Elevator Mechanic Practice Exam

On a Ward-Leonard circuit the break is set, but the motor is trying to slip through the break. What is the issue?

1. Brake coil failure

2. Misalignment of the motor

3. Overloaded circuit

4. Suicide Circuit

The correct answer is: Brake coil failure

The situation described involves a Ward-Leonard circuit, where the motor is attempting to slip through the brake. The correct answer highlights that a brake coil failure is the issue. This malfunction can prevent the braking system from applying the necessary force to keep the motor stationary. In a properly functioning brake system, the coil generates a magnetic field that keeps the brake engaged. If the coil fails, the magnetic field may not be strong enough to hold the brake effectively, resulting in the motor's inability to remain stationary despite the brake being set. Addressing the other options for clarity: a misalignment of the motor typically affects motor performance and could cause mechanical stresses, but it would not directly cause a brake to fail. An overloaded circuit pertains more to the situation where electrical components might fail due to high current, yet this would not directly lead to slipping through the brake. The term "suicide circuit" usually refers to a dangerous wiring configuration that can cause safety hazards but does not directly apply to the issue of the brake malfunction in this context.