ABB ControlMaster CM10 - Page 84

ControlMaster CM10, CM30 and CM50
Universal process controllers,
1
/8,
1
/4 and
1
/2 DIN 7 Advanced Level
82 IM/CM/S–EN Rev. R
…Functions / …Math Blocks / …Block Type
Equation Enables an equation with up to 4 operands and 3 operators to be created. The operands can be
assigned to any analog or digital signal (see Appendix A, page 116). Digital signals have value of
either '0' or '1'. With the exception of the median operator, the equation is processed in a strict
left to right order, with no operator precedence.
The result of a math block can be used as the operand in another math block, enabling more
complex math equations to be constructed. The math blocks are processed in ascending order;
math block 1 is processed first, then math block 2, then 3 to 8:
Operand 1
Operand 2
Operand 3
Operand 4
Operator 1
Add, Subtract
Multiply, Divide
Low Select
High Select
Operator 2
Add, Subtract
Multiply, Divide
Low Select
High Select
Add, Subtract
Multiply, Divide
Low Select
High Select
Operator 3
Multiple Operand Math Block Equation