Thanks for the answers, when looking at the same figure it looks like E+ is powered with the line in but also going through the S8850 transistor, that has a max A of 125m (http://www.datasheets360.com/pdf/-252002789868889517) and since each load cell only uses 5mA it shouldn't be a problem running 16 on it, right?
That depends on how much base current the HX711 can provide to saturate that transistor (Hfe is almost meaningless with <0.7volt across the transistor). Can't find that in the HX711 datasheet.
That transistor circuit is basically a low dropout voltage regulator, with R1,R2 providing the feedback.
The boards I know are set to 4.3volt.
You could measure E+ with one load cell, and again with 16 load cells.
It should be close to 4.3volt in both cases.