  We investigate current fluctuations in a three-terminal quantum dot in the
sequential tunneling regime. In the voltage-bias configuration chosen here, the
circuit is operated like a beam splitter, i.e. one lead is used as an input and
the other two as outputs. In the limit where a double occupancy of the dot is
not possible, a super-Poissonian Fano factor of the current in the input lead
and positive cross-correlations between the current fluctuations in the two
output leads can be obtained, due to dynamical channel-blockade. When a single
orbital of the dot transports current, this effect can be obtained by lifting
the spin-degeneracy of the circuit with ferromagnetic leads or with a magnetic
field. When several orbitals participate in the electronic conduction, lifting
spin-degeneracy is not necessary. In all cases, we show that a super-Poissonian
Fano factor for the input current is not equivalent to positive
cross-correlations between the outputs. We identify the conditions for
obtaining these two effects and discuss possible experimental realizations.
