Maintenance, Inspection & Troubleshooting Flashcards
7 cards from real CET practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Maintenance, Inspection & Troubleshooting flashcards as text
A hydraulic elevator slowly drifts down when stopped at a floor with a heavy load. The MOST likely cause is:
Answer: A leaking packing or a worn check valve at the valve unit
Downward drift under load typically indicates a leak past the valve unit check valve or cylinder packing, allowing fluid to bypass back to the tank.
What is the function of the 'leveling zone' in a modern elevator control system?
Answer: A defined range above and below a floor where the car can inch to precise floor level
The leveling zone is a narrow band (typically ±3 to 6 inches from floor level) within which the car is permitted to creep at reduced speed to achieve precise floor alignment.
When inspecting wire rope on a traction elevator, which condition alone is sufficient cause for immediate rope replacement?
Answer: A kink in any portion of the rope
A kink permanently deforms the wire rope's internal structure, concentrating stress at that point and requiring immediate replacement regardless of other wire condition.
A traction elevator makes a loud 'thud' when stopping at floors. The MOST probable mechanical cause is:
Answer: Worn brake lining causing the brake to apply too quickly
Worn brake linings can cause the brake to slam on suddenly rather than applying smoothly, producing an audible thud felt throughout the car.
Which ASME A17.1 rule requires that escalator handrails be checked to ensure they move in the same direction and at approximately the same speed as the steps?
Answer: Rule 8.6.1.1
ASME A17.1 Rule 8.6.1.1 (periodic inspections for escalators) includes verifying handrail speed relative to step speed to prevent passenger falls.
A technician notices the elevator car vibrates excessively during travel but the vibration stops once the car enters the leveling zone. This symptom most likely points to:
Answer: Guide rail joint misalignment or a loose rail bracket in the mid-hoistway section
Vibration limited to travel speed that disappears at low leveling speed typically indicates a rail irregularity — joint step, worn splice, or loose bracket — causing resonance at higher speeds.
What does it mean when an elevator's 'car top inspection station' is placed in the 'INSP' mode?
Answer: Normal automatic operation is disabled and car movement is controlled only from the car top
Placing the car top station in INSP mode disables normal operation and restricts all car movement to the car top station at a reduced inspection speed, ensuring technician control.