12v Outlet

[jclays]

Installed the cigarette lighter outlet in my cockpit.
Used 8ga wire(have a bunch) for the 6ft run. Fused 20a resettable inline breaker. Should be fine for my purposes.

 

[J0k3r]

Just my $.02, I would look at using something other than a cigarette lighter socket. Anderson make mountable sockets for their powerpole connectors in various sizes.

eg. Powerwerx PanelPole1, Panel Mount Housing for a Single Powerpole Connector with a Weather Tight Cover

That website has a lot of other options and is not the only source.

 

[TowLou]

What is the fuse size?

 

[gilbertpark]

Why not make life simple - find a 12v charger for your computer. I have one for my MacBook that works really well. Forget the inverter. Yes you will need a socket of some sort - I use a "cigarette lighter" socket fused to 10A. Gilbert

 

[High Wire]

To plug in your 300 watt inverter, first the 300 watts is the 120 VAC output of the inverter steady state. 300W divided by a guestimated 80% efficiency gives you about 375 watts of input DC needed to run the thing. Divide that by 12.0 volts is 31.25 amps DC. That's the MINIMUM I would size the DC wiring for if this is a permanent install. I would round up to 40A DC for the wiring. You can always size the fuse smaller. You have to take into account the entire round trip wire distance of the circuit. You said 15 ft from the source battery? The positive 15 ft and negative 15 ft would be 30 ft number for the ABYC table. 30 Ft at 40 amps at the 3 percent voltage drop (electronics) would be #4 gauge wire!!! An acceptable alternative for your laptop might be to use # 6 gauge and fuse it for 25 Amps DC, or #8 wire fused for 15 Amps DC. 15 Amps DC should be plenty for your laptop as long as no one plugs in a vacuum cleaner or blender. If they do then the fuse blows preventing turning the wires into a glowing bulb filament.

All of this sizing is explained the the back pages of the Blue Sea Systems Marine catalog.
And no way would I used a cigarette lighter plug/socket. They get hot pulling 10 amps.

 

[koliver]

Why not make life simple - find a 12v charger for your computer. I have one for my MacBook that works really well. Forget the inverter. Yes you will need a socket of some sort - I use a "cigarette lighter" socket fused to 10A. Gilbert

I have used a small inverter plugged into a cig lighter socket as the power supplier to my laptop for 20 years or more without issue. The incverter is quite small, probably smaller than the one the OP is planning to use, and has an on board fuse prominently displayed on its front.

I once decided to bypass the inverter by wiring a DC plug to my laptop directly, but an unforseen polarity difference caused it to burn up the wires attaching the GPS to the computer at one of the USB ports. Once the smoke has been let out of any electronic part, it is no longer functional, so once I had paid to replace the burned up USB to serial connector I was down a ways on that experiment and abandoned it. I returned to using the small inverter and have stayed with that system.

 

[Capt Ray]

Nice USB solution!

I have two of these 2+ years going great in the weather on our boat.

https://www.amazon.com/Scanstrut-Charge-Rapid-Waterproof-Socket/dp/B071WXWS9C/

ROKK Charge - Scanstrut - Amazon

Weatherproof even with "stuff" plugged into it.

IMHO: This company really needs to look at their marketing efforts because it does NOT come up when google searching or even searching on Amazon for this tpe of thing. But, once I found it and bought it, it is working well for us. Recommended.



12vdc to this device, two USB out in a weather proof enclosure.

Fuse with 3 amp and go one wire size larger (e.g. 14 AWG) than shown below.

 

[Jeff F]

Good morning

I will be installing a 12v cigarette lighter style outlet in the cockpit area of my Mainship 350. I will mostly use it to plug in a 350 watt portable inverter. I can run my laptop when on the hook and also run my Christmas lighting when underway.

Should I fuse the positive leg to the battery?

How should I calculate the fuse size?

Thanks

Jim.

Why not add a 110v outlet instead? You have a house inverter, right?

 

[backinblue]

I think 30A would melt most cigarette lighter outlets. I use something similar to this for my laptop. Note that it has a USB outlet as well so I can plug in my phone at the same time.

https://www.amazon.com/Outtag-Unive...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

 

[MVDarlin]

IMHO it is best to locate inverter as close to battery as possible. DC current does not perform well over long distance. An alternate option is to locate a battery next to the point of use inverter to handle demand surge. Connect to your DC systrm with a dc to dc charger.

Recomnend you go with bigger inverter snd conect it to your entire AC system so you can run all appliances. Blue Sea sells an AC source switch with 4 positions. Off, Shore, Gen , Inverter.

 

[MYTraveler]

IMHO it is best to locate inverter as close to battery as possible. DC current does not perform well over long distance.

Although I generally agree, in some circumstances it may make sense to locate the inverter further away. In that regard, it is important to understand that length doesn't degrade the "performance" of DC so long as the cables are sized to accommodate the length of the run (times 2)