Illumination system with automatic adaptation to daylight level

An illumination system comprising:

• at least one light source;
• a controller for controlling the power output of the at least one light source;
• a light sensor wirelessly communicating with the controller;
• the controller being configured to operate
• in a normal mode, in which the controller is configured to control the at least one light source such that a light level remains substantially constant, and
• in a change mode, in which the controller is configured to control the at least one light source such that the light level is gradually changed with a predetermined change rate so as to decrease a deviation from a target level (LT), the controller being configured to switch from the normal mode to the change mode in response to one or more input signals received from the light sensor;
• wherein the light sensor comprises a memory containing data defining at least one characteristic of a behaviour of the controller and is configured to intermittently measure the light level, and determine whether or not to communicate a transmission signal to the controller based on the measured light level and the data contained in the memory;
• the light sensor being configured to refrain from transmitting the transmission signal when receiving the transmission signal does not cause the controller to change the behaviour of the controller;
• wherein the at least one light source comprises:
• a first group of one or more lamps located proximate to an outside light source, and
• a second group of one or more lamps located farther from the outside light source than the first group of one or more lamps;
• wherein the controller is designed to control a first dim factor of the first group of lamps and a second dim factor of the second group of lamps as a function of a sunlight level Lz, such that the second dim factor is always higher than or equal to the first dim factor;
• wherein dim factor=zero indicates lamp OFF and dim factor=100% indicates lamp fully ON.

A method for adaptation to daylight level using an illumination system comprising at least one light source, a controller for controlling power output of the at least one light source, and a light sensor, the method comprising:

• operating the controller in a normal mode, in which the controller is configured to control the at least one light source such that a light level remains substantially constant;
• operating the controller in a change mode, in which the controller is configured to control the at least one light source such that the light level is gradually changed with a predetermined change rate so as to decrease a deviation from a target level (LT);
• switching from the normal mode to the change mode in response to one or more input signals received from the light sensor wirelessly communicating with the controller;
• storing data defining at least one characteristic of a procedure by which the controller controls the power output of the at least one light source;
• intermittently measuring the light level by the light sensor;
• determining whether or not to communicate a transmission signal to the controller based on the measured light level and the data contained in the memory;
• and
• the light sensor refraining from transmitting the transmission signal when receiving the transmission signal does not cause the controller to change a behaviour of the controller.