IL Elevator Mechanic cheat sheet

Illinois adopts the Safety Code for Elevators and Escalators (ASME A17.1/CSA B44) as its technical standard; the Illinois Elevator Safety and Regulation Act (225 ILCS 320) supplies licensing, permitting, and inspection authority.

A17.1 scope covers elevators, dumbwaiters, escalators, moving walks, and material lifts; each unit type has its own Part (Part 2 electric elevators, Part 3 hydraulic, Part 5 escalators/moving walks).

Escalator key dimensional limits: nominal width 24 in/600 mm or 40 in/1000 mm; maximum rise per unit 60 ft unless a code variance is granted; rated speed not more than 125 ft/min (0.63 m/s) with a maximum 5% variation.

Escalator clearance rules: vertical clearance above the step tread not less than 90 in (2.3 m) to any obstruction; minimum 40 in (1 m) horizontal clearance from the handrail outer edge to any wall or obstruction.

Escalator balustrade deck: the skirt panel must extend at least 10 in (250 mm) above the step nose, and the combplate teeth must mesh with the step cleats with total clearance not exceeding 3/16 in (4.8 mm) in the direction of travel.

Elevator car inside dimensions and door size are governed by the applicable occupancy/accessibility rules; a car used for stretcher service requires a clear inside depth of at least 7 ft with a 42 in door.

A17.1 requires a certificate of operation posted in the car and a periodic re-inspection interval set by the authority having jurisdiction; Illinois uses annual inspection with a certificate valid for one year.

Machinery space and pit requirements: pit access by a ladder with a maximum 12 in rung spacing, a pit ladder extending to within 12 in of the pit floor, and a pit light with a switch at the pit access door.

New installations must include a means to prevent the car from moving with the hoistway door unlocked more than 2 in from the landing, except under the restricted leveling/loading zone rules permitted by the code.

Traction drive: the car is lifted by ropes over a sheave driven by a geared or gearless machine; the counterweight balances roughly the car plus 40-50% of rated load, and the machine must provide sufficient traction to lift 125% of rated load.

Hydraulic drive: a pump driven by an AC motor forces oil into a jack (single-stage or telescopic) to raise the car; lowering is by gravity with the oil returning through a valve.

Hydraulic system pressure is limited by the code to 2.5 times the pressure required to lift the rated load; the relief valve must be set to open at no more than that value.

The hydraulic relief valve setting is typically verified with the car at rest and the pump running against the closed valve; the pressure gauge reading is the reference for the setting.

Jack types: single-stage (plunger travels the full car rise), telescopic (multiple concentric plungers), and holeless (used where a below-grade jack hole is not possible).

Traction machine components: sheave, brake, motor, and (for geared machines) a worm gear reducer; gearless machines use a direct-drive permanent-magnet or DC motor on the sheave shaft.

Roping: 1:1 roping moves the car at the same speed as the rope; 2:1 roping requires twice the rope travel and half the rope tension for the same load, so rope speed is twice car speed.

Hydraulic oil temperature affects viscosity and thus car speed; oil that is too cold raises pressure and slows the car, so the reservoir and system must be kept within the manufacturer's temperature range.

A traction elevator's governor tripping speed is set above the rated speed (typically 115-125% of rated speed) so the safety applies before the car can reach an unsafe speed.

The controller is the logic center: it sequences door operation, car travel, and safety circuits; modern systems use a microprocessor or PLC with a serial communication link to car and hall fixtures.

The safety chain is a series circuit of normally closed switches (pit, car top, door locks, governor, slack rope, final limits); any open switch stops the car and prevents further motion until reset.

Door interlocks are part of the safety chain and must prevent the car from starting unless the landing door is closed and locked; the interlock must be positively operated, not held closed by gravity alone.

Motor control: AC induction motors are commonly driven by a variable-frequency drive (VFD) for smooth acceleration and leveling; DC motors use a motor-generator set or a solid-state SCR drive.

Wiring color and identification: conductors must be identified at each end; the equipment grounding conductor must be green or green with yellow stripe and be bonded to the machine, controller, and car frame.

The main line disconnect must be lockable, located where it is accessible to the mechanic, and must open all ungrounded conductors; it must not be located in the hoistway or pit.

