On adding inside outlet for plugging in USB

[Carol H]

[QUOTE=MCDenny;444793

Your iPad will charge off a USB port but I'm not sure your Mac will.[/QUOTE]

MacBooks will not charge by USB as their chargers start at 60W an iPhone only takes 5W and IPad 10W to charge thus why a USB will do it.

[Huck]

I recently bought this. Haven't had a chance to try it yet.
PowerGen 4.2Amps / 20W Dual USB Car charger Designed for Apple and Android Devices

[Bob Miller]

There are USB ports that plug into 12VDC accessory outlets and drop the 12 VDC to 5 VDC for USB use. There is one in the 12VDC Accessory outlet in the Charging center I posted a pic of in post #2.

The OP mentioned a "Lap Top" computer as well. I don't know about the Mac stuff, but the only Laptop I have ever seen that would run off of 12 VDC was a little 9" net book I used to have.

Lap Tops usually require that they be powered through the 120VAC power supply. If all you have is 12 volts, there is a need for an inverter. As there is almost no other way to get there, one just has to put up with the power losses of the inverter.

[Carol H]

Originally Posted by Huck

I recently bought this. Haven't had a chance to try it yet.
PowerGen 4.2Amps / 20W Dual USB Car charger Designed for Apple and Android Devices

Huck that will work with your phone and an iPad but at only 20w its of no help with a lap top.

[Carol H]

Originally Posted by Bob Miller

Lap Tops usually require that they be powered through the 120VAC power supply. If all you have is 12 volts, there is a need for an inverter. As there is almost no other way to get there, one just has to put up with the power losses of the inverter.

I use an Apple lap top currently but used SOB in the past. I do indeed when camping off the grid need to use a small plug in inverter to charge them up.

[MCDenny]

Here's a 12v charging solution for a macbook that plugs into a 12v socket.

http://www.amazon.com/BiXPower-cigar.../dp/B00823OLUM

Don't know what in the black box but since it's taking 12v DC to a little higher DC voltage (16.5 v according to my MacBook Pro charger) it's probably not an inverter.

[Carol H]

Originally Posted by MCDenny

Don't know what in the black box but since it's taking 12v DC to a little higher DC voltage (16.5 v according to my MacBook Pro charger) it's probably not an inverter.

Hummmm I am going to suggest it is of some sort which is what the box attached to it is probable doing. Could be wrong though!

[Bob Miller]

12>>>24 volt adapter.

Actually it's difficult to kick dc voltages up at any more than minimal power levels without generating a lot of heat.

Sooo devices like this are usually small scale electronic inverters that kick the 12 DC up to about 30 volts AC inside the black box and then step that down to whats needed, run that through a AC-DC converter and, in this case, you select what you need for an output.

Bottom line is that it will consume power doing that.

[Carol Ann in TO]

http://www.mikegyver.com/Store/

This guy has been building options for charging MacBooks without AC power for years. I have a 12volt charger from him. It works well. You still need to have a source of 12volt power though. The battery will not last forever without being recharged.

As for USB charging for iPods, iPads and iPhones -- not all USB chargers are created equal. The cheap ones will manage a iPod but May not provide enough power for the more power hungry items. Ask me how I know. Actually don't.

[cpaharley2008]

Here is a good one @ Amazon Amazon.com: BESTEK usb adapter car cigarette lighter socket car splitter adapter 4 way plug socket usb outlet dc charger power adapter 12V socket 24V dc adapter car charger Ipad Dual USB charger 2.1A MRS152UV: Car Electronics $15 and you have 2 x12v outlets and one Apple USB port and one regular USB port

[Night Sailor]

I installed three of these in my camper. They are dual ports so you can charge more than one thing at a time. They do have a small electrical draw when not used. I put mine on switches to turn them off. There is a small red LED which informs you it is powered.

I believe I used a 1 1/8" hole saw and it was a wee bit tight. 1 1/4" might be better. There are two spade males on the back. The more centered one is positive and the one on the edge is negative.

