Types of Dimmers Each type of lighting source (load types) has individual characteristics, which require special types of dimmers. It is important to use a dimmer that is designed, tested, and CE rated for your specific lighting source/load type:
|
|
|
|
Incandescent/Halogen: Line-voltage tungsten filament lamps, including line-voltage (220-240V) halogen lamps | |
Electrical characteristic | Resistive | Special requirements | Rated for cold filament inrush (positive and negative periods may not be equal, resulting in a net DC voltage). Do not use on magnetic low-voltage (MLV) or Electronic low-voltage (ELV). |
|
|
|
Magnetic Low-voltage (MLV): Magnetic (core and coil, toroidal) transformer-supplied low-voltage lighting (6, 12, or 24 V) | |
Electrical characteristic | Inductive | Special requirements | Symmetric cycles (VDC ≤ 2), smooth turn off (positive and negative periods are equal for safe MLV transformer operation). Include transformer losses when calculating the load. |
|
|
|
Electronic Low-voltage (ELV): Electronic (solid-state) transformer-supplied low-voltage lighting | |
Electrical characteristic | Capacitive | Special requirements | Very smooth turn on. Neutral wire connection |
|
|
|
Neon/Cold Cathode (Magnetic Ballast): Magnetic (core and coil, toroidal) transformer-supplied
Electrical characteristic | Very inductive | Special requirements | Symmetric cycles (VDC ≤ 2), smooth turn off (positive and negative periods are equal for safe MLV transformer operation). Include transformer losses when calculating the load. Low end trim capability. |
|
|
|
Fluorescent: Electronic Fluorescent Dimming Ballast Special dimmers are designed and UL listed to send power and control signals to each type of electronic fluorescent dimming ballast.
|
|
|
Light Emitting Diode (LED): Electronic LED Driver Special dimmers are designed to send power and control signals to each type of electronic LED driver.
Special requirements | LED light source must be properly matched to LED driver, and LED driver must meet control specifications for control type (e.g. IEC for 0-10 V). |
|
|
Heat Dissipation During normal operation, dimmers get warm to the touch. Wallbox dimmer efficiency is typically around 99%. The other 1% is dissipated in the dimmer as heat. So, a 600 W load on a 600 W dimmer would produce around 6 watts of heat. This is approximately the heat generated from a small nightlight. Operating on its rated load, Lutron dimmers will stay below the UL limits of 140º F (60º C).
|
|
|
Ganging & Derating To help the dimmer dissipate the internal heat normal to operation, a typical dimmer is wider than a switch. Dimmers can be ganged together such that the space is the same as switches. A portion of the fins (heat sink) must be removed. The fins are grooved to make the removal of fins easy with a pair of pliers. The removal of fins reduces the wattage capacity (load) the dimmer can control.
|
|
|
Magnetic Low-voltage Dimmer Ratings The stated VA (volt-ampere) rating is the capacity of the dimmer that includes the magnetic transformer heat losses and the lamp load. A Lutron MLV dimmer UL listed for 1,000 VA can be loaded with a full 1,000 VA lamp load. A transformer dissipates up to 20% of the connected load as heat. Better transformers dissipate less than 10% as heat. Added together, the lamp load and the transformer loss determine the dimmer capacity required.
|
|
|
Electronic Low-voltage Dimmer Ratings Electronic low-voltage transformers also dissipate some heat. These inefficiencies are small enough to be accounted for in the dimmer rating. A Lutron ELV dimmer UL listed for 600 W can be loaded with a full 600 W lamp load. If ganged with other dimmers, standard derating rules apply.
|
|
|
|
|
|
|