NEIEP Mechanic Exam key terms

A centrifugal safety device driven by the car or counterweight that detects overspeed and trips a mechanical safety to stop and hold the conveyance.

A gripping assembly mounted on the car or counterweight frame that clamps the guide rail when tripped, stopping and holding the unit under load.

Any condition where the conveyance travels faster than its rated or governed speed, triggering protective devices such as the governor and safety.

A machined steel track fixed in the hoistway that constrains car and counterweight travel and provides the surface the safeties grip.

A sliding or roller assembly on the car and counterweight frame that rides the guide rail to maintain alignment and reduce lateral sway.

A guide assembly using wheels or rollers instead of sliding gibs to follow the rail, reducing friction and allowing higher travel speeds.

The grooved driving wheel of a traction machine whose friction with the hoist ropes moves the car and counterweight.

The geared or gearless power unit that drives the traction sheave and includes the motor, brake, and often the reduction gearing.

A steel wire rope that suspends the car and counterweight and transfers drive force from the sheave; ropes are inspected for wear and broken wires.

The adjustment of individual hoist rope tensions so each rope shares load evenly, preventing premature wear and uneven car leveling.

A weighted frame on guide rails connected to the car by ropes or chains to balance car weight and reduce required motor effort.

A chain or cable hung under the car and counterweight to offset the changing weight of the hoist ropes as the car moves.

A spring-applied, electrically released friction brake on the traction machine that holds the car at rest and stops it on power loss.

The electromagnetic coil assembly that, when energized, lifts the brake armature against spring force to release the machine brake.

The measured clearance between the brake armature and the magnet or drum when the brake is released, set to manufacturer specification.

The motorized assembly mounted on the car that opens and closes the car doors and engages the hoistway door interlock mechanism.

A mechanical and electrical device on each hoistway door that prevents car motion unless the door is closed and locked.

The coupling on the car door operator that engages the hoistway door vane to move the landing door with the car door.

The vertical band of travel at a landing where the car door can be unlocked and opened; typically defined by zone switches or sensors.

The controlled positioning of the car floor with the landing sill within tolerance, using leveling switches or sensors and the drive control.

In hydraulic elevators, the manifold assembly that controls oil flow to raise, lower, and level the car, including relief and check functions.

A cylinder and plunger that lifts a hydraulic elevator car by pressurized oil, either directly or through roping.

The space below the lowest landing floor level that houses buffers, pit switches, and equipment, and must be kept clear and dry.

A spring or oil-filled energy-absorbing device in the pit that stops the descending car or counterweight if it overtravels the lowest point.

Travel of the car or counterweight beyond the normal terminal landing limits, limited by final limits and buffers.

A switch that opens the drive circuit if the car passes the normal terminal stopping point, preventing further travel toward the overtravel.

A manually operated switch in the pit that, when opened, removes power from the car and prevents movement while a mechanic works below.

The procedure of isolating and locking energy sources and attaching warning tags before service, ensuring equipment cannot be re-energized unexpectedly.

The service switch that removes incoming power from the elevator controller and machine, used for isolation during maintenance.

The panel of relays, contactors, boards, and logic that governs starting, stopping, door operation, and safety circuits of the conveyance.

A series electrical chain of safety switches and contacts that must be closed for the car to run, opening on any unsafe condition.

A drive scheme that varies motor voltage and frequency to control speed and torque smoothly, common in modern gearless traction elevators.

A sensor that reports motor or sheave position and speed to the drive, enabling accurate leveling and closed-loop speed control.

A moving tread unit linked in a continuous chain, guided by tracks and kept level through the ride except at the landings.

The roller chain loop that connects and drives the escalator steps, tensioned and inspected for elongation and roller wear.

The toothed plate at each escalator landing that meshes with step cleats to clear debris and provide a safe transition.

The stationary side panel along an escalator balustrade that guides passengers and houses the skirt guard and safety switches.