Drive units feature reversible DC motors. The clutch of a drive unit is tested by placing the autopilot into Auto and then Standby. Should the drive not release and the drive unit's clutch lead be properly connected to the autopilot course computer of Evolution autopilot ACU, then the drive unit may have suffered a Clutch failure. A properly functioning drive until will engage the clutch (causes the drive to lock) when 12 VDC is present across the Clutch leads. Similarly, a properly functioning drive until will release the clutch (causes the drive disengage) when 12 VDC is not present across the Clutch leads.
Testing a drive unit's motor is a relatively simple matter involving temporary connection of the drive unit motor A and B leads to a 12 VDC power circuit and verifying movement of the ram or rudder. Connect Motor A lead to +12 VDC and Motor B lead to -12 VDC and verify movement of the drive unit's ram or rudder. If the ram or rudder moves, then reversal of the motor may instead be tested by connecting the Motor A lead to -12 VDC and the Motor B lead to +12 VDC and verifying movement in the opposite directly of the drive unit's ram or rudder.
CRAFAQ#
Testing a drive unit's motor is a relatively simple matter involving temporary connection of the drive unit motor A and B leads to a 12 VDC power circuit and verifying movement of the ram or rudder. Connect Motor A lead to +12 VDC and Motor B lead to -12 VDC and verify movement of the drive unit's ram or rudder. If the ram or rudder moves, then reversal of the motor may instead be tested by connecting the Motor A lead to -12 VDC and the Motor B lead to +12 VDC and verifying movement in the opposite directly of the drive unit's ram or rudder.
CRAFAQ#