nb Peter wrote:
I need a definitive answer.
The definitive answer is in nearly all cases you can't use anything other than powerful household current (or something similar like a portable generator) to charge and maintain the power requirements of a Mac laptop computer.
What most people do is attempt to use 12v to 110v step up transformers in their vehicles, then connect their Magsafe with it's step down transformer to 16.5 volts (or so) 65/85 watt to supply power to run the computer and/or charge the battery.
The problem is there isn't simply enough wattage at the 12v end, like in most cars with simple cigarette lighters not designed for heavy wattage needs.
If one does this on a system that doesn't have enough wattage, the best result is a slowing of the draining of the battery provided the battery was near fully charged (like via high wattage household current) earlier.
There also can cause overheating/premature death of the wires in a vehicle not designed to have such a high drain of electrons. Solving the electrical problems of a car is extremely expensive, usually all the wiring is replaced as that's still expensive but less expensive than trying to find out where the problem is in a mass of wires.
Emergency and police vehicles have beefed up wiring and power systems to power devices like computers and emergency equipment, however the typical passenger car usually isn't, unless it's a used police or emergency vehicle sold to the public.
Apple's Magsafe connector is proprietary, meaning only Apple can allow other companies to use their design which they rarely do because they can't trust other companies to maintain the proper quality to ensure no damage occurs to the Mac itself, which Apple would then have to repair under AppleCare or warranty.
The Mac also talks to the MagSafe I believe now to better ensure no other hardware hack is used, like cutting off the end of a Magsafe and wiring it to a 12v to 16.5 adapter, like a few were doing for profit.
Apple provides a Airline adapater that looks like a 12v car charger, but because airline voltage is higher like about 15v or so, it can be used to slow the drain of the battery, but again, still not enough wattage to charge the battery.
If your Mac is old, out of warranty or AppleCare, your certainly free to experiment, however if Apple could charge up/run a Mac properly in all passenger vehicles they would have included such a adapter integrated on the MagSafe itself long ago because people want to that so much.
I checked this one out a while ago. Lavolta told me it would not work with the new?? MBP retina display - I didn't know there was an old one! The key is when they talk about the new 'L' connector. As you know the retina display has the 'T' connector.
However, thanks very much for it does look as it is what I'm looking for.
Hi nb Peter,
I found this site, and this guy seem to know what he is on about.
It's a solution he manufactures himself.
He respects apple's patents by modifying existing Magsafe connectors & adapters and not using illegal 3rd party connectors.
Expensive, but when their is no other alternative....
What a load of tosh!! Everyone thinks they know everything!
Your problem is very easily solved. Your in the UK? Right. So go buy a 12 volt to
240volts inverter, they come with either the 12v plug which will run upto 150 watts
Or if you want to be really safe use the supplied direct battery leads. Wired up properly
To the cars battery it won't interfere with the vehicles wiring.
A 150 or 300 watt inverter is all you need British cars are wired upto 150 watts as standard.
( please refer to your vehicle's hand book.) through 12 v sockets
My vehicle has 3 12volt sockets. 2 in the front ( 1 is piggy backing) rated at 150 w
The other in the rear is wired to to fuse box ( By my dealer) and also rated at 150 w
My car also has a 50 amp 12 volt supply in the back running a 2500 watt inverter directly
From the vehicle. With 2 220 volts ( British standard). I run my Mac Pro very safely. My advice
Is go buy a 150 w inverter from Halfords. And use the Mac supplied power adaptor.