Presuming that you wiring is correct the terminals for external speed control are com 10v and AIN. Speed control would normally be via a potentiometer. The winding of the pot would be across COM and 10v and the wiper would input to AIN. You also need to set SW2 to either 0-10v which would be normal for a pot or to 0-20mA setting. Look like parameter 1-06 should be set to 0002 for external speed control setting.