- The show is about to start; the house lights dim; the audience becomes quiet as they look to the stage.
- Yesterday the ballroom was home to a bright and lively kitchen wares show; tomorrow it'll host an elegant fundraising fete. With the twist of a knob, the lighting is fine-tuned to suit any purpose.
- As the store closes for the evening, lights are left on for security. Although they'll burn through the night, they'll do so as energy-efficiently as possible: not only are they LED, they're dimmed to 30% when the last employee leaves the building.
- Office workers have task lights at their desks while the overhead lighting is maintained at less than full brightness, allowing employees to tailor their light levels to their individual needs while still maintaining the ability to brighten the entire room when required.
Dimming gives you control over the atmosphere of a space. It allows light to be moderated for the comfort and productivity of employees. It can be used to communicate. And it reduces energy usage and cost.
LED lighting with dimming-capable drivers can be paired with dimmer controllers to give you an impressive range of lighting control. Let's talk a bit about LED dimming technology and how to select a dimmer controller for your commercial, retail, or industrial application.
AC vs. 0-10V DC Dimming for LED Lighting
For dimmable LED lighting, 0-10V dimming, where the control signal is a DC voltage, is the best choice. Some LED products, such as the LED bulbs you buy at home improvement stores (and our own 4 foot dimmable LED tube), use AC dimming. AC dimming, however, limits the dimmable range of an LED bulb, and it can be hard on the AC bulb's AC to DC driver, due to the fact that the reduction of light is achieved by varying the AC voltage to the driver. When possible, you'll want to opt for a 0-10V capable LED bulb or fixture.
Once you've selected your dimmable LED lights, you'll need a dimmer controller to operate them. For commercial, retail, and industrial applications, you'll want to take special care in choosing that controller.
Dimmer Controllers & LED Lighting
A number of dimmer products on the market, such as the Lutron Diva/DVSTV, combine 0-10V dimming control with an on/off function. Seems sensible, right? Unfortunately, these controllers limit how many fixtures you can control with one switch. For residential, and even for small commercial applications, you would be fine, but when you need to operate higher-wattage lights, such as high bays in your warehouse, you'll quickly hit the controller's wattage limit. The aforementioned Diva, for instance, can only handle up to about 960W. Just five 200W LED high bays exceed that; you would need to split the lights over two separate controllers. The same goes for large banks of lower-wattage light: a grocery store running 8 foot LED tubes will hit its limit for a single combined controller at around 24 lights (fewer if you're using ultra-high-lumen or high output (HO) tubes).
For these applications, whether you're controlling a small group of high-wattage lights or a large area of lower-wattage lights, we recommend our customers install a 0-10V dimming knob alongside a separate on/off switch. While this will require a separate two-conductor DC wire run from the control switch to each of the lights, it will allow you control more lights simultaneously with a single interface. It's also a little cheaper than the combined controller.
Another limiting factor to consider is the distance wiring will run from the controller to the last driver. This should not exceed 300 feet when using 18 gauge wire or 400 feet with 16 gauge wire.
It's easier to do the wiring for this method when you're installing new LED fixtures; retrofitting existing lights to LED can make the needed wiring more of a challenge.
If you have any questions about dimmable LED lights and selecting the best dimmer controller for your needs, get in touch with us: