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JoA59

Q: are the apple airbook ports powered while asleep

My new macbook air lost 46% of its power overnight while asleep.  I had a usb hard drive conected to it but assumed it would sleep also.  However, perhaps I was wrong.  Does the usb port stay powered while the computer is in sleep mode?

 

Thank you,

MacBook Air, OS X Yosemite (10.10.3)

Posted on May 3, 2015 8:01 AM

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Q: are the apple airbook ports powered while asleep

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  • by FoxFifth,Apple recommended

    FoxFifth FoxFifth May 3, 2015 8:46 AM in response to JoA59
    Level 7 (25,966 points)
    iPhone
    May 3, 2015 8:46 AM in response to JoA59

    The ports are powered while the computer is in sleep mode. I rarely have an external drive connected but just checked and it does stop spinning within a minute or so after the computer is put into sleep mode.

  • by JoA59,

    JoA59 JoA59 May 3, 2015 9:08 AM in response to FoxFifth
    Level 1 (5 points)
    May 3, 2015 9:08 AM in response to FoxFifth

    Thank you.  What would explain such a large use of power if the harddrive does not spin after a couple minutes?  The power was at 61% when I put the computer to sleep at 10:05 AM and was at 15% the next morning.  (I've been trying to keep track to see what I can safely leave connected and if I should shutdown rather than sleep when I'm not using the computer for a while.) I've always had a computer that had a removable battery before getting the airbook.

  • by FoxFifth,Apple recommended

    FoxFifth FoxFifth May 3, 2015 9:29 AM in response to JoA59
    Level 7 (25,966 points)
    iPhone
    May 3, 2015 9:29 AM in response to JoA59

    One thing to check: Apple menu > System Preferences > Energy Saver > Battery > Put Hard Disks to Sleep when possible.

     

    Other than that, I'm not sure. This isn't an area where I have any expertise and little personal experience. One possibility is that various drives may have different features and may have different sleep settings. I would try it a couple of nights with the drive disconnected and a couple with it connected and see what the difference in the battery is.

     

    I rarely shut down my MacBook Air -- maybe once a month on average. I usually charge it in the evening, disconnect the power, close the lid and it will be at the same percentage in the morning as it is the night before.

     

    Also, while the battery isn't removable by the user, it can be replaced for $129. My Air is 3 years old and the battery is still in good shape.

  • by JoA59,

    JoA59 JoA59 May 3, 2015 9:41 AM in response to FoxFifth
    Level 1 (5 points)
    May 3, 2015 9:41 AM in response to FoxFifth

    Thanks, again.  I'll do as you suggest and see the results.  Do you now if it is generally better to use the laptop on battery or use it plugged in when available as far as keeping the battery usable for the longest time (in years)?  I've seen both suggested as better and just don't know what to do.

  • by FoxFifth,Apple recommended

    FoxFifth FoxFifth May 3, 2015 9:59 AM in response to JoA59
    Level 7 (25,966 points)
    iPhone
    May 3, 2015 9:59 AM in response to JoA59

    It shouldn't be plugged in 100% of the time and it shouldn't be frequently discharged to a very low level. Apple used to have a support page that recommended that the battery be used a minimum of one cycle per month; examples of one cycle would be to discharge it to roughly 50% twice during the month or to 75% four time or some other combination that added up to roughly 100% usage. Again, that was the minimum recommended usage.

     

    I use mine plugged in if convenient to do so and on battery when not convenient. It has a maximum cycle count of 1,000 per the following: Mac notebooks: Determining battery cycle count - Apple Support

  • by JoA59,

    JoA59 JoA59 May 3, 2015 10:14 AM in response to FoxFifth
    Level 1 (5 points)
    May 3, 2015 10:14 AM in response to FoxFifth

    My report is rather strange.  I've just recharged and the battery light is green.  However, the report says that it is charging and that the battery is not fully charged.  The icon at the top right says 100% charge.  The report states the full charge capacity of 7503 and says it is now 7397.   So what is correct and do you think this represents a problem with either the battery or the charging system.  I'm on cycle count 6.

     

    Thanks again  You have been very helpful to a new user.

  • by FoxFifth,

    FoxFifth FoxFifth May 3, 2015 10:37 AM in response to JoA59
    Level 7 (25,966 points)
    iPhone
    May 3, 2015 10:37 AM in response to JoA59

    I would go to About This Mac and access the report again. I have seen a minor lag in that report if accessed immediately after a change in charging status.

  • by John Galt,

    John Galt John Galt May 3, 2015 10:50 AM in response to JoA59
    Level 8 (48,715 points)
    Mac OS X
    May 3, 2015 10:50 AM in response to JoA59

    The USB ports are still powered in sleep mode. Leaving any USB-powered device connected will certainly draw some power, even if it's a hard disk that stops rotating.


    That and everything else you're experiencing is normal. It's a good idea to unmount and disconnect hard disk drives when you put your MBA to sleep. Or, just shut it down. Booting a MBA takes all of 15 - 20 seconds or so.