LEQ (Less Than or Equal To) Ladder Logic Instruction


The Less Than or Equal To instruction is a ladder logic rung input instruction that compares two values. If Source A is less than or equal to Source B the logic to the right of the instruction, or rung-condition-out, is enabled and disabled otherwise. The values can be constants, tags or any combination.

Strings can be compared. The software compares the hexadecimal value of the characters to determine if one string is greater than or less than another.

List of possible arguments

SOURCE A and SOURCE B can be any combination of the following data types.

  • SINT              
  • INT
  • DINT
  • REAL

Note: Negative numbers are valid.