Wireless charging of iPhone XR

[RejZoR]

I got myself this Qi charger:

http://baseus.com/product-284?lang=en-us

 

Interesting thing is that when I plug it to my USB charger that has 2.4A 5V output, it only charges the iPhone at 5W even though it should be capable of doing it at max 7.5W and up to 12W on non iPhone devices since it has the amperage to drive up to 12W even. However, if I plug it to the QC3.0 port, Qi charger runs at 9V and per its display, charges iPhone at 8+ W. Now I'm confused since I thought it should go up to 7.5W max on 5V port and I am kinda afraid to use it with QC3.0 port since I have no clue how XR charges. It seemed to charge in 9V mode too, but since I couldn't find any specs I don't want to fry anything lol even though I'm assuming phone and charger should recognize each other properly in this regard so it shouldn't happen. Can't find any exact detailed specs for iphone XR and it's wireless charging other than "it has one and can be done at max 7.5W".

[DrMacintosh]

7.5W is the max that iPhones are rated for. Any higher is going out of spec according to Apple. 

https://support.apple.com/en-us/HT208078

 

Doesn't mean it won't charge with a higher wattage, its just not designed to be used that way. 

[RejZoR]

Yeah, but why it doesn't charge at 7.5W at 5V when it's plugged to a 5V USB charger ?