Bosch Junkers Vent 2000 D

Hello,

has anyone here experience with the decentralized venting system Vent 2000 D from Bosch/Junkers?
Especially about the control interface?
I read that the control panel (CV 40 H) is connected with 12V/GND/PWM lines to the venting units.
Does anyone know the frequency of the PWM or how the direction of the ventilation is controlled? E.g. <50% duty cycle one direction and >50% duty cycle the other direction?

Thanks for any hints!

I now purchased the unit. And the venting unit itself is as simple as it gets. It just consists of an ebmpabst 4412 FGPR fan.
And the electrical connection is made directly to this fan.
Frequency according to the datasheet can be 2-5kHz.
Direction is controlled by duty cycle <50% one direction and >50% duty cycle the other direction.