I am looking for a solution for some lighting that was installed recently. The lights are single LED downlights that are connected from a direct connection to 24Vdc through a constant current driver to the LED.
The problem is, there was supposed to be an emergency lighting supply connected to some of these lights as well, and there is a test button that will turn this supply on. This obviously would be problematic without some additional electronics that would allow the presence of the emergency supply to cut off the mains supply from an individual light (lights on a given circuit are not all fed with an emergency supply) and allow the emergency feed to take over, and of course, when the emergency feed is switched off, the mains would take over again.
I have been looking for a commercial product for such applications, but I have not yet come across any.
Does anyone know where I could look, or know how to do a DIY resolution with electronics?