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levmc

macrumors 6502a
Original poster
Jan 18, 2019
687
25
The one I have now is 45w. I guess it's smaller so it's lighter, but if I got the 85w one would it charge much faster?
 

DeltaMac

macrumors G5
Jul 30, 2003
13,762
4,587
Delaware
45W is meant for a MBAir.
13-inch MBPro comes with 60W
Your 15-inch MBPro will work best with 85W.
The 45W, with hardly more than 1/2 of suggested power available, charging will naturally be slower.
You can expect that the 85W will charge noticeably faster
 
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levmc

macrumors 6502a
Original poster
Jan 18, 2019
687
25
I see. I didn't have much complaint with the charging speed of the 45w, but I didn't measure how long it takes. I guess I'm never in a situation where I'm in a hurry to charge it fast.

Does anyone know what the charging time difference would be?
 

DeltaMac

macrumors G5
Jul 30, 2003
13,762
4,587
Delaware
The 85 watt will charge your MBPro "faster".
Exact time is much dependent on what the initial charge is when charging starts.
Also, the 85 watt won't get as hot as your 45 watt certainly does, as it has the extra headroom that the 45 watt can't provide for charging your 95 Watt-Hour battery. (The MBair that your 45 watt charger is designed for, has a 54 watt-hour battery, or less
 
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levmc

macrumors 6502a
Original poster
Jan 18, 2019
687
25
Could the 45w make your MacBook Pro hotter too? Or just the charging cable itself will be hotter?
 

EugW

macrumors G5
Jun 18, 2017
14,935
12,906
The MagSafe adapter is a great little thing, but it's also very easy to lose.
 

DeltaMac

macrumors G5
Jul 30, 2003
13,762
4,587
Delaware
Could the 45w make your MacBook Pro hotter too? Or just the charging cable itself will be hotter?
Not likely that the MBPro will be hotter, nor the cable. The 45-watt adapter will be hotter than normal, as it is generally going to be operating at max current for that 45-watt adapter. The charge will take a longer time, too.
To state this another way - the 45-watt is not the correct adapter for any MBPro -- it's output power is too small.
Will it work to charge a MBPro? Yes, of course. (but will take longer to charge than an adapter with a higher power rating)
Is it the best match to use long term with a MBPro? no...
 
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