Home 110 to Car 12V





Introduction: Home 110 to Car 12V

This is my first instructable. This lets you use a 12volt car plug-in at home, using a 12V plug (wall wart). The initial steps are how to do it for free with stuff around the house, You can make a cleaner one from bought parts. The only thing I an unsure about is the MA (mili-amps?), I have had no trouble using my adapter on any car powered device, but I am not responsible for any problems, broken devices, electric shock, etc. (anything).

If you see any problems, I will never be too proud to make any necessary adjustments

Step 1: What You Need

You need one(1) of each of these:

1. Standard 110 standard US home outlet (don't know if it will work in other countries)
2. 12V home plug
3. Car adapter (12V)
4. Multi-tool (wire stripper, crimper, etc.)
(Optional) A car plug "cup" adapter

Step 2: What You Do

I would recommend doing all this with the "wall wart" unplugged (especially those with heart problems).

Take the wire from the 12V adapter, and cut the wire just before the end of the cord (where you plug it into something).

Next strip the covering off enough wire to connect it to the car adapter.
(Note: the end contact will always work, but only one of the side contacts works (usually)

I connected the positive to the end contact and the negative to the side contact.

NOTE: You can also buy a car adapter cup, (positive for the middle, negative for the outside contacts) for clean reuse, less resistance, and less strain on the devices. Then clean-up everything with electrical tape or shrink wrap. (the importance brought to my attention by LasVegas)
This method Extremely encouraged for those with any heart problems.

Step 3: Working!

Your homemade adapter should now work fine.

I am a novice to electricity, but love finding how things work, so created this adapter. I am not responsible for any damages or injuries you may get while trying this out.

I saw the electrical writings, and figured it would work. I searched and didn't find anything, but do not know if anyone else has listed this before.

You could use a spare car power plug for easy car device swapping.



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    13 Discussions

    Glad to see you are trying things but I would really suggest you do battery powered stuff before you get onto mains stuff because it can be VERY dangerous if you do not fully understand what is going on.

    Here is some information about this project for you to consider that you may not already know about.

    Your wall wart has a power rating for example 12 volt 300 mA and if you try to connect a device which needs more power than this one of several things might happen.
    1/ If it has over current protection it will shut down.
    2/ If it hasn't it may overheat and even catch fire.
    3/ The device might simply not work because it is trying to draw more power than the wall wart can supply which will result in the voltage dropping too low.
    4/ If you had wired the lead so you had the plus and minus the wrong way round you could have damaged either the wart or your device or both.
    If you get more ideas might I suggest you post a question on the answers forum so others can advise before you try it? Don't want you to have an accident.

    1 reply

    wow that car was cool dude


    2 years ago

    now I like that

    Notes; 1. does appear that the fuse protection with the charger plug was defeated, With that defeated, any reverse polarity protection was defeated. Dumb luck may or may nor prevent damaging the charger by hooking up the wires one way and then the other if the first way didn't work. 2. Generally the wall wart shows the polarity of the plug, with a VOM or DMM you can then determine the polarity of the wires. 3. get a VOM or a DMM they are really inexpensive and will pay for itself. 4. Learn to solder or at least buy an assortment of small wires nuts to use with simple projects like this, or both. 5. Even if you let out the smoke in a few things along the way, you are on your way to be becoming an electronics hobbyist and or a hardware hacker. Do find yourself a mentor who you can ask questions of. 6. ALL of use here where novices once and still may be in some things.

    Better option... Go to your local Auto Parts Supply and pick up a replacement auto lighter outlet. Connect it to the wire from your Wall Wart and seal it with electrical tape, shrink tubing or epoxy. Then you have a safe port to plug the charger adapter into.

    5 replies

    That is an option I had thought about and is listed in my instructable.

    IMO, you should have done it that way rather than mentioning it as a possibility. It's just wrong to instruct on how to do something the wrong way. Bare wires twisted into place introduces added resistance (heat), a danger or shorting and potential damage to the electronics due to either of the aforementioned dangers.

    Damn, you are just ragging on everyone. It's just a quick and useful hack. Give him a break.

    Vegas is right its quick but not too safe he's just trying to help lesson in life - never take anything too seriously

    I understand your comment and have added this to my step 2 ( the building it step), to address your concern.

    This would work in any country you would just need a wall wart for the voltage in that country, however your one would work in any country (that I know of I think they are all between 100 and 240v).