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Discussion Starter #1
After I sent my cigarette outlet to Finland to have a start button installed by vantaam5, I decided I needed an alternative power source. I thought, hey, why not add an AC outlet. Some cars have it stock. And while I'm there, why not add a powered USB plug as well! :hihi:

Tools required:
Screwdriver
Soldering Iron
Dremel

Parts needed:
DC to AC/USB plug thing
AC snap-in receptacle
Probably extra USB socket and some wire

This is the DC to AC/USB plug I used bought from amazon:

Amazon.com: Universal 12V DC to 110V-220V AC Power Inverter plus + 5V USB Adapter: Home Improvement

This is where I got the AC receptacle:

http://www.mouser.com/catalog/629/889.pdf

Now for the process and pictures:

1) Remove stow tray from center console
This is done by removing cup holders, options control unit, a/c unit and frame, then trim panel around shifter.
There are a lot of pieces to remove to get one small thing out, but after a few times it only takes a few minutes.



2) Once removed, dremel out the slot for the ac receptacle to fit through. I ended up using the soldering iron to melt away the plastic and got much better results and it was much easier. Just do it in a well ventilated area.



3) Tear down the DC-AC adapter and solder off the wires that connect to other components, not from the board.
I reused the housing on this unit to protect the circuit board and such.



4) With AC and USB outlets placed in the tray, solder the wires from the DC-AC adapter to the outlets. I used more wire here for the extra flexibility and length.






5) Make room for the DC-AC adapter unit under the tray. Then I cut the wire connector off of the cable that used to power the cigarette outlet. The largest wire here (red and other colors) is the power cable. It carries close to 15V. The smaller multicolor cable is for the amber LED around the cig outlet. It carries around .024V. Connect these to the DC-AC adapter in the correct places. (Should be red=power, black=ground. The BMW brown cable is ground.
DISCONNECT BATTERY. 15V WILL END YOU


6) Reinstall everything and enjoy. I forgot to take pictures, but there is a plastic layer that sits directly below the tray. Another tray of sorts to support the tray. I dremeled away a small section, maybe 1.5" x 1.5" for the power outlets to extend all the way down to the carpet underneath. This was very easy.




I have more pictures if anyone wants to see more. Ask any questions. I am no electrical expert. This DIY is fairly straight forward. It got late tonight so I am not 100% finished. I need to do some final soldering tomorrow.

ENJOY! :cheers: And always be safe, I am not responsible for you guys messing up your cars or hurting yourselves!
 

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Discussion Starter #3
I'm sure its on its way!
 

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GREAT WRITEUP, im sure many will find this useful for those "oh crap i forgot to charge..." moments. (ahem AA batteries for me, haha)

+1

Dan if you decide to do this let me know and Ill pay half your supplies if you help me with mine?
 

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Discussion Starter #7
And sorry if it looks sloppy, my DIY skills are sub par. My dremel came in the mail yesterday so I had ZERO experience with it. In all honesty, the dremel wasn't very helpful as the hole had to be fairly small.

Some of you talented craftsmen out there can probably do this much nicer than I did, just don't tell me how for a month or so or i'll be mad I didn't do it that way. :)

And I did the plug the direction it is so that one of the large rectangle plugs could fit in the outlet. My only concern is that small objects or trash can fall in the openings. Might look for a plug cover or something. I have some for USB outlets that works great already.
 

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And I did the plug the direction it is so that one of the large rectangle plugs could fit in the outlet. My only concern is that small objects or trash can fall in the openings. Might look for a plug cover or something. I have some for USB outlets that works great already.

Good idea on the plug covers. Also good idea on the orientation of the plug to allow the "bigger" ac plugs to fit.
 

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Discussion Starter #9
Also, would have preferred the plug on the right side of the tray, but the duct that carries air to the rear of the car is under there. It was much more convenient to fit the plugs on the left side. Much less modification to the car itself.

Once I get my cigarette lighter back, there will be less room under the tray for the DC-AC adapter and I will most likely cut an area away from the foam that surrounds the shifter. I already cut a little out and I don't see a problem with cutting out more.
 

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i personally would try and find another location of installing it, like the rear cup holder. if it just had a prong sticking out of it. on the 540i I did something similiar but it was tucked under the armrest so you couldn't see it.

it does look good though, just curious, why the usb plug? does your phone use one to charge? or ipod would be my guess? If you had an ipod why not run a PIE ipod rca / power adaptor?



basically plugs into the bottom of the ipod to charge it and deliver sound. That's what I run currently ps...
 

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Interesting. Are you relying on the cars fuses/internal wiring to stop any surge/power issues? Or have you wired in some time of inline fuse?
 

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Discussion Starter #12
I have the DICE kit for my iPod. But I have other iPods I could charge and of course almost all phones charge through USB so yes, for my phone. Powered USB is becoming a major segment of the electronics market.
 

