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If you bought an extra MBA charger, did you buy the 45W, 60W, or 85W?

Which extra MagSafe adapter for your MBA did you actually buy?

  • 45W

    Votes: 15 55.6%

  • 60W or 85W

    Votes: 12 44.4%
  • Total voters
    27
V

VMMan

macrumors 6502a
Original poster
Mar 29, 2009
766
239
I would like to have an extra charger/adapter for my MBA, and realize that most forum members write that using a higher rated charger/adapter (i.e. 60W or 85W) is supposed to be fine.

The cost is about the same for the 45W, 60W, and 85W Apple MagSafe charger/adapters. The 45W is a little smaller, but they're not that different from each other in terms of size either.

My question is for those who actually did have to buy another charger/adapter, if you went out and bought the 45W charger, which would be good ONLY for the MBAs,

OR

if you purchased a 60W or 85W charger/adapter which in theory should be good for charging MacBook Pros in addition to the MBA.
 
i would get another 85W adapter. This way I can also use it as a spare for my 17" Pro. In fact, I'm trying to see if I can have an 85W adapter plugged into every room in my house, so I can basically have a Mac charging station in any room with no regard to a Pro or Air.
 
I heard using a higher wattage power cord could damage the battery and not make it last as long. I'm skeptic though and couldn't verify that. I'd be interested to know if this is true.
 
45W. Only because the brick is smaller and portability is the reason we purchase a MacBook Air.
 
AppleTech22 said:
He is not asking which one will work, they all will.
Click to expand...
technopimp said:
I don't think he was asking which adapter would work with the Air,
Click to expand...
This is exactly why I posted the link that I did. Inevitably, questions like this would pop up:
pgiguere1 said:
I heard using a higher wattage power cord could damage the battery and not make it last as long. I'm skeptic though and couldn't verify that. I'd be interested to know if this is true.
Click to expand...
If you read the link, you'll see:
Power adapters for Intel-based Apple portables are available in 45W, 60W, and 85W varieties. Although you should always use the proper wattage adapter for your Apple portable, you can use an adapter of a higher wattage without issue.
Click to expand...
 
85 is under my desk at my office, it will charge anything that comes by, tue 45 that came with my MBA is the one that travels when needed. Light, small and powerful enough. Advantage is also that the 85w's don't get that warm when you are using the MBA to the maximum and charging the battery at the same time.
 
GGJstudios said:
This is exactly why I posted the link that I did. Inevitably, questions like this would pop up:

If you read the link, you'll see:
Click to expand...

That doesn't make sense though. Why would they say "You should ALWAYS do X, but if you do Y it will not make any difference"?

I'm trying to find the link on their site I saw before, but it basically said using a higher wattage was perfectly acceptable, but using a lower one was NOT recommended.
 
I have an 85, 2x 65, and the 45.

I am debating whether I want to keep one of each or get rid of the 85, but one has to go with another machine...

Thinking of keeping the 85 for potential MBP purchase in the future.
 
I'm using the extra 45W I had for my previous 11" Air (still in my sig line, oops, gotta change that) with my new 13". I like it for the small footprint/portability.
 
Lets think about this guys

pgiguere1 said:
I heard using a higher wattage power cord could damage the battery and not make it last as long. I'm skeptic though and couldn't verify that. I'd be interested to know if this is true.
Click to expand...

The Apple Display for sale has the MagSafe adapter which supports charging of all MagSafe Macs.

That has got to be 85W to support the biggest laptops.

But Apple say its compatible with all laptops, including the Airs.

Therefore, just buy the 85W incase you one day decide to get a bigger Mac.

F
 
A lot of the answers here are completely missing the point here... It's not a matter of what will work. It's a matter of what effects (if any) there are of using an under-powered or over-powered charger. So far we (sadly) don't seem to have the answer.
 
My understanding is that power is drawn from the adapter by the device connected to it. So as long as the device doesn't try to draw more than the adapter can give, then all is good.

Therefore as stated previously an MBA can safely use any of the MagSafe power supplies and all will be fine. However, if you were to try and run a MBP 17" from a 45W adapter it will either not work at all, or will only be able to power the laptop, and not re-charge at the same time.

