Dimming Protocols

0–10 V is one of the most basic electronic lighting control signal systems.The control signal is a DC voltage that varies between zero and ten volts applied to the control input. The controlled lighting should scale its output so that at 10 V, the light should be at 100% output, and at 0 V it should at 0% output (off).Dimming drivers offer variable changes to the output from intermediate voltages between 0 and 10v, giving output curves that are linear.

DMX or DMX512 (Digital Multiplex) is an industry standard for digital communication networks that are commonly used to control lighting and effects.It has rapidly become the primary method for linking lighting controllers and drivers for intelligent lighting in professional applications.DMX512 employs EIA-485 differential signalling in conjunction with a variable-size, packet-based communication protocol. It is unidirectional. The 512 refers to the number of channels in one network segment where this segment is also referred to as a "universe".

DALI (Digital Addressable Lighting Interface) is a data communication protocol jointly developed by several manufacturers of lighting equipment and forms an international standard (IEC62386) adopted globally for professional lighting. The common platform of DALI operates on a 2-wire system and enables equipment from different manufacturers to be connected together.

Phase cut dimming drivers are referred to as Triac dimmers and "chop" the AC voltage waveform preventing the voltage from being supplied at full value. There are two types of mains dimmer; leading edge and trailing edge deriving their names from the part of the AC wave that they cut off. Trailing edge dimmers are now the more popular of the two types having several advantages over leading edge dimmers including smoother control, soft start and silent operation. Triac dimmer modules may be used in conjunction with compatible LED drivers to control the light output (brightness) of connected LED lamps. The latest intelligent Triac LED drivers feature high compatibility with the wide range of available dimmer module brands and high stability at low currents preventing flicker.

PWM (Pulse Width Modulation) dimming controls the light output by varying (or modulating) the duty cycle of a constant current supplied to the LED module/string to effectively change the average current supplied.