An elevator car is conventionally illuminated with incandescent lamps, but also different types of fluorescent tubes and, nowadays, also e.g. LED illuminators are used in order to conserve energy.
In old elevator systems the lighting of the elevator car is always kept on. For energy-saving reasons, however, controls have been developed with which it is endeavored to always switch off the lighting when there are no passengers in the elevator car. This control arrangement results in the lamps of the elevator car being continuously extinguished and ignited.
Continuous extinguishing and igniting of the lamps shortens the lifetime of the lamps. For example, igniting an incandescent lamp generates an ignition current peak, which is caused by the fact that the resistance of a cold incandescent filament is low. As the incandescent filament warms the resistance grows and the current diminishes.
Light dimmers are also used in the lighting of an elevator system, in which case the lamps are never extinguished to be totally de-energized, and they do not ever cool completely. The aim is to reduce switching current peaks with this arrangement.
Publication US 2004/0188182 A1 discloses a control arrangement for conserving the energy of lighting. When an elevator is unused for 5 minutes, the lights and the fan are extinguished and are switched on again when the elevator has received a landing call. A problem of this solution is, on the one hand, that re-ignition of the lamps generates an ignition current peak, which weakens the lifetime of the lamps and, on the other hand, that the control of the lighting requires control feedback from the control of the elevator system, which complicates the structure of the control and makes installation more difficult.
Publication JP 8245090 presents a control arrangement of lighting, in which when the elevator car is empty the lights are dimmed in order to conserve energy. This solution also requires feedback from the control of the elevator system, in which case the structure of the control is complicated and e.g. retro-fitting the control in the elevator system is awkward.
Publication GB 1392951 A presents keeping the lighting of an elevator car extinguished when the elevator is standing unused and the delivery of the ready illuminated elevator car to the call floor for an order.