I have 2 light switches that control all of our basement lights. Some of the lights are connected to one breaker and the rest of the basement lights are connected to another breaker. I want to install just one switch to turn on all of the basement lights at the same time. Currently, the 2 light switches are about 1/2 way down the basement stairs. I want to put just one light switch at the top of the stairs to control all of the basement lights. What I was thinking of doing was to remove the switches that are 1/2 way down the stairs, add another section of wire long enough to connect to the switch up to the top of the stairs and then connect the 3 white wires together, the 3 black wires together and the 3 ground wires together each with their own wing nut and then put a cover on the box and connect the switch to the long piece of wire at the top of the stairs? Will the fact that some of the lights are controlled by one circuit breaker and the rest of the lights are controlled by another circuit breaker make this impossible or cause any problems with the new circuit?

I've been searching, but haven't found a answer yet. About me: I'm not a electrician. But I know enough about how it works. I have previously rewired my old house upgrading a 60 amp fuse box to a 200 breaker box meter included. Then wired the entire house and passed the city inspection. My issue: Wife and I bought a house a little over a year ago. House was built in 1914. One of my requirements of moving was a 200 amp box, I lost that argument. This house was upgraded to a 100 amp box. House is a little over 3000 square feet. 100 is a bit small. But, everything worked and I figured I would upgrade eventually. I know it is needed. Fast do wear a year and I am beginning to work out in the garage some. It is powered by a single 20 amp breaker ran from the house. I ran my own gas line for heat in the garage and found the line. Direct burial NOT in conduit. I didn't disturb or break the line in any way. So garage is heated by a gas heater with a thermostat. 3 overhead lights, the T-8 style for now. Just replaced the garage door opener with a new 1.5 hp on one double door. There is also a exterior motion sensor light. Working in my garage I am using wood tool. Router 8 amp, planner 15 amp, table saw 15 amp. Only running one thing at a time. Suddenly the garage breaker starts tripping. Okay, I'm overloading it. Unplug all unnecessary whatevers. Trips. Not sure what to do, keep working, trips. Go inside to reset and somehow it has also tripped the main 100 amp breaker. Reset everything and clean up. Trips overnight. Only thing on would be the heater and possibly the sensor light. Trips today while at work. Heater is only thing on. Think maybe maybe a bad breaker. I replace with one I have left over from the last house. Go out to dinner with wife. All good. Come home park car in garage. All good. Let wife inside, walk back to garage...and tripped. Heater, garage opener, and sensor light on. Sorry for the long story, but wanted to give all the details. WITHOUT going out and replacing the meter and box tonight, what gives?!? I'm getting lost.