Car and hoistway wiring must be supported at intervals not exceeding 5 ft (1.5 m) for traveling cables and be protected from abrasion at the car and counterweight.

A ground fault on the car or in the hoistway is detected by the ground fault circuit or by insulation resistance testing; a low-resistance reading to ground indicates a fault requiring repair before return to service.

The car safety (governor-operated) applies wedges or rollers to the guide rails when the car overspeeds in the down direction; the governor must trip at 115-125% of rated speed and the safety must stop and hold the car.

The governor rope must be kept under tension by a tension sheave and weight; a slack or broken governor rope will not trip the safety, so the tension device must be checked during maintenance.

The final limit switch is a separate, non-resettable device that stops the car if it overtravels past the normal terminal landing; it must be reset by a mechanic, not by the car operator.

The pit switch, car top inspection station, and emergency stop must all be functional; the car top inspection station must allow the mechanic to run the car at reduced speed with the doors open under the code's restricted conditions.

The door operator and door protective device (mechanical safety edge or infrared curtain) must reverse the door on contact or obstruction; the reopening force must not exceed the code limit (typically 30 lbf for the leading edge).

Maintenance intervals: monthly for the machine room and controller, quarterly for the pit and car top, and annual for the full safety test (safety, governor, buffers, and door interlocks).

The annual safety test must be performed by a licensed mechanic and documented; the test includes the car safety, counterweight safety, governor tripping speed, buffer operation, and door interlock function.

Escalator inspection items: step/skirt clearance, combplate teeth, handrail speed and tension, brake stopping distance, and the emergency stop button at each landing.

A hydraulic elevator's annual test includes the relief valve setting, the jack and piping for leaks, the lowering valve, and the slack rope/chain device where installed.

Insulation resistance testing (megger) is performed with the circuit de-energized and isolated; a reading below the manufacturer's minimum (often 1 megohm) indicates degraded insulation requiring repair.

A shorted or grounded safety chain switch can be bypassed only for troubleshooting and must be restored before the car is returned to service; bypassing a safety device is prohibited.

The car top inspection station must have a stop switch and a means to run the car; the station must be within reach of the mechanic on the car top and must be clearly marked.

Motor overload protection must be sized to the motor's full-load current; an undersized heater or setting will trip on normal acceleration, while an oversized one will not protect the motor.

Phase reversal or single phasing on a three-phase motor will cause the car to run in the wrong direction or not at all; a phase monitor or correct wiring sequence is required.

The emergency phone or alarm in the car must be tested monthly and must connect to a monitored location; the code requires two-way communication from the car to a person who can take action.

The fire service key switch (Phase I) must recall the car to the designated landing and open the doors; Phase II allows firefighters to control the car with the doors open under restricted conditions.

Buffer types: oil buffers are required for car speeds above 200 ft/min and must be kept filled to the marked level; spring buffers are allowed only for lower speeds.

The counterweight must have a buffer or a block that limits its travel, and the counterweight safety (where required) must be tested at the same time as the car safety.

Rope inspection: broken wires, corrosion, and reduced diameter are grounds for replacement; the code requires rope replacement when the number of broken wires in a lay exceeds the manufacturer's limit.

Guide rail alignment and lubrication affect ride quality and safety; rails must be plumb and the guide shoes or rollers must be adjusted to the manufacturer's clearance.

The traction machine brake must set automatically when power is removed and must hold 125% of rated load; the brake gap and lining wear are checked during maintenance.

Hydraulic lowering valve must control descent speed; a stuck valve can cause the car to drop, so the valve and its manual lowering feature must be tested.

Pump and motor alignment, coupling condition, and oil level are checked at each maintenance visit; low oil causes cavitation and noisy operation.

The pit must be kept clear of water and debris; standing water is a slip and electrical hazard and must be corrected before the car is returned to service.

The car top railing (where required) must be at least 42 in high with a midrail; the car top must be able to support the mechanic's weight and be free of obstructions.

The machine room must be locked, ventilated, and kept at a temperature within the equipment rating; it must not be used for storage of unrelated materials.

The governor tripping speed is verified by a tachometer or by the manufacturer's test procedure; the recorded value must fall within the code range for the rated speed.

The annual inspection report must list deficiencies and the corrective action taken; the certificate of operation is issued only after deficiencies are corrected and reinspected.

