| Elevator servicing A method of servicing an elevator system having a plurality of control elements operable between first and scond states, comprising the steps of: providing monitoring means having storage means and a Elevator servicing plurality of input leads, storing definitions in the storage means to said Elevator servicing monitoring means for at least certain ones of said plurality of input leads, with each of said definitions being associated with a control element of the elevator system, selecting which control elements of the stored definitions, and the states thereof, are to signify the occurrence of an event by the simultaneous occurrence of Elevator servicing the specified states,  The elevator business may, as the old joke goes, have its ups and downs, but these days the downs in the elevator repair business are greatly outnumbered by Elevator servicing the ups. As many of the elevator motors in older buildings across the U.S. have come to the end of their lives, a revolution in motor control has reached maturity. Companies that service elevators are not only replacing and refurbishing old machines but are also participating in the installation of Elevator servicing state-of-the-art controls. One company that's benefiting from this confluence of market demands is H&H Industrial Motor Services of this Chicago suburb, a longtime elevator service Elevator servicing company that's busy these days with the huge elevator market of downtown Chicago. It's a market in the midst of transformation, and H&H is on the front line.  "The age of the equipment in the elevator industry is getting to be critical," observed H&H vice president Larry Fulgenzi one recent day as the traditionally busy summer season was getting under way. At the same time that older machines are reaching the end of their lives, "people are Elevator servicing trying to gain some benefit from the new technology," he said. This means increased sales of both service and products. Advertisement Added company president Tom Green: "The technology [of elevators] is changing at a very rapid rate," and this is providing opportunities for those with the expertise to refurbish or upgrade them Elevator servicing . Geared, gearless, and hydraulic H&H services all three kinds of elevator systems-geared, gearless, and hydraulic. "The gearless is a direct-drive machine that gives you a reduction in speed," explains Green Elevator servicing , while a geared machine provides a means of controlling speed. In a hydraulic system, a motor pumps oil-or, rarely, water-in and out of a reservoir to force the piston supporting the cab up or down. The drawback of a hydraulic system is that it is limited to a certain height and speed. Although hydraulic systems are somewhat easier to maintain than geared or gearless types, H&H is servicing fewer and fewer hydraulic pump motors Elevator servicing . Still, thousands of hydraulic systems remain in service in Chicago-more, in fact, than geared or gearless, by Fulgenzi's estimate. Hydraulic elevator pump motors are, Elevator servicing without exception, alternating current. Probably all but 5% of geared and gearless applications arc direct current. "Hundreds, maybe as many as a thousand hydraulics arc installed in the Chicago area every year," Fulgenzi estimates. By contrast, no generators are being put into new installations. "Consultants are still not completely sold on d-c," Fulgenzi says, but even where d-c is chosen, the control will invariably be a static drive, not a generator. Consider McCormick Place, Chicago's lakefront convention center. Two-thirds of the elevators there are hydraulic. In a structure with such a low profile, hydraulic elevators are more economical Elevator servicing . That's why they're also more common in the suburbs, where there are fewer tall buildings Elevator servicing . "Geared machines are generally used up to about 25 to 30 landings, but at a specific speed and capacity," says Fulgenzi. Gearless machines are used for applications of greater height that require high speed. An extreme example of a gearless application is the Sears Tower, where the elevator that travels express from street level to the observation deck moves at 1,600 feet per minute. The Petronas Towers in Kuala Lumpurthe tallest buildings in the worldhave elevators that travel at about 2,000 feet per minute. A new gearless installation in Taipei will travel at 3,500 feet per minute-more than twice as fast as the Sears Tower elevator. Many if not most elevator systems still use motor/generator sets, although these are gradually being replaced with a-c motors in combination with solid-state controls Elevator servicing . (The exceptions are those installations where the consultants are "not completely sold on a-c.") A high degree of control precision is needed in elevators, and motor/generator sets provide this precision, the drawback being that generators can be difficult to maintain. An informal survey conducted by Fulgenzi revealed that 40% to 50% of elevator equipment in Chicago still has some sort of generator or a d-c motor, "and that's in direct contrast with what's being sold," he says. The other 60% or so is newer a-c with solid-state control Elevator servicing . There are still about 10,000 or 12,000 units in Chicago that have some sort of generator. Usually, if an elevator stops running for about 20 minutes, it goes into shutdown mode. If the elevator stops a few inches above or below a floor, that's likely a sign of a generator failure. Failed generators are usually pulled and rewound in the shop. (Sometimes only the armatures Elevator servicing , not the frames, are pulled.) Geared application motors, by contrast, are always rewound in the shop. Motors for gearless applications are almost always rewound on-site, the exception being small ones. Why the difference? It's mainly a matter of size and weight. A geared machine may weigh only 400 to 500 lbs., but a gearless one may weigh as much as 12,000 lbs. "You almost have to limit size and weight to what the building freight elevator will allow you to get down," says Fulgenzi Elevator servicing . Another factor is the configuration of the machine room. A higher ceiling or otherwise cramped quarters might make removal prohibitively expensive. Underlying it all is the cost of labor. Elevator equipment is removed by elevator union members Elevator servicing , who according to Fulgenzi are among the most highly paid union workers in the city. |