The winch shown in the illustration operates in any of the positions with the master switch in the 'lower' direction, but will not 'hoist' in any of the master switch hoist speed positions. Which of the listed faults would MOST likely be the cause? Illustration EL-0102
β’ Trace the control circuit paths for hoist (H) and lower (L) coils from the UV (undervoltage) contact downward. β’ Look at how the limit switches LSL and LSH are wired and which motion each one can interrupt. β’ Notice what would happen to BOTH directions if the undervoltage relay (UV) or overload (OL) contacts opened.
β’ When the winch lowers in all lower positions, which parts of the control circuit MUST already be working correctly? β’ Which single component, if failed open, would affect only the hoist direction but leave the lower direction completely normal? β’ If the motor overload or UV contacts opened, would power still be available to either coil H or coil L? Check the common points they share.
β’ Verify which terminals go directly to the H coil versus the L coil, and which devices are in series with each. β’ Confirm whether LSL (5β6) is in the hoist or lower path, and whether LSH (9β10) is in the hoist or lower path. β’ Check whether an open at UV 1β2 or at the overload (OL) contact would remove control power from BOTH hoist and lower, or only one direction.
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