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Operating panels and buttons
"The buttons". The way you communicate with the elevator.
All the buttons and displays you know: the panel inside the car whose buttons you use to choose a floor, control the doors or press the alarm button, and the buttons on every floor that call the elevator. They are the go-between between you and the brain. It looks simple, but think about what happens when several buttons inside the car and several buttons on different floors are pressed at the same time. That information is sent to the control panel, processed, and turned into operating commands for the elevator and a particular order in which it will travel.
Fun factOn floors with a button panel that lets you call the elevator both up and down, many people press both arrows together, thinking it will come faster that way. What they are really doing is sending the control panel two calls instead of one. The controller then has to plan the elevator's route so it answers both calls, so they actually cause a delay for themselves, and for everyone waiting with them, in reaching the floor they want.