TACHO signal (from fan or other motor) can be connected to DI input (indication)
if using DI16 module or Combi36 module, connect DI-point connectors together.
If using DI-16-C module, connection shall be done as following:
Example EC (Electronically Controlled) fan with "TACHO" output signal.
This signal is originated from "Open collector" output on the motor electronics block and cannot be detected by normal DI input cause there is no voltage or closing contacts to measure.
S1..16 connectors has output voltage which may be used to detect "open collector" indication signal.
You need to connect S16 (S1..S16) together with 16 (1..16). Then connect to TACHO indication output.
IMPORTANT: Ground must be the electrically connected between DI-16-C and motor (fan) Ground connectors. It is recommended to check it with multimeter.
As a result, you may have PWM input signal on corresponding DI point which may be used for indication or rotation speed measurement.