Are MBP and MBA Power Adapters Interchangeable?

Hi all,

I have a mid-2011 MBA and a late-2011 MBP. MBA came with a 45W MagSafe Power Adapter, while MBP has a 85W one.

Question: Can I use those adapters interchangeably, i.e., can I charge MBA with the 85W adapter, and the MBP with the 45W, or could that damage the computers?

 

You can use the 85W magsafe for both, but you cannot use the 45W magsafe for the MBP, as it's too weak and will most likely run hot because it's trying to charge the battery at a normal rate but cannot keep up.


Some will say that it doesn't hurt to use a lower watt charger on a system that requires more, but i am one of those that would say it would damage the charger as it's simply too weak. Having to much "watts" is never a bad thing though, it will only charge the battery up faster.

 

I never wanted to find out by frying my 11 inch air so I always kept them separate. if you can thats cool i guess. i still wouldnt mix and match though

 

I agree; I dont mix and match my chargers

 

This does sound about right if we assume that both adapters run on the same voltage. I think I have overheard a genius tell a customer that a higher watt adapter would be fine on a macbook, but I think a genius at apple store would be the best person to answer this question.

 

Both run at the same voltage, so it's 100% ok to use the 85 watt adapter with the Air. The 45 watt adapter obviously is too weak to run the MBP, but if the MBP is off, it has plenty of wattage to charge up the battery,

 

They do run same voltage. Otherwise we would see many complaining customers that doesn't know better and just plug it in no matter what wattage as they both use magsafe.

I have made my own chargers for many laptops and i can say for sure, i don't need to be an "apple genius" to answer that. I've been modding computers for 13years now, every little part of it Just saying!

And i've also tested the lower wattage type on a laptop that requires more, and sure, it works fine until the charger overheats (if you load the computer a lot running 100% cpu etc which equals higher consumption) then that's gonna happen. Otherwise you can if you want run a lower wattage supply too, but then you need to know if's and what's, so that's why i don't recommend doing the other way around. With the computer off though, there is not gonna be a problem charging no matter what wattage, it's just gonna take longer.

Note, a lower wattage charger isn't gonna hurt your mac, the charger is what's gonna get hurt by overheating, IF it overheats, the risk is not that big, you can easily find out by testing it yourself and feel if the magsafe adapter gets hot. Like burning hot.


Unlike others, i never answer a question that i don't know the answer too without saying that i am uncertain, in this case, i'm 100% sure.

I just wanna put that out there, if anyone cares about that.
My time on forums and helping people started back in 2000, so i got plenty of experience helping people, and i like doing that too, as it's always grateful to get a thanks and make someone else happy!

True!

 

Exactly right.


Macbook Air can use either. Mbp only use mbp charger.

 

Thanks everyone for providing valuable input. I really appreciate your time.