The same goes for using iPad adapters with iPhone or iPods - this works fine, but I doubt an iPad can charge from an iPhone adaptor.
 
dolphinhouse said:
My understanding is that power is drawn from the adapter by the device connected to it. So as long as the device doesn't try to draw more than the adapter can give, then all is good.

Therefore as stated previously an MBA can safely use any of the MagSafe power supplies and all will be fine. However, if you were to try and run a MBP 17" from a 45W adapter it will either not work at all, or will only be able to power the laptop, and not re-charge at the same time.
Click to expand...

And if you overdrive the 45W with an 85W MBP, it might catch fire. So, overall, not great. But the air doesn't always draw 45W - mine's only drawing 9.47W at the moment according to iStat menus, so whether the adaptor is 45 or 60 or 85W is largely a moot point. the only potential problem I could see is that the 60W I'm using at the moment is supplying 17.04V (btw, the brick says 16.5V on it), and the 45W supplies 14V-ish, rated for 14.5 or 15.5V - I forget which.

But therefore, the MBA must have some kind of voltage convertor built into it - after all, the electronics run at 5 and 12V, if I remember my electronics correctly. So that just leaves the battery, which is running at at 8.27V/0.20A on the 60W, and (if I just grab the 45W out of my bag...) 8.23V/0.20A from the 45W. So, I don't think I'll be worrying about it.
 
Yumunum said:
A lot of the answers here are completely missing the point here... It's not a matter of what will work. It's a matter of what effects (if any) there are of using an under-powered or over-powered charger. So far we (sadly) don't seem to have the answer.
Click to expand...

Yes, we do. Using a higher wattage charger will not harm a MacBook comes with a lower powered one.

Apple's display port monitor and thunderbolt monitor both include 85W chargers and are specifically targeted to all MacBooks, even the Airs and 13" units which use 60W chargers (I think the base 15" does as well).

Apple's own documentation says that a higher one will work as well, but not to use a lower rated one on a laptop that requires a higher one.

For what it's worth, I bought an extra 60W unit since my wife and kids use 13" MacBooks/MacBook Pros.
 
Yumunum said:
A lot of the answers here are completely missing the point here... It's not a matter of what will work. It's a matter of what effects (if any) there are of using an under-powered or over-powered charger. So far we (sadly) don't seem to have the answer.
Click to expand...

This is the main motivation behind my starting this thread.

I realize that maybe one can get away with using an 85W adapter with the MBA, but what would be ideal in terms of minimizing any risk of overload or even minimizing "wear and tear" on any transforming/converting circuitry.

If the 45W adapter is safer to the equipment then I think it's worth getting that over the more flexible 85W adapter.

But if truly, there really is no significant difference in terms of preserving one's equipment between the 45W and 85W adapters, well, I would rather buy the 85W adapter.

I don't know if anybody outside of Apple knows the answer, but I wanted to see how all of you voted with your pocketbooks in choosing an adapter.
 
Lots of people know the answer and they have posted already. You just don't seem to believe them. I'll post it again, perhaps that will make the differnce. It does not matter what you use. Both the laptops and the adapters have smart designs that will only the provide the voltage and current needed and capable of being supplied.

It doesn't matter.

At all.

Honest.
 
Yumunum said:
A lot of the answers here are completely missing the point here... It's not a matter of what will work. It's a matter of what effects (if any) there are of using an under-powered or over-powered charger. So far we (sadly) don't seem to have the answer.
Click to expand...

Apple provided the answer for using higher powered chargers. There is an internal switch. It's fine.
 
I have a couple of older 65 & 85W chargers. I only use those in fixed locations (ex: at a desk).

For anything portable, I like the smallest possible. My wife and I each have an extra 45W. One is for use around the house... and the second stays in our laptop bags so we always have it with us when we travel.

I would be shocked at myself if I ever bought another laptop larger than a MBA.

/Jim
 
pgiguere1 said:
I heard using a higher wattage power cord could damage the battery and not make it last as long. I'm skeptic though and couldn't verify that. I'd be interested to know if this is true.
Click to expand...

Which is why GGJstudios post/link to the support document was a valid contribution!
 
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