How can I find out which USB Type C port is supplying power I have a MacBook Pro 15" Late 2016 with USB-C ports. I also have a LG 27UD88 monitor that can supply 60W, and a CallDigit Dock that can supply 90 W. But still sometimes the MacBook is at 0% battery, even when working with very low CPU load.

Question: Is there a way to find out from which port the MacBook is supplied with power? 

Of course, I could measure the current on the AC side of the power supply, but I'd rather look for a software tool.
The current should be displayed in your Power settings menu.