In the illustrated motor controller, what do the contacts across terminals "3" and "4" of the control circuit represent? Illustration EL-0017

Correct Answer: Option B — normally-closed overload relay contact

Thermal overload protection in marine motor controllers uses normally-closed contacts connected in series with the holding coil control circuit. When excessive current heats the bimetallic elements, these contacts open, de-energizing the main contactor coil to protect motor windings from sustained thermal overloads.