Why arbiter is establishing connection with server even though I have specified it as "arbiter only" ?

I have replica set with one primary(x.x.x.3), one secondary (x.x.x.4)and one arbiter(x.x.x.5), where arbiter is there for only voting purpose. From tomcat I’m establishing connection with mongo which is primary at that time and I’m using haproxy to redirect the traffic to the mongo which is primary.
So, when primary goes down and secondary becomes primary, within this time tomcat is establishing some number of connection with arbiter but in tomcat no where i have mentioned about arbiter.
So, I have doubt like when there is voting are the connections are getting pointed to arbiter somehow?