]

Do we "need" 120v on board?

Dunno about "we", but I need 120VAC.

I spent a lot of time on large commercial vessels with big gennys that run 24/7, so I got used to having "power". Other than lighting and instruments, EVERYTHING electric on my boat is 120VAC. Most powered through an inverter, but can switch to genny power in an instant for the larger draw stuff. I generate power in DC to the house bank and then back to AC via a 5Kw inverter.

Why do you ask? Because I like cold beer, ice, air conditioning, heat, blenders, vacuums, microwaves, and all the other modern conveniences.

Yes, I'm that guy with the genny running over there.... c'mon over for a cold drink, and a frozen steak!

[Lake-Effect]

Originally Posted by Anonymous7500

I don't want a generator, but I think I will be including a modest inverter for the unexpected.

No disagreement. But the smaller the AC requirement, the smaller the needed inverter. Unless you're capngeo, who went to sea in his condo

[Jimbo485]

You don't "need" it, but it is handy.

It has nothing to do with whether you spend time in marinas or at anchor. If you want to use power tools, laptop or whatever, it is good to have an inverter. The final decision depends on you and the gadgets you reckon you need.

West Marine sell little inverters for $20 each that you can plug into the 12V plugs around your boat. Very efficient in one way because you don't have to have a great big inverter with an AC wiring network around the boat. Flexible, modular, disposable, cheap.