Scope an elevator modernization from a single-speed or older AC/DC drive to a VVVF (variable-voltage, variable-frequency) drive, including when machine-room-less (MRL) retrofit is feasible

Steps

1. Confirm the existing equipment's drive type, hoistway dimensions, pit depth, and overhead clearance from as-built drawings or a field survey before assuming any modernization path
2. For a VVVF drive upgrade, confirm the new controller/drive is compatible with the existing motor, governor, and safety-device wiring, or whether those must be replaced as part of the same scope
3. For a machine-room-less retrofit, confirm the existing hoistway footprint, pit, and overhead can accommodate a gearless MRL drive unit within the shaft per the manufacturer's engineering data, since MRL units are designed to fit within standard shaft dimensions but still have minimum clearance requirements
4. Identify whether any dimension falls short of current code minimums (pit depth, overhead, refuge space) and, if so, confirm whether the AHJ has a variance/alternative-compliance process rather than assuming the modernization is a straightforward like-for-like swap
5. Confirm which retroactive code requirements (e.g., door lock monitoring, firefighters' service upgrades) will be triggered by the modernization filing itself, since a modernization permit can obligate compliance with current retroactive rules beyond just the drive change