Blue Sea Marine Grade Dual USB Charger Socket 1016 | eBay

These are also available with an adjoining cigarette lighter which would be better for a small inverter to charge a MacBook.

[blodn1]

Off the subject a little, but something like this could work for the application:
Amazon.com: Coleman 22007 7.5W Folding Panel: Sports & Outdoors

[frankcfx]

My MacBook requires 110 AC to run and charge the battery. Some of the small inverters my not be a good choice. Check with your Apple store for their recommendation for an inverter.

[Glenn Baglo]

Charge my MacBook Air via a cheap 200W inverter in the trailer or in the car. I haven't had any issues.
Could you elaborate why it may not be a good choice?

[Night Sailor]

I have used a cheapo inverter to charge my Macbook without any issues.

I suppose these square wave inverters of modified square wave inverters could cause interference. That has not been the case for me.

[Otters]

I bought this for my Vaio computer. Amazon.com : Pwr+ Car Charger DC Laptop Adapter Power Cord for Sony Vaio : Laptop Computer Chargers And Adapters : Computers & Accessories
Its just like the AC charger but plugs into 12v. Its worked great in keeping my computer charged as I use it for watching video in addition to the usual computer stuff. I'm sure they must have similar Mac versions. I still have a solar panel though to keep the 12v charged. Haven't had an issue even with my grandkids countless hours of video watching and games.

[frankcfx]

Well from what I see here price seems determine which inverter to buy.
Check out this site on inverters:
HowStuffWorks "Inverter Installation"

In part this is what is posted:

The output of an inverter is a very square wave, not like the smooth, round wave of a perfect sine. Some devices are inherently sensitive to the signal produced by an AC wave. Typically, these are devices that receive or broadcast some kind of signal, such as audio or video equipment, navigation devices or sensitive scientific equipment. You can see or hear the square waveform on a television as lines on the screen or a steady buzz or hum.
Cleaning up the sine wave requires a series of filters, inductors and capacitors. Inexpensive inverters have little or no filtering. The alternating current they produce has a very square wave, which is fine if you just want to make coffee or run something with a simple electric motor. If you need a smoother sine wave, you'll need an inverter with better filtering. Of course, better filtering also costs a little more. Inverters can get extremely expensive, even costing thousands of dollars, that is, if you're looking for an inverter with a smooth sine. The good news: Given a large enough budget, you can purchase an AC power inverter that produces virtually perfect AC sines. In fact, some high-end DC to AC inverters can make sine waves that are even smoother than the AC power supplied to your house.
The final specification to look for is the wave output of the inverter. If you'll be powering any of the equipment that is sensitive to square waves, look for an inverter with a "perfect sine" wave output. Be prepared for sticker shock -- a perfect sine inverter can cost almost 10 times as much as the same wattage inverter with a modified sine output. Modified sine means that the current is run through some filtering, so it isn't a square wave, but it isn't totally smooth either.

This describes the difference in inverters.
Frank

[Glenn Baglo]

Originally Posted by frankcfx

--
This describes the difference in inverters.
Frank

But, it doesn't explain why I would want to spend 10 times as much on an inverter to charge my Mac, when the cheap unit I have does the job.

baglo

[frankcfx]

There is an old saying that you get what you pay for. You pays your money and you takes your chances. Do you actually know what your putting into the Mac Power Supply. Being it is an Apple product the power transformer probably does a good job of cleaning up garbage power put into it. Try plugging a radio, DVD player or small TV into the inverter, does it buzz from dirty AC from the inverter? If not you might have a decent inverter or the equipment is cleaning it up.
Frank

[MCDenny]

True sine wave inverters are more efficient ( longer battery life) driving motors. I believe they use about 20% less power. Some applications don't make any difference. No clue whether it matters to chargers.

True sine wave inverters are 2x or 3x the cost of a square wave one. Certainly not 10x.