Attributes . The Caseta ELV+ Smart Dimmer Switch with phase selectable dimming works with up to 250W of dimmable LED, 500W of incandescent/halogen/electronic low-voltage (ELV), or 400-Watt of magnetic low-voltage (MLV); Neutral wire connection and 10-Watt minimum load required for all load types. Out of the box, the dimmer is set to reverse phase for ELV/incandescent/halogen light loads. However, since it is phase selective, the dimmer output can be changed to forward phase for MLV lighting loads and other certain LED . Names