Sorry, that second part was just a ramble, I thought that space between would show that, my bad.
Nothing complicated at all really. I'm just wanting to make my footprint vertical instead of horizontal, aka "Shelve Lighting". With 4 COBs for example, 2 on top, the other two around 36" directly below them. With both box's(say 2'X2') being for veg it will be running the same exact time 18-6. One would be the mom's room and the other would be for the babies.
(@Larry3215 PWM dimming at the driver at the time of contact would just coddle the contacts. ramp down-ramp up measured in deciseconds. Any need of this would be based on thermal loads.
@Skybound Latching contact would most likely be in order, unless it's a CV. The average relay isn't really beefy enough for continuous duty, even if they state they are. Yes the math, that is the only "hard part". I could never imagine this application in this arena for doing this, any extra light would go to the wrong side...)
As for that part about splitting times... Who would even want to do that, I was only commenting on difficulty/complexity. It would be intermediate level at best, but again why, maybe ask @Larry3215? There could be a hidden answer but that's a whole different topic.