  By the method of discrete transformation equations of 3-th wave hierarchy are
constructed. The main difference compare with the systems connected with $A_1$
algebra consists in a fact that in $A_2$ case there are two different systems
of equations of the same degree (the maximal derivatives with respect to space
coordinate). In the present paper we construct only system of equations of
zero, first and second degree. At this moment the general method for solution
of this problem (the type of canonical Hamiltonian operators) is unknown for
the author and our direct calculationsare sufficiently combersome.
