The AC winch hoist controller shown in the illustration has a burned out hoist contactor coil that must be replaced. Before replacing the coil, the cause for the burnout must be determined. Which of the following statements represents the possible cause? Illustrations EL-0102

Question

Accepted Answer

The coil burnout may occur with a normal voltage applied to the coil (between 85% and 110% of rated voltage) if accumulated dirt prevents proper seating of the armature to the magnet.

Answer

The coil burnout may be caused by insufficient voltage applied to the coil (below 85% of rated voltage); however, excessive voltage applied to the coil (above 110% of rated voltage) will not cause a burnout.

Answer

The coil burnout may be caused by excessive voltage applied to the coil (above 110% of rated voltage); however, insufficient voltage applied to the coil (below 85% of rated voltage) will not cause a burnout.

Answer

The coil burnout may occur with a normal voltage applied to the coil (between 85% and 110% of rated voltage) if the armature is allowed to seat against the magnet with no air gap.