Dimming – Switch Dim – (DD1)

The concept of a Switch-Dim system is based upon the Digital Serial Interface (DSI) technology, however there is a difference in that instead of using a DSI controller to transmit the digital signal to the luminaires, it is a simplified dimming method which uses a 230 Volt Mains frequency as a signal transmitter through a simple retractive (non-latching) switch. This means that when the luminaire is switched on, by pressing the retractive switch, the mains voltage is transferred to the regulation system and the different switching and dimming functions are performed depending on the operating status at the time and how long the switch is pressed for. Activating the system with a short press on the switch operates the on/off function and a continuous holding down of the switch will, after a second or two of time, start the system counting the sinewave pulses to fade the connected luminaires up or down.

The Switch-Dim operation is a cost-effective dimming and switching control system using an impulse as the regulator, which is basically a switch with a built-in reversing spring, and as such, the system will work with many of the commercially available push-to-make switches. The control signal corresponds to the line-voltage and dimming is undertaken at a rate of 3 seconds for the function of 1% through to 100%. In theory, there are very few limitations to the Switch-Dim circuit, with a potentially unlimited length of control wire and unlimited number of luminaires, however, in reality, it is suggested that limits are put in place, where the number of luminaires should be restricted, as there can be disturbances between the linearity of luminaires, which can occur when larger numbers of luminaires are placed on the same circuit.

As the control of a Switch-Dim circuit is based upon the push-to-make switch, it has a dimming characteristic which can be aligned to the sensitivity of the eye.

The wiring of a Switch-dim circuit is basically a 3-core and earth connected to each luminaire, where one of the cables is wired into the impulse switch.

Using a Switch-Dim lighting system can provide an ideal solution for many smaller applications, such as, offices, or for stairwells and corridors, as well as for the smaller warehouse or storage area facility.