Now mount two diodes as shown here: IMG_1902.JPG Please observe the polarity of the diodes: The cathodes of the diodes should be connected to the T-junction center tap. You could use any small signal diode, like for example a 1N4148, but to prevent too much voltage drop loss across the diodes, it is ...

Below instructions to modify your ventilation unit to allow simultaneous remote and 0..10V control. First remove the circuit board. Be careful here, because the main power supply capacitor carries 400V DC , for a long time after the unit has been unplugged! You can discharge it by shorting it ...

If you use the 0-10V terminals, you MUST DISCONNECT the original RF unit. There is an explicit warning about that in the manual, so I did not try to use them in paralel. Indeed, you cannot wire two 0-10V outputs together under one 0-10V input terminal. This is due to the nature of 0-10V outputs ...