Abstract: A lighting device includes an LED light source (20) operable by electric power supplied to the device, and a control system (23) receiving electric power from an external power supply (26) and supplying power to the light source (20). The control system (23) also being operable of operating in a second mode to supply power to the light source (20) only on receipt by the control system (23) via the power supply (26) of a signal identifying said device. Thus the device (24) can be incorporated in a conventional lighting circuit or a circuit in which the devices (24) are individually controlled.

Abstract: An LED light assembly comprises an aluminium extrusion cut to length to form a heat sink (20) with a hollow interior that may be semi-circular in cross-section or any other convenient cross-section to allow air flow through the heat sink and including a mounting surface (21) for supporting and conveying heat from an LED light source (62) mounted on the surface. The extrusion has a heat dissipating surface (24) with fins (27) for receiving and dissipating heat from the LED light sources (62) on the mounting surface (21). The fins (27) support items such as anchors (45), brackets (37) and casings (28, 35) also formed by lengths of respective extrusions and a sliding fit on the heat sink (20).