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I plugged in my 12" MacBook charger into my 15" MacBook Pro, is this a problem?
- Thread starter Hieveryone
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I heard somewhere you can plug in a MacBook Pro charger into a MacBook but don't plug in a MacBook charger into a MacBook Pro. Not sure if this is true.
This is the 12" MacBook and a 15" MacBook Pro
What @LogicalApex said.
Macbook is a 30w charger, 13" MBP is 60w, so, all you did was trickle charge the Pro.
ADD: 15" MBP is 87w(?).
Macbook is a 30w charger, 13" MBP is 60w, so, all you did was trickle charge the Pro.
ADD: 15" MBP is 87w(?).
You fine. But don't expect the 15" to charge very fast. If you are doing much on the system it may just slow the battery drain.
So instead of just saying whether it did anything or not, which enough people have already done (it didn't), let's look at how power works for a moment.
Wattage is a function of voltage and current. Send too much of either and you can damage equipment permanently. The extreme example of this is a lightning strike.
Send too little and, well, it sort of depends but in a design like a Mac with a battery and a power management chip capable of load balancing between charge port and battery, what happens is just that the battery will charge super slowly, or maybe even drain still, but just drain slower.
There's a standard for negotiating power needs over USB, the USB Power Delivery protocol. This allows a device to tell a charger exactly what voltage and current it would like, and if the charger can, it'll deliver it. This means that even plugging an 87W charger that properly supports this protocol into your 12" MacBook won't damage it. The MacBook will communicate safe tolerances for current and voltage to the charger and only receive what it can handle.
Slow charging of lithium-ion batteries can decrease heat and improve longevity of the battery. Thus, charging with lower wattage chargers than the max spec of the device can actually be beneficial to its lifespan, as long as it's enough that you don't just drain it slowly. That said, the difference is often minor enough that the inconvenience of the speedier charge isn't necessarily worth it.
This however is the basis for the iOS 13 feature, optimised charging. This feature decreases the requested power delivery for most of the charge, and charges only to 80 until you're about to unplug the device (using machine learning to learn your daily routines), then charging to 100%. That last point is because Li-Ion batteries, for longevity, prefer sitting at 50-80% over 100%. 0% really not being so good for them
Yes, it works. Just would take an extra-long time to fully charge, and may not fully charge if you use your MBPro while you are charging.
You may also refer to the pretty good info in post #8 above, which also answers your question (should you choose to accept the answer
)
You may also refer to the pretty good info in post #8 above, which also answers your question (should you choose to accept the answer
)I use a 30W Anker GaN charger with power delivery for my MacBook. Seems fine enough and charges fast enough for my usage. I was monitoring how much power my system was drawing with a few tools like the intel power tools and coconut battery. Even while playing games like Oxygen Not Included the system was only drawing like 22W roughly.
Nice, but OP has 15" MacBook with dGPU, capable of much higher performance and much higher power consumption, especially while gaming. His machine can use 80 watts under a heavy load and recharging the battery.
I remember reading the on Apple support pages too; I think the only reason they said that is because the MB charger can't power the MBP under load, so you'll still deplete your battery if you're causing it to draw over 30W while using it.