CA Elevator Mechanic flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Rated load plate

A plate in the car listing the rated load in pounds, the number of persons allowed, and the manufacturer; inspectors verify it matches the machine and rope data.

A17.3 scope

The safety code for existing elevators and escalators; it sets retrofit requirements for car lighting, firefighter service, door restrictors, and pit access on units installed before current code.

Door open time

Under A17.1, power-operated car doors must remain fully open at least 20 seconds at a landing to allow passenger transfer, unless a shorter time is set by a special operating mode.

Leveling tolerance

The car sill must stop within plus or minus 0.5 inch of the landing sill; if the car drifts outside that band, automatic operation must stop and hold the car.

Two-way communication

A17.1 requires a means in the car to call a continuously staffed location, with battery backup and a way to summon help if the primary line fails.

Machine room clearance

At least 18 inches clear in front of controllers and 30 inches clear working space in front of electrical panels; the room may not be used for storage.

Car lighting minimum

A17.3 requires at least 5 foot-candles of light at the car floor with the doors closed, measured at the sill and at the center of the car.

Permit to operate

The current operating permit must be posted in the car; it is issued after a passing periodic inspection and must be renewed before its expiration date.

Rope safety factor

Under A17.1, suspension rope safety factor is at least 12 for traction elevators rated 500 fpm or less, increasing for higher speeds per the code table.

Rope tension equalization

Adjust each rope until it carries within 10 percent of the average tension; unequal tension causes uneven wear on sheave grooves and shortens rope life.

Counterweight runby

At least 2 inches of clearance between the car buffer contact and counterweight buffer contact, ensuring the counterweight does not strike its buffer before the car does.

Motor branch sizing

Branch circuit conductors must be at least 125 percent of motor full-load current, with overload protection in each conductor and short-circuit protection sized per code.

Hydraulic relief valve

The relief valve must open at not more than 150 percent of working pressure; the tank also needs a low-oil or oil-temperature safeguard where the code requires it.

Sheave groove wear

Worn or undercut grooves reduce traction and let the rope sit too deep; measure groove depth and compare to rope diameter to decide on resurfacing or replacement.

Governor trip speed

The governor must trip the car safety at a speed set by the code table, typically 115 to 140 percent of rated speed depending on the speed range.

Equipotential bonding

Rails, machine, controller, and pit equipment are bonded to the building grounding electrode system; verify continuity with a meter before energizing the unit.

Category 1 test

An annual no-load safety test at rated speed with the car empty; the governor trips the safety and the car is verified to stop and hold.

Category 5 test

A full-load safety test at rated speed with rated load, performed every 5 years; it verifies the safety and governor work under maximum load conditions.

Buffer return time

Oil buffers must return to full extension within 90 seconds after compression, and the oil level must be within the marked range on the sight glass.

Door closing force

Power-operated doors must not exceed 30 lbf kinetic energy, and the reopening device must reverse the door on contact with an object in its path.

Troubleshooting sequence

Verify power at the disconnect, then control voltage, then safety circuit continuity, then door lock circuit, then motor and brake circuits, before replacing parts.

Brake holding test

The brake must hold rated load plus 25 percent; check for even shoe contact and air gap within the manufacturer specification during the test.

Rated speed verification

Measure car speed with a recording tachometer; a result outside plus or minus 5 percent of rated speed indicates a drive, sheave, or adjustment problem.

Serious hazard handling

A condition that endangers life or limb requires the unit be taken out of service until corrected, and the finding is recorded with the code section cited.

Lockout/tagout

Isolate the main disconnect, verify zero energy with a meter, apply a personal lock and tag; only the person who applied the lock may remove it.

Pit entry procedure

Stop the car at the landing above, open the pit switch to remove power, and verify the pit stop switch works before entering the pit.

Fall protection threshold

California general industry requires 100 percent tie-off above 6 feet, and guardrails or covers over all floor and shaft openings.

Hoistway opening protection

Barricade the landing opening before work, and use the top-of-car operating station with the car top rail in place when working on the car top.

Confined space testing

Test the pit atmosphere for oxygen and combustibles before entry when there is no permanent ventilation, and wear a retrieval harness.

Electrical PPE

Use voltage-rated gloves and insulated tools on energized circuits; de-energize whenever feasible and treat every circuit as live until verified.

Rigging inspection

Know the working load limit of slings and shackles, never exceed it, use tag lines to control the load, and inspect rigging before each lift.

Emergency response prep

Before starting work, know the manual lowering procedure, the disconnect location, and the entrapment release procedure for the unit.