Escalator brake stopping distance must be within the manufacturer's specified range; excessive distance indicates worn brake lining or a misadjusted brake.

The handrail must move at the same speed as the steps within the code tolerance; a mismatch indicates a worn drive or a slipping handrail drive.

A17.1 requires a means of access to the pit that does not require the car to be moved; the pit ladder must be securely fastened and extend to within 12 in of the pit floor.

Hoistway door locking: the door must be locked when the car is not at the landing, and the lock must be released only by the car's arrival at that landing within the leveling zone.

The car door must have a reopening device that operates if the door meets an obstruction; the device must be tested at each maintenance visit.

Escalator step demarcation: the step edges must be marked with a contrasting color, and the step tread must be slip-resistant.

The escalator must have a skirt guard and a step/skirt clearance that prevents entrapment; the clearance is checked with a gauge during inspection.

The escalator emergency stop button must be located at each landing and must be clearly marked; it must stop the escalator within the code's stopping distance.

The controller must have a disconnect means within sight of the controller and must be lockable; the disconnect must be marked with the equipment it controls.

Traveling cables must be supported and guided so they do not rub on the car or hoistway; a worn cable can short and cause a ground fault.

The car light and fan circuits are separate from the control circuit; a failure in the lighting circuit must not affect the safety circuit.

The emergency lighting (if required) must be tested and must provide illumination for the code-specified time after power loss.

The fire alarm interface must be wired so that a fire alarm signal recalls the car to the designated landing; the interface must be tested during the annual inspection.

The hydraulic jack must be protected against overpressure by the relief valve and against runaway by the rupture valve (pipe rupture valve) where required.

The hydraulic system must have a means to lower the car manually in an emergency; the manual lowering valve must be accessible and operable by the mechanic.

The traction machine must be mounted on a substantial foundation; vibration and misalignment cause bearing wear and rope wear.

The sheave groove profile must match the rope diameter; a worn groove reduces traction and can cause rope slippage.

The motor must be protected against overheating by a thermal sensor or overload; a hot motor indicates overload, low voltage, or a mechanical bind.

The car safety must be tested with the car empty and at the rated load; the test verifies that the safety stops and holds the car without excessive deceleration.

The governor must be tested for tripping speed and for the force required to trip the safety; the governor rope must be free of kinks and wear.

The buffer must be tested for compression and return; an oil buffer that does not return to its extended position must be repaired before service.

The door interlock must be tested at each landing; the car must not start unless the door is locked and the interlock circuit is complete.

The emergency phone must be tested monthly; the call must reach a monitored location and the response must be documented.

The certificate of operation must be posted in the car and must show the inspection date and the expiration date.

The authority having jurisdiction may require additional inspections after an accident or a change in the installation.

The code requires that the machine room be kept locked and that only authorized personnel have access.

The escalator must have a clearance of at least 40 in from the handrail to any wall or obstruction; the clearance is measured at the handrail outer edge.

The escalator step width must be 24 in or 40 in; the step must be marked with a contrasting color at the edges.

The safety chain must be tested by opening each switch in turn and verifying that the car stops and cannot restart until the switch is reset.

The door operator must be adjusted so that the door closes with sufficient force to latch but not enough to injure a passenger; the closing force is checked with a gauge.

The car top inspection station must be tested for stop, up, and down functions; the station must be within reach of the mechanic.

The main line disconnect must be tested for lockout/tagout; the disconnect must open all ungrounded conductors and must be lockable in the open position.

The hydraulic oil must be kept clean and at the correct level; contaminated oil causes valve sticking and pump wear.

The traction ropes must be inspected for broken wires, corrosion, and wear; ropes that fail the inspection must be replaced as a set.

The machine brake must be tested for holding capacity; the brake must hold 125% of rated load without slipping.

The motor and pump must be checked for alignment and coupling wear; misalignment causes vibration and premature failure.

The pit must be inspected for water, debris, and proper lighting; the pit switch must be tested for function.

The car top must be inspected for railing condition, lighting, and the inspection station; the car top must be clean and free of obstructions.

The machine room must be inspected for ventilation, temperature, and housekeeping; the room must be locked and free of stored materials.

The annual inspection report must be retained and made available to the authority having jurisdiction.