In hydraulic elevator systems, emergency power will lower the elevators to the lowest landing and open the doors to allow passengers to exit. The doors then close after an adjustable time period and the car remains unusable until reset, usually by cycling the elevator main power switch. Typically, due to the high current draw when starting the pump motor, hydraulic elevators are not run using standard emergency power systems. Buildings like hospitals and nursing homes usually size their emergency generators to accommodate this draw. However, the increasing use of current-limiting motor starters, commonly known as "soft-start" contactors, avoid much of this problem, and the current draw of the pump motor is less of a limiting concern. COUNT 4
QSN1 How do hydraulic elevators work in emergencies? ANS1 emergency power will lower the elevators to the lowest landing and open the doors to allow passengers to exit QSN2 Once the passengers have exited, what happens? ANS2 The doors then close after an adjustable time period and the car remains unusable until reset, usually by cycling the elevator main power switch QSN3 For what reason are hydraulic elevators not powered by the standard emergency system? ANS3 due to the high current draw when starting the pump motor QSN4 What are current-limiting motor starters referred to as? ANS4 "soft-start" contactors