only 30 articles per time

I enter the correct data of remote servers and I begin the transfer process. I do check the option to fetch and images. The transfer begins normally but after transferring Articles 30 stops the transfer without errors.I have to I press stop of process and a starting again every 30 articles. I need to bring about a total of 36000 articles and he takes a long time. What must change;

P.S. Sorry for my poor englesh, i’m from Greece