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Modernization of a device or a system has been the primary building block of evolution in any industry, including that of elevating men and materials. Absent replacing a complete system with one of a different nature, progress has steadily been made from "upgrading," "making it better," "tweaking it," "adding a touch here and there," to the sophisticated kind of retrofitting found in more modern times where almost everything but the drive machine, guide rails and car sling are changed. By today's regulations, the changing of the drive machine qualifies as a "new installation." When, in the days of lifting by muscle, an unknown entrepreneur added a counterweight and second rope, winding in another direction, to his windlass, he had a neat modernization on his hands. On the other hand, when James Watt added sun and planet gears to Newcomen's reciprocating steam engine, it was more than a modernization as the new system performed a completely different kind of a task. Often owners, having invested a substantial sum in a steam or gas-powered elevator installation, were reluctant to replace the entire system. They merely used the newly available electric motor to drive the belts to the reduction gearing in place. When revised codes and regulations sought to prevent the spread of fire, modernization took the form of enclosing hoistways. As time went on, control systems became the focus of a new breed of retrofit specialists who strove to save the drive machines and static components but add sophisticated controls. The time came when the appearance of cabins and entranceways became a mark of distinction within a commercial building and the upgrading of these became major renewal items. At the end of World War II, one of the greatest waves of modernization occurred when human operators in the car were replaced by "operatorless control systems."
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