Rievtech ELC-12AC-R-N, User Manual

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Parameter p (number of decimals)
The values V1, V2, V3, and V4 can be provided by the actual value of another already-programmed
function:
Analog comparator: Ax – Ay
Analog trigger: Ax
Analog amplifier: Ax
Analog multiplexer: AQ
Analog ramp: AQ
Analog math: AQ
PI controller: AQ
Data latching relay: AQ
Up/Down counter: Cnt
Parameter p applies to the display of V1, V2, V3, V4 and AQ in a message text.
Description of the function
The analog math function combines the four operands and three operators to form an equation. The
operator can be any one of the four standard operators: +, -, *, or /. For each operator, you must set a
unique priority of High ("H"), Medium ("M"), or Low ("L"). The high operation will be performed first,
followed by the medium operation, and then by the low operation. You must have exactly one operation
of each priority. The operand values can reference another previously-defined function to provide the
value. The analog math function rounds the result to the nearest integer value.
The number of operand values is fixed at four and the number of operators is fixed at 3. If you need to
use fewer operands, use constructions such as " + 0" or " * 1" to fill the remaining parameters.
You can also configure the behavior of the function when the Enable parameter "En"=0. The function
block can either retain its last value or be set to 0.
Possible errors: Zero division and overflow
If the analog math function block execution results in zero division or overflow, it sets internal bits that
indicate the type of error that occurred. You can program an analog math error detection function block
in your circuit program to detect these errors, and to control the program behavior as needed. You
program one analog math error detection function block to reference one specific analog math function
block.
Examples
The following tables show some simple example analog math block parameters, and the resulting
equations and output values:
V1 Operator1 V2 Operator2 V3 Operator3 V4
12 +(M) 6 /(H) 3 -(L) 1
Equation: (12 + (6 / 3)) - 1
Result: 13
V1 Operator1 V2 Operator2 V3 Operator3 V4