I think someone asked this before but I couldn't find the answer. My new lights have the usual blk/wht power wires, along with red/blue bulb wiring and yellow which I believe is the common, However as the one yellow come from the ballast to the end sockets it changes to white. Where this ties, there is a plug type connector which appears to be able to be used to plug something into but it does not seem necessary for the function of this individual light fixture. What is this plug/pigtail for? This is a 8' 4-bulb T8 light.
I would show a diagram/drawing but I don't know how to do that. Can someone explain how to to that too?
Basically here is the wiring from the ballast: two red and two blue going to the respective middle sockets. One yellow going to the two sockets on one end, one yellow going to the other end but halfway there it changes to white in a little pigtail/plug. It seems you could plug something in here to tie on some other wiring, but I don't know why or what.
Thanks for the help.