Questions & Answers for Apple 45W MagSafe Power Adaptor for MacBook Air

From Macworld Mag 2006:

If you hold the two power supplies side by side, you’ll notice that the MacBook Pro’s is larger. That’s because the MacBook Pro uses an 85-watt power supply, while the MacBook uses a 60-watt power supply. Apple says you can use the more powerful, 85-watt power supply with a MacBook without any problems, and that in 80 percent to 90 percent of situations, you can use the MacBook’s power supply with the more-demanding MacBook Pro as well. If you’re really taxing the MacBook Pro’s processor with some heavy-duty work, the MacBook’s adapter will still be able to power the MacBook Pro—but it may not have any power left over to charge its battery.

so, yes, contrary to what everyone else has said, you can.

• Answered by Wendy S from Montgomery Village
• Nov 25, 2009
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2009 model originally used power adapter with model number A1184(60W), so electrically, this new A1344 should work. Here is the catch, if you update your mac in the following year, current 15 inch model requires charger with 85W power, so you will end up with a unusable A1344. On the other hand, 85W charger can be safely used with both old and new 15 inch model(old one will only drain 60W from it) So it will be a good back up even if you update the machine. The only down side is its slightly heavier weight and larger size.

• Answered by Jingsheng L from Baltimore
• Jan 14, 2012
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STANDARD MAINTENANCE:
For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Apple does not recommend leaving your portable plugged in all the time. An ideal use would be a commuter who uses her notebook on the train, then plugs it in at the office to charge. This keeps the battery juices flowing. If on the other hand, you use a desktop computer at work, and save a notebook for infrequent travel, Apple recommends charging and discharging its battery at least once per month.

LONG-TERM STORAGE:
If you don’t plan on using your notebook for more than six months, Apple recommends that you store the battery with a 50% charge. If you store a battery when it’s fully discharged, it could fall into a deep discharge state, which renders it incapable of holding any charge. Conversely, if you store it fully charged for an extended period of time, the battery may experience some loss of battery capacity, meaning it will have a shorter life. Be sure to store your notebook and battery at the proper temperature.

• Answered by Gary S from Jacksonville Beach
• Oct 2, 2011
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Yes it is, because the adapter was designed to work from 100 - 240 V.

• Answered by Fredy G from Jakarta Barat
• Mar 15, 2012
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no the computer knows how much power to use it will be fine

• Answered by Cameron B from West Plains
• Jul 7, 2010
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It depends on what type of applications you are running at the time, such as Final Cut Pro or Safari.

When your computer is running big applications such as Final Cut Pro, you will notice your computer will need more power to do more tasks and therefor your MagSafe power adapter may get warm/hot.

If you are using a less mighty application such as Safari, your MagSafe power adapter should NOT get hot. If it does get hot/burning; I would replace it, especially if it has been mistreated before.

Hope this helps.

• Answered by Matthew S from Prince George
• Jan 22, 2012
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The Apple 85W is capable of both 16.5V and 18.5V output (adjusts automatically to demand). So it can replace the 60W 16.5V.

• Answered by B H from Auckland
• Apr 28, 2010
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