1grouchy
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Q: Can MagSafe 2 difference in output voltage result with any hardware damage on MBP?

Magsafe 2 85W have output voltage of 20V.

 

On the other hand my MBP (Late2012, 13'' Retina) says Rate = 16.5V max.

 

I read thru the forum that this MagSafe 2 85W can be used on MBP 13'' Retina machines, I didn't try it yet because I know that difference in voltage can hurt some other PCs.

 

I presume that Apple would never do two adapters with the same jack who can hurt MB machine with that jack, and I know for official Apple power adapters page (MagSafe power adapters) where they mentioning that higher wattage can be used:

 

"You can use a compatible higher wattage adapter without issue, but it won't make your computer charge faster or operate differently. Lower wattage adapters will not provide enough power."

 

So, what I would like is some logical explanation for how this difference in voltage is covered by Apple, not to hurt lower voltage rate MBPs?

 

P.S. I've googled yesterday all day and I haven't found any answer on this, so I think that this anwer can be usefull answer for some other people in the future who are interested in the same question.

MacBook Pro, OS X Yosemite (10.10.3), MBP Retina Late2012

Posted on Jun 24, 2015 11:35 PM

by spudnuty,Solvedanswer
spudnuty spudnuty
Level 5 (7,097 points)
Mac OS X
A:

" is some logical explanation for how this difference in voltage is covered by Apple, not to hurt lower voltage rate MBPs?"

So that would be a question of input voltage tolerance. If you look at the AC input voltage tolerance on a 60 W adapter the tolerance is 100 - 240 VAC. That's a huge difference in voltage but the output is always going to be 16.5 Volts because of circuits in the power adapter that regulate the output.

So in general the difference in the output voltage probably wouldn't be an issue.

The big issue would be if you can find a MagSafe 2 to MagSafe 1 adapter. I haven't seen one yet.

http://forums.macrumors.com/threads/magsafe2-to-magsafe-adapter-the-other-way-ar ound.1424782/

Not sure on the date of this one:

http://www.everymac.com/systems/apple/macbook_pro/macbook-pro-retina-display-faq /macbook-pro-retina-display-magsafe-2-se…

"There is not a MagSafe 2-to-MagSafe adapter, so it is not possible to use a newer MagSafe 2 power adapter with an older MacBook that supports the original MagSafe standard."


So the question of whether the older MBP could handle the higher MagSafe 2 voltage is basically mute since there's no adapter to do that AFAIK.

However I would say that the approximately 20% deviation in voltage while high could probably be handled by the MBPs input circuit.

After all Apple makes an adapter to go from MagSafe 1 to MagSafe 2 so that's the same amount of deviation.

Posted on Jun 25, 2015 1:41 AM

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1grouchy

Q: Can MagSafe 2 difference in output voltage result with any hardware damage on MBP?

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  • by kaz-k,

    kaz-k kaz-k Jun 25, 2015 12:22 AM in response to 1grouchy
    Level 5 (5,828 points)
    Desktops
    Jun 25, 2015 12:22 AM in response to 1grouchy

    Your charger is 60W magsafe2 adapter.

  • by 1grouchy,

    1grouchy 1grouchy Jun 25, 2015 12:31 AM in response to kaz-k
    Level 1 (0 points)
    Jun 25, 2015 12:31 AM in response to kaz-k

    kaz-k wrote:

     

    Your charger is 60W magsafe2 adapter.

     

    That's far away from answer to my question. I knew that, my old 60W power adapter died a few days ago and I received 85W MagSafe 2.

     

    Thanks anyway.

  • by spudnuty,Solvedanswer

    spudnuty spudnuty Jun 25, 2015 1:41 AM in response to 1grouchy
    Level 5 (7,097 points)
    Mac OS X
    Jun 25, 2015 1:41 AM in response to 1grouchy

    " is some logical explanation for how this difference in voltage is covered by Apple, not to hurt lower voltage rate MBPs?"

    So that would be a question of input voltage tolerance. If you look at the AC input voltage tolerance on a 60 W adapter the tolerance is 100 - 240 VAC. That's a huge difference in voltage but the output is always going to be 16.5 Volts because of circuits in the power adapter that regulate the output.

    So in general the difference in the output voltage probably wouldn't be an issue.

    The big issue would be if you can find a MagSafe 2 to MagSafe 1 adapter. I haven't seen one yet.

    http://forums.macrumors.com/threads/magsafe2-to-magsafe-adapter-the-other-way-ar ound.1424782/

    Not sure on the date of this one:

    http://www.everymac.com/systems/apple/macbook_pro/macbook-pro-retina-display-faq /macbook-pro-retina-display-magsafe-2-se…

    "There is not a MagSafe 2-to-MagSafe adapter, so it is not possible to use a newer MagSafe 2 power adapter with an older MacBook that supports the original MagSafe standard."


    So the question of whether the older MBP could handle the higher MagSafe 2 voltage is basically mute since there's no adapter to do that AFAIK.

    However I would say that the approximately 20% deviation in voltage while high could probably be handled by the MBPs input circuit.

    After all Apple makes an adapter to go from MagSafe 1 to MagSafe 2 so that's the same amount of deviation.

  • by 1grouchy,

    1grouchy 1grouchy Jun 27, 2015 7:46 AM in response to spudnuty
    Level 1 (0 points)
    Jun 27, 2015 7:46 AM in response to spudnuty

    Thank you for taking time to investigate and answer my question spudnuty.

     

    You've made a good points above.

     

    Anyway, I've started to use my new 85W charger yesterday. I tracked DC input voltage on macbook and it's between 16.2V and 16.5V so that seems fine.

     

    Until now there were no side effects. I hope that it will stay like that.

     

    I hope that Macbook will tolerate this difference in voltage well without electronic circuits to suffer.

  • by spudnuty,

    spudnuty spudnuty Jun 27, 2015 2:38 PM in response to 1grouchy
    Level 5 (7,097 points)
    Mac OS X
    Jun 27, 2015 2:38 PM in response to 1grouchy

    So in that link you posted:

    Find the right power adapter and cord for your Mac notebook - Apple Support

    notes the:

    "MacBook Pro (Retina, Mid 2012)"

    as being compatible w/ the 85 W MagSafe 2.

    "I tracked DC input voltage on macbook and it's between 16.2V and 16.5V so that seems fine."

    So it that internally? Apparently the regulator pulls the voltage down to the correct voltage.

    Glad it worked out.

    Thanks for the check mark.