Mitsubishi Electric MELSEC-Q/L Programming Manual page 207

Program example
■ADD, +
The program which performs addition ((s1) + (s2)) on double word (signed) type data input to (s1) and (s2), and outputs the
operation result from (d) in the same data type as that of (s1) and (s2).
[Structured ladder/FBD]
[ST]
g_dint3:=(g_dint1)+(g_dint2);
6 OPERATOR
205
6.1 Arithmetic Operations
6