So I've been looking for a relatively inexpensive way to power my MacBook Pro in the car (Sub $50 preferrably), and I saw an inverter going for $30 on Amazon and at Wal-Mart. Are square wave inverters safe to use? Or do I risk damaging my computer?
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Power inverters, Car charging, etc.
- Thread starter Papajohn56
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The Pure Sine thing is what I'm wondering about. I know the MacBook Pro's power supply converts AC to DC, so I'm really taking these steps without pure sine:
12v DC -> 120v AC Square Wave -> 18.5v DC in power supply
I'd recommend a simple cheap ebay 70w modified sine wave inverter. The square wave ones are a bit dodgy as they emit basically a bunch of constant voltage positive and negative electrical pulses which don't approximate well to AC.
But I've found the modified sine wave ones work well enough for laptop AC adapters and are very cheap (on ebay at least).
But I've found the modified sine wave ones work well enough for laptop AC adapters and are very cheap (on ebay at least).
I have no clue why Apple has nto made car chargers. My main concern is why Apple has not sent out the design to be used for third party manufacturers to use.
Wouldn't you want to get an inverter that can put out at least 85W, since that's what the power adapter uses?
I've used a fairly cheap (modified sine, I believe) with my old ibook before, but that was a lower draw. Be sure your vehicle will be able to handle the extra pressure put on the electrical system--as long as you're not driving my old 88 Cavalier, you are probably fine.
I've used a fairly cheap (modified sine, I believe) with my old ibook before, but that was a lower draw. Be sure your vehicle will be able to handle the extra pressure put on the electrical system--as long as you're not driving my old 88 Cavalier, you are probably fine.
http://www.amazon.com/Xantrex-Techn...64-1970545?ie=UTF8&s=hi&qid=1183800396&sr=8-4
That's one I've been looking at. 175 Watts, and a USB port so I can charge my iPod at the same time. Nice
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and 175 W should be plenty--even assuming that, for a 29.99 device, that's probably a peak number--you'll be able to sustain the 85W with headroom to spare (which, in turn is a peak wattage requirement anyway?).
Nicer than mine
but that was several years ago.
Nicer than mine
but that was several years ago.and 175 W should be plenty--even assuming that, for a 29.99 device, that's probably a peak number--you'll be able to sustain the 85W with headroom to spare (which, in turn is a peak wattage requirement anyway?).
Nicer than mine
According to the manufacturer, it's 150 sustained, 175 for 2 minutes at high temps, and 250 peak. This looks like a real good one.
Bad behaviour with non-sine wave inverters
We have a bush installation (Amboseli Elephant Research Project, Amboseli National Park, Kenya) with a solar system delivering non-sine wave power through a Xantrex inverter. Only problems appear to be associated with colleagues plugging in MacBooks. The following has happened: the power supply fries (older iBook); the inverter reports a short and shuts off. Our technical guy reports similar problems Mac-associated at other installations. So question: is there something special about Apply power supplies that obviate funtioning with inverter-based (esp. non-sine wave) systems. Thx for help.
We have a bush installation (Amboseli Elephant Research Project, Amboseli National Park, Kenya) with a solar system delivering non-sine wave power through a Xantrex inverter. Only problems appear to be associated with colleagues plugging in MacBooks. The following has happened: the power supply fries (older iBook); the inverter reports a short and shuts off. Our technical guy reports similar problems Mac-associated at other installations. So question: is there something special about Apply power supplies that obviate funtioning with inverter-based (esp. non-sine wave) systems. Thx for help.