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For those of you who do this, please keep in mind that the AC plug in question probably can't provide more than about 1A @ 120V, and even that might be pushing it depending on the size of the wire / fuse on the cigarette lighter. I'd bet it is no larger than 10A @ 12V, which after conversion losses will be <1A @ 120V.

In other words: Don't get any funny ideas about plugging a portable fridge or anything like that into the outlet!

d-
 

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For those of you who do this, please keep in mind that the AC plug in question probably can't provide more than about 1A @ 120V, and even that might be pushing it depending on the size of the wire / fuse on the cigarette lighter. I'd bet it is no larger than 10A @ 12V, which after conversion losses will be <1A @ 120V.

In other words: Don't get any funny ideas about plugging a portable fridge or anything like that into the outlet!

d-
In all seriousness and forgive my niavete' but what about a lap top?
 

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Discussion Starter #16 (Edited)
For those of you who do this, please keep in mind that the AC plug in question probably can't provide more than about 1A @ 120V, and even that might be pushing it depending on the size of the wire / fuse on the cigarette lighter. I'd bet it is no larger than 10A @ 12V, which after conversion losses will be <1A @ 120V.

In other words: Don't get any funny ideas about plugging a portable fridge or anything like that into the outlet!

d-
Crap! The whole reason I did this was to power a kegerator and disco ball! Oh well.. :hihi:

In all seriousness, there is a fuse built into the power adapter. I did not see its rating. However I think it will be able to provide more than 1A @ 120V. Many people use laptops with these adapters, not that it is 100% advised. I would only consider this plug for lower power devices or higher powered devices in an emergency.

To add, my thinkpad needs 90W. The block says 2.5A-.5A @ 120V to 4.5A @ 20V for the laptop. However, 90W from a 120V outlet would only need .75A, less then the 1A doug mentioned.
 

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Discussion Starter #17
Interesting. Are you relying on the cars fuses/internal wiring to stop any surge/power issues? Or have you wired in some time of inline fuse?
Typically most DC cig lighter plugs have a fuse in the tip of the plug. On this adapter, there is a fuse built into the board to serve that purpose. Any DC-AC adapter you buy will have a fuse built in to prevent surges, etc.
 

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Crap! The whole reason I did this was to power a kegerator and disco ball! Oh well.. :hihi:

In all seriousness, there is a fuse built into the power adapter. I did not see its rating. However I think it will be able to provide more than 1A @ 120V. Many people use laptops with these adapters, not that it is 100% advised. I would only consider this plug for lower power devices or higher powered devices in an emergency.
Don't worry, it will be very clear very quickly if you overpower the wiring :)

To add, my thinkpad needs 90W. The block says 2.5A-.5A @ 120V to 4.5A @ 20V for the laptop. However, 90W from a 120V outlet would only need .75A, less then the 1A doug mentioned.
Don't confuse the output wattage with the input wattage. Output wattage is interesting information, but irrelevant to this conversation.

The input on your block says 2.5A @ 120V. This is 300W and is what would need to be provided by your outlet to the laptop transformer so that it can be inefficiently converted to the 90W required by the laptop. 2.5A >> than the 1A I mentioned.

Further, 300W @ 12V = 25A, and this is at 100% efficiency. You can plug that laptop into your outlet if you'd like, I don't be surprised to find yourself replacing the fuse, the wiring, or both.

If you want to power your laptop you would be much better off getting a DC transformer and stepping the voltage from 12V directly to 20V with a single loss of efficiency instead of 12V -> 120V -> 20V with 2 different losses of efficiency.
d-
 

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btw, the fuse is only 7.5A. 7.5A @ 12V = 90W. Try it if you'd like, but I don't think you can power a 90W laptop from a circuit that can only provides 90W before conversion losses.
 

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Discussion Starter #20
The input on your block says 2.5A @ 120V. This is 300W and is what would need to be provided by your outlet to the laptop transformer so that it can be inefficiently converted to the 90W required by the laptop. 2.5A >> than the 1A I mentioned.

Further, 300W @ 12V = 25A, and this is at 100% efficiency. You can plug that laptop into your outlet if you'd like, I don't be surprised to find yourself replacing the fuse, the wiring, or both.

If you want to power your laptop you would be much better off getting a DC transformer and stepping the voltage from 12V directly to 20V with a single loss of efficiency instead of 12V -> 120V -> 20V with 2 different losses of efficiency.
d-
Wise words. I seem to have difficulty measuring current with my multimeter. I know it is done in series to the circuit, but when I tried on the car wiring for the cig lighter, I got sparks. :eek:h: Any idea on the setup I installed, how I can test the current available at the AC plug? This way I can settle it once and for all and know what I can plug in or not.
 
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