Options for integrating LEDs into an existing dimming system

Options for integrating LEDs into an existing dimming system

Posted by Tristan Hils, Stacy Knight on 1st Apr 2019

Non-Dim vs. Constant Module - what's the best way to integrate LEDs without replacing my dimming system?

Many facilities are making the switch to LED and are really happy with the results. LEDs are long-lasting, maintenance-free and energy-saving: that's a win-win-win! However, many of our customers have older systems where the existing dimming system is not LED compatible. The good news is that, in most cases, we can help your system work well with LEDs. Let's discuss:

1. Dimmers: Not all dimmable LEDs (LED fixtures or LED "lamps") will work with your existing dimming system! Many "dimmable" LEDs will NOT dim below a certain percentage and will flicker the lower they go on the dimming curve**. In addition, theatrical LED fixtures and intelligent lights should not be used with traditional dimmers and can end up with damage to their power supplies. So, do NOT rush out and buy dimmable LEDs or fixtures without understanding the ins-and-outs of how LEDs and dimmers work together.  We suggest doing a thorough test of one complete circuit on your dimming system if you are changing to dimmable LEDs. 

2. Non-Dims: Most existing dimmers can be programmed to be "non-dim." What does "non-dim" mean? Anything controlled by a "non-dim," circuit is no longer dimmable via the rack. In traditional dimming systems, fixtures are dimmed by a reduction of power by the dimmer. When a dimmer is switched to a non-dim, this functionality is lost. So a basic LED house light could turn on or off, but not be dimmed. However, any fixture that has DMX control and is meant to be dimmed can still be dimmed - but it is the fixture that is doing the dimming and not a dimmer. In terms of power, a "non-dim" unit (and the fixtures it controls) can still be turned on-or-off through communication with the rack. When the "non-dim" unit is off, there is no power flowing through that unit at all. The downside to "non-dims," is that some dimming systems may require a special handheld programmer or an old-fashioned DOS-based computer to change a dimmer to "non-dim." If you don't have these items on hand, you may need to hire a professional to make the switch. On other types of dimming systems, you can change the setting to "non-dim" directly on the dimmer or the control module.

3. Constant Modules: A "constant module" gets its name from the fact that it always has power "constantly" running through it (and subsequently to the fixtures that are connected to it). It cannot be turned on or off via communication with the rack. It can only be turned off by physically flipping the breaker on the constant module itself. Constant modules work well with LEDs and intelligent fixtures controlled via DMX where the dimming is done by the actual fixture. The constant module simply acts as a pass-through to the fixtures. The downside to constant modules is that they are always drawing and transmitting a small amount of power (which means you are losing some of the energy-saving benefits of LEDs). Constant modules must be purchased individually. They are specific to each dimming system manufacturer and model and are available for most systems.

So which will work best for you? This will depend on your ability to switch to non-dim and/or the availability and cost of constant modules for your system. In either case, using non-dims or constants is almost ALWAYS cheaper (and easier) than replacing your whole dimming system solely for the sake of LEDs. As always, please feel free to talk to your technician or call us toll-free at 866-457-5937 for more information.

**(The explanation of this phenomenon is spelled out in our blog "Why are my LED lights flickering?" Please check it out if you want all the technical details.)

Please note that the information above is a "basic overview" of non-dims and constants and that there are many nuances to these systems. Should you have questions or need additional information, please contact us toll-free at 1-866-457-5937.