Tubular lighting device, luminaire and method for operating with an electronic ballast

A retrofit tubular lighting device for operating with an electronic ballast, wherein the electronic ballast is arranged to supply a plurality of fluorescent lamps, the tubular lighting device comprising:

• first connection pins (p1, p2) for coupling to a first output of the electronic ballast;
• second connection pins (p3, p4) for coupling to a second output of the electronic ballast;
• a first filament emulation circuit coupled to the first connection pins;
• a second filament emulation circuit coupled to the second connection pins;
• a lighting element;
• a driver coupled to the first filament emulation circuit, the second emulation circuit, a first battery and the lighting element, wherein the driver is arranged to provide a charge to the lighting element and the first battery;
• the first battery for storing the charge provided by the driver and providing the charge to the lighting element;
• a controller comprising a communication device for sending, when the charge of the first mentioned battery is below a first threshold, a first charging signal to a further retrofit tubular lighting device comprising a further battery and being coupled to the electronic ballast, and wherein the communication device is further arranged for receiving a second charging signal from the further retrofit tubular lighting device, wherein the second charging signal indicates that a further charge of the further battery is below a second threshold,
• wherein at least one of the first filament emulation circuit and the second filament emulation circuit is arranged to provide power from the electronic ballast to the driver when the communication device receives the second charging signal indicating that the further charge of the further battery is below the second threshold.