How many hours should bot take a break?

[DiscoStu71]

I'm using one break (1 hour) to three hours farming - thinking that this will not 'trip' the personal timer set up in CoC.  So far, so good.  During the scheduled break(s), I rarely get raided, but when CF resumes, my personal timer is reset to 4 hours, and I continue farming until my next scheduled break, and repeat through the day/night.