I live in a town house. My main breaker is outside near the electric meter . The power goes from comed into meter to the main breaker then to my circuit box in my basement. I have never had problems now the main breaker has tripped and all power is shut down. No individual circuits trip. Comed says it is an internal problem. I have an electrcian coming in two days. Any ideas. Once the main is switched back on in about five hours it trips again. Only had on the TV and a couple lights.

Try with all inside circuit breakers off, if it still trips, it is either wiring shorted before it gets to the panel. An Amprobe would be handy to see what amount current if any at all is tripping it. Could be a defective Breaker