Can I connect a single color LED string to a RGB DMX512 controller?
This was posted a long time ago but was never really answered.

But to answer; Yes! this will work just fine. The LED doesn't care what kind of signal it receives because all it wants is power. Which is exactly what your DMX RGB bridge provides. It literally "bridges" the digital DMX signal and converts it into an analog RGB signal. Technically, it converts it into just an analog power signal, but in this case, the bridge has the outputs marked RGB. Handy.