Our setup:
230 VAC/28 VDC converter -> 28 VDC battery -> Motor controller (28 VDC 15.6 kHz PWM) -> PCB (DC PWM to EC) -> EC motor
PCB has two wires (+/-) going in and four going out (GND, direction, supply and speed).
Motor is inside a drum which is moving a load back and forth (with the help...