Example:
DEFINE 1893 LOAD
ZONE 0.24 RF 5 I 1 SS 2 ST 1 DM 0.05 DT 1.5
LOAD 1:1893 LOAD X
LOAD 2:1893 LOAD Z
In the above command neither you have to define self-weight, member load, point load, floor load. than you will get an error when you do analysis.