An electronic circuit for protecting a load against over-voltage is disclosed. The electronic circuit comprises an input port for receiving a voltage and an output port for feeding the voltage to the load. The electronic circuit further comprises a switching unit arranged to switch on and off the voltage from the input port. Moreover, the electronic circuit comprises a capacitive component arranged to receive the voltage when the switching unit is switched on and is otherwise arranged to feed voltage to the output port. Furthermore, the electronic circuit comprises a comparing unit configured to control the switching unit to be switched off when a value at the output port exceeds a first threshold; and to control the switching unit to be switched on when the value is below a second threshold.

Systems and methods for detection of interconnected outputs of a power supply are provided. A first channel of a power supply is activated, such that power is supplied to a first load connected to the first channel. A first load voltage is measured for the first load. A second load voltage is measured for a second load connected to a second channel of the power supply. The second load voltage is compared to the first load voltage to generate an interconnection result. The power supply is shut down when the interconnection result indicates that the second load voltage matches the first load voltage, such that all channels of the power supply do not supply power to any load connected thereto.

A device may include a power source, two or more lamps for providing light, and a controller. The controller may be configured to periodically select a first combination of one or more of the lamps, provide power from the power source to the first combination of the lamps, select a second combination of one or more of the lamps, and switch the power from the first combination of the lamps to the second combination of the one or more of the lamps after a period of time has elapsed.

In at least one embodiment, a light source apparatus includes a discharge lamp with a pair of electrodes and a driving unit that supplies a driving current to the pair of electrodes. The driving unit includes an AC supplier that supplies an alternating current to the pair of electrodes and a DC supplier that supplies a direct current to the pair of electrodes. The AC supplier is configured to alternately repeat an AC supply section in which the alternating current is supplied and an AC stop section in which the supply of the alternating current is stopped. The DC supplier is configured to supply the direct current during a period corresponding to the AC stop section. A frequency of the direct current is not lower than 10 Hz and not higher than 1 kHz.

Lighting power supply system (1) including a mains input converter (11) operable to provide power, a controller (17) operable to control at least one element of the lighting system, a controller bus (26) and a controller interface (25) operable to provide control signals from the bus to the lighting system. An auxiliary converter (43) powers the lighting system from the bus and it may allow the controller to continue to be powered when the mains input is absent and an emergency battery (19) is depleted.

A technique for controlling a luminaire using a controller preprogrammed to cause the luminaire to carry out a predefined action as a response to an occurrence of a predefined triggering condition is provided. The technique comprises storing, into a memory, status indications received in the status indication messages from the other devices, analyzing the stored status indications in an attempt to identify a sequence of one or more status indications that repeatedly precede an occurrence of said predefined triggering condition, and reprogramming, in response to identifying a sequence of status indications that repeatedly precede an occurrence of said predefined triggering condition, the controller to cause the luminaire to initiate or to carry out a preparatory action for carrying out said predefined action as a response to reception of said identified sequence of status indications.