Looking at the USB PD spec 1.0 PD_1.0_Introduction.pdf You can see that there are 'profiles' associated with PD. The Presentaiton is a bit out of date now.
After looking at the USB Developer docs (very dry reading let me tell you) www.usb.org/developers/docs/ Section 10 of the USB 3.0 spec on Power Delivery incase anyone wants a headache.
Best i can determine there are 3 types of usb-c PD capable supplies...
1) Fixed voltage supplies (currently most of the market share) 5v, 9v, 15v, 20v at perscribed ampages
2) Fixed voltages supplies with optional voltages such as 19.5v (suspect very rare and bundled with devices)
3) Programmable voltage supplies, capable of incremental voltage steps that can allow voltages with a minamum and maximum range like max20v min3v (currently no market share or else imporperly advertised)
So without having the official acer usb-c charger in my paws i can only conclude its most likely a number 2, though possibly a number 3.
Again if anyone spots an adapter that works with the swift3, speak up! we need adapters!
