Another issue from my church's lighting. I am looking at moving some troffers and saw last thing yesterday that at least 1 pair of lights are primary/secondary (master/slave). I hadn't noticed any of them there before when changing ballasts all around, probably about 100. These are 2x4 with 3 lamps each. Church is considering dimmer ballasts for them. I have to check with supply house if they can be dimmed or if I should get a kit & convert the secondary to a primary. I never saw the value in this setup to begin with. Moving 1 will mean having to move the other, disconnect it or set a box in between with another whip.

I installed a few of these in the mid 90's & was under the impression they were on the way out then. But these would have been installed about 2004.

Anyone still installing these in your locations?