Here's the answer

April 27, 2020   photos  

First of all, we can use three phase breaker of single phase breaker but it will not be good enough according to economically and technically three phase breaker four time expensive then the single phase. In addition to this, it is connected it in series connection by the meaning insert 1st phase in the 1st pole and take this phase from the 3rd pole. Finally, we can single or two phase in 3 phase circuit breaker in case of emergency, but its technically not good and much expensive. In general, it is not a good idea because it is too expensive! In the emergency, we can use make a loop from line 1 to line 2.