What is Reddit's opinion of AUTEK DC DC Converter Buck Module 12V/24V To 5V 3A USB Output Step Down Voltage Regulator Charge Compatible for iPad iPhone 4S 5 6/6 Plus etc (Standard USB)?

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I just wired One of these into the aux circuit on my Road King and stashed it in the headlight nacelle. I can run the phone charging cord down the handlebars and plug it in, and it all stays out of sight when I’m not using it.

The plan is to have the whole setup being run from one or two 12v dry cells, the kind that are used in UPS back-up systems.

I can pretty easily get power to the relay boards from a separate 5v source like this and I'll just get a 2nd one for pi itself.

Thanks for your input!

The main reason we chose 12V is because we figure it would be easier to find a 12V wind turbine with the power we need rather then look for a 6V turbine. How much power loss do you think this would cause? I don't see a data sheet. http://www.amazon.com/Autek-Converter-convert-adapter-DCCON-5U-0/dp/B00BMIVFK8/ref=sr_1_3?ie=UTF8&qid=1438743762&sr=8-3&keywords=12v+to+5v+converter

EDIT: i also saw on the webpage > Synchronous rectification, the conversion rate is 96% or more, very low heat.

Yes, you can split the 12v DC rail from the screen and downvolt one of them to 5v using something like this and run that to USB. I was working on doing just this with mine but instead opted for a battery pack that had the needed 5v2.1a USB out and a 12vDC out on one 20000mAh battery unit to make it portable.

https://www.google.com/search?q=DC-DC+converter+USB+output

https://www.amazon.com/Converter-Module-convert-adapter-DCCON-5U-0/dp/B00BMIVFK8

~~Something like this may be the easiest.~~

~~https://www.amazon.com/dp/B00BMIVFK8~~

~~http://www.ebay.com/bhp/12v-to-5v-usb~~

You could get a buck converter like this. That's convenient because the Raspberry's are powered from USB (right?). That particular model provides 3A @ 5V, which should be plenty for the model B. I don't know what the terminals on your battery are like, but you could get some crimp-on terminals or clips for this converter and just hook it up to the battery in the field.

The one thing this is missing is a fuse... Probably not the end of the world, but I like to protect my gear. You'd want something in series on the positive terminal (red wire), so hooking something like an inline fuse holder in series at the end of the red wire with a 3A fast-blow fuse would do the trick.

Maybe that makes sense..? :-)

Only 16 hours of use in 2 days. The DC converter would be: http://www.amazon.com/Autek-Converter-convert-adapter-DCCON-5U-0/dp/B00BMIVFK8/ref=sr_1_3?ie=UTF8&qid=1438743762&sr=8-3&keywords=12v+to+5v+converter

From what I've seen, Mausberry has sold out of the car power supply switches. I get the feeling they've moved onto new stuff and won't be making more of them, but I'd be okay with being wrong about that.

I have that same TFT touchscreen thing, and am looking to put it together in my car as well (though I may use an /r/ODroid C1 instead of an RPi, but that's another discussion).

From a different online discussion of Pi Carputers (don't have a link handy, if I find it, I'll edit it in later), I found a 12V to 5V USB power converter (here's an example: http://www.amazon.com/Autek-Converter-convert-adapter-DCCON-5U-0/dp/B00BMIVFK8/) which can provide always-on or switched power.

There are several discussions of using GPIO to cue the RPi to gracefully shut itself off, especially on StackExchange (http://raspberrypi.stackexchange.com/). There's just a lot of homework to do here.