Sometimes I´ve got 2 TCP connections to Tor nodes (entry points), one is the 'main' that is used always when i run something through
Tor (iceweasel...) ,the other connection exchanges a few TCP packets every few minutes . 

The odd thing to me is that the second connection sometimes is established at the beginning when i start tor, sometimes it takes 10, 20 minutes later or
doesn´t establish the connection at all.

Does anyone know why is it for ? What kind of data is being transferred ?

pst: tor+proxychains