In order to wire up the three-way switch for the extractor, I had to reverse engineer the contacts and the manual was both in Chinese and also applied to several different models and it was not clear which one I had purchased.
There are 12 contacts in total and I guessed that they might work as 2 sets of 3 contacts. Using the continuity mode on the multimeter, I checked how these were connected in each of the three switch positions. The top three connections only connected in the “man” position. The bottom three connections only connected in the “auto” position. So to connect up my fan so that it would come on all the time for manual and triggered from the light in auto the following wiring is necessary. As mentioned in the previous articles it might be good to have the “auto” mode triggered by something else such as a humidity detector.