I have been building a new controller unit for a ~20 years old gate opener because it was never reliable, and eventually stopped working entirely.
So far, I have got everything working except from stopping the motors at the correct time. The motor has 5 wires, two for 24VDC for powering the motor, two 12VDC for powering a "pulse generator", and a single "pulse generator" wire.
I was not able to figure out what kind of signal this pulse generator delivers, so I started off by just starting the motor, waiting for some time and then stopping it. However, I realized that this desynchronizes really quickly which results in the gate hitting the wall or not closing correctly.
So I tried analyzing the signal from the pulse generator, because the old board could do this starting and stopping precisely. It is a 10 kHz squarewave signal, but no matter how hard I tried stopping the motor, it never changed in frequency or duty cycle, but that may be due to my 30€ oscilloscope from ebay. I also observed that the original board would refuse to boot if the pulse cable was disconnected. When the cable was removed while the motor was moving, the motor more or less stopped.
Has anybody had experience with such circuits / signals?
If it helps, I have got the users manual of the original controller ("Einhell FA-G 2601").
The owners manual can be found here.