MacBook Pro Charger Question

tl01

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I left my MacBook Pro charger in my car at the dealer. I bought a nice usb-c cable for something else... can I use that to charge my computer? Say with an ipad charging block?
 

New_Mac_Smell

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No. You'll need a charger capable of delivering enough wattage to your computer (Depending on which you have). An iPad charger isn't going to cut it, if it even worked. I don't know how the handshake would work and so power delivery commence.

Also you need to check the USB-C cable to see if it's rated for the wattage. Most are cheap little things that do about 30w max. You'd want a more expensive dedicated one rated for 100w for charging.
 

tl01

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Jun 20, 2010
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No. You'll need a charger capable of delivering enough wattage to your computer (Depending on which you have). An iPad charger isn't going to cut it, if it even worked. I don't know how the handshake would work and so power delivery commence.

Also you need to check the USB-C cable to see if it's rated for the wattage. Most are cheap little things that do about 30w max. You'd want a more expensive dedicated one rated for 100w for charging.
This is just a one time charge to save driving back for my charger. I decided to try it. Will it ruin my computer? So far it has gone from 19 to 49 percent since about 30 mins after I posted.
 

New_Mac_Smell

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This is just a one time charge to save driving back for my charger. I decided to try it. Will it ruin my computer? So far it has gone from 19 to 49 percent since about 30 mins after I posted.
Using an iPad charger??

As long as the computer is powered off I mean it should charge. But I'm very surprised if it's charged 30% in 30 minutes... It won't damage anything, it's just supposed to be significantly slower or basically not charging above drain rate. Hmm.
 

tl01

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Using an iPad charger??

As long as the computer is powered off I mean it should charge. But I'm very surprised if it's charged 30% in 30 minutes... It won't damage anything, it's just supposed to be significantly slower or basically not charging above drain rate. Hmm.
The 30 percent was in about an hour and half. It was 30 mins after I posted that I started. The computer is off. I don't mind slow. I just don't really have time to run back to the dealer to get my charger. I likely have to go back for a rental car later tomorrow so I just need a day's charge from it.
 

New_Mac_Smell

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The 30 percent was in about an hour and half. It was 30 mins after I posted that I started. The computer is off. I don't mind slow. I just don't really have time to run back to the dealer to get my charger. I likely have to go back for a rental car later tomorrow so I just need a day's charge from it.
Well I guess you've found a little way of charging your computer in a crisis then. Is it a 13" nTB version by any chance? I cannot imagine this would work with a 15"!
 

tl01

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G
Well I guess you've found a little way of charging your computer in a crisis then. Is it a 13" nTB version by any chance? I cannot imagine this would work with a 15"!
It is the newest 13" touch bar. I suspect it would be harder with the 15.
 

nawoo

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Feb 3, 2008
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No. You'll need a charger capable of delivering enough wattage to your computer (Depending on which you have). An iPad charger isn't going to cut it, if it even worked. I don't know how the handshake would work and so power delivery commence.

Also you need to check the USB-C cable to see if it's rated for the wattage. Most are cheap little things that do about 30w max. You'd want a more expensive dedicated one rated for 100w for charging.

Nonsense. I left my MacBook Pro charger at home before going on a trip last weekend.

Bought a cheap usb A - usb-C cable at the airport, plugged it to my SKROSS travel adapter which has 2 USB ports, and it charged the MacBook Pro 2017 15 inch just fine.

Also charged my Xiaomi USB-C portable battery pack just fine as well
 

New_Mac_Smell

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Nonsense. I left my MacBook Pro charger at home before going on a trip last weekend.

Bought a cheap usb A - usb-C cable at the airport, plugged it to my SKROSS travel adapter which has 2 USB ports, and it charged the MacBook Pro 2017 15 inch just fine.

Also charged my Xiaomi USB-C portable battery pack just fine as well
Well tickle me pink. Are you saying I can throw out that weighty expensive power adapter that came with my MBP and use a phone charger instead?
 

nawoo

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Feb 3, 2008
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Well tickle me pink. Are you saying I can throw out that weighty expensive power adapter that came with my MBP and use a phone charger instead?
Not even a phone charger. A travel adapter with a USB port will do.

I'm currently doing an experiment now to compare the difference charge times between the MacBook Pro charger and my Skross travel adapter. Charging from 0% to 100.

Will update here
 

New_Mac_Smell

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Not even a phone charger. A travel adapter with a USB port will do.

I'm currently doing an experiment now to compare the difference charge times between the MacBook Pro charger and my Skross travel adapter. Charging from 0% to 100.

Will update here
What's the voltage/amps of that travel adapter though? Phone charger is the weakest I can think of.

Are you powered on or off, standby? You'll have to repeat tests with variables.
 

nawoo

macrumors regular
Feb 3, 2008
149
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What's the voltage/amps of that travel adapter though? Phone charger is the weakest I can think of.

Are you powered on or off, standby? You'll have to repeat tests with variables.
Ok using the Apple MacBook Pro charger, I charged my mbp 15in 2017 from 0-100% in abt 1.5 hours. It is now 96% after 1 hr 26 mins on the stopwatch.

I just started timing as soon as I plugged in the cable.

Will have to use it till it's 0% again before I can time it on my Skross adapter lol
 

throAU

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Feb 13, 2012
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Well tickle me pink. Are you saying I can throw out that weighty expensive power adapter that came with my MBP and use a phone charger instead?
If you don't mind charging when not using the machine you can probably get by with a vary small charger.

However if you want to actually gain charge when doing anything more than sitting idle reading stuff, you may need a larger capacity charger than a phone charger :D
 

PBG4 Dude

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Jul 6, 2007
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What's the voltage/amps of that travel adapter though? Phone charger is the weakest I can think of.

Are you powered on or off, standby? You'll have to repeat tests with variables.
After reading a few articles comparing Apple's chargers to the competition, I wouldn't use anything else. Do you know the iPhone power adapter contains a CPU more powerful than the one in the original 1984 Mac?
 

hallux

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Apr 25, 2012
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A USB-A port is only rated for 2.4A at 5V, or a little over 10W. Anything more and you're using a cable that does not comply to USB specs, even when the destination is a USB-C device.

I don't recall where I saw it but I saw a picture of a USB-A to USB-C cable that was used on a motorcycle to charge a phone. The cable had burned up from over-current because the phone tried to pull too much through the cable due to an incorrect "negotiation" of charge current.

Yes, the port is USB-C, yes there are cables that will allow you to plug into a USB-A port but I do NOT recommend this for charging a laptop.
 
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tl01

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Jun 20, 2010
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A USB-A port is only rated for 2.4A at 5V, or a little over 10W. Anything more and you're using a cable that does not comply to USB specs, even when the destination is a USB-C device.

I don't recall where I saw it but I saw a picture of a USB-A to USB-C cable that was used on a motorcycle to charge a phone. The cable had burned up from over-current because the phone tried to pull too much through the cable due to an incorrect "negotiation" of charge current.

Yes, the port is USB-C, yes there are cables that will allow you to plug into a USB-A port but I do NOT recommend this for charging a laptop.
This is what I was worried about but I checked in and felt the cable and the charging block frequently... The cable never got warm... and the block only got as warm as it does when charging it's intended device. I don't plan to do this frequently....but I was glad it worked last night.
 
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