Car Top Inspection Station Fails Intermittent Check
An inspector is performing a periodic inspection on a 3,000 lb (1,360 kg) geared traction freight elevator in a warehouse. The car top inspection station has a three-position switch (NORMAL, INSPECTION, ACCESS) and a handheld unit on a coiled cord. During the check, the inspector finds that with the switch in INSPECTION the car moves only when the handheld unit's UP button is held, but the DOWN button produces no motion. The inspector also finds that the car will move at normal speed when the switch is in the ACCESS position with the handheld unit connected. The maintenance log shows the inspection station was rewired three months ago after a cord replacement. The car serves three floors and the warehouse needs it for shipping.
1. Identify the safety-significant findings and explain why each one matters, independent of whether the car 'works.'
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Two findings are safety-significant:
- No DOWN motion in INSPECTION. Inspection operation is the mode used by mechanics who are on the car top or in the hoistway. Loss of one direction means the mechanic cannot move the car away from a hazard in that direction under controlled inspection speed. This is not a convenience issue; it removes a required means of controlled movement during maintenance.
- Normal-speed movement in ACCESS with the handheld connected. ACCESS is a mode intended to allow limited movement for a specific purpose, not normal passenger-speed travel. If the car moves at normal speed in ACCESS, the speed limitation and the controlled-movement intent of that mode are not being met. A mechanic on the car top or in the pit could be exposed to unexpected fast movement.
Both findings point to the same root: the rewiring three months ago. A cord replacement that altered the inspection circuit is the most likely cause of a direction-specific failure and a mode-specific speed failure. The inspector should treat the wiring as suspect, not the buttons, and should not accept the car on the basis that it moves in one direction.
2. The building owner wants the car left in service because 'the mechanic can still use the UP button.' How should the inspector respond, and what must happen before the car is returned to service?
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The inspector should reject that reasoning. Inspection mode is required to provide controlled movement in both directions at inspection speed; having only UP means the mechanic cannot retract from a position that requires DOWN movement, and it forces improvisation in a hazard zone. The ACCESS-mode normal-speed finding is independently disqualifying.
The car should be removed from service until:
- The inspection station wiring is traced against the manufacturer's diagram, with particular attention to the direction circuits and the ACCESS-mode speed limiting.
- The DOWN circuit is restored and proven under load, not just by hearing the contactor pick up.
- ACCESS mode is verified to limit speed as designed and to prevent unintended normal-speed travel.
- A functional test of all three switch positions and both directions is documented, along with the as-found and as-left conditions.
The inspector's report should record the as-found defects and the corrective actions, and the car should not be released on a verbal assurance.