Function Blocks
2.37 MMA Function Block
Description
The MMA label stands for Min-Max-Average-Sum. This block is part of the Calculations category. It
looks like this graphically on the Control Builder.
Function
Accepts inputs from up to six analog input values (Xl - X6) and calculates these values for output:
• MIN - Minimum input value
• MAX - Maximum input value
• AVG - Average of the 6 input values
• SUM - Sum of the 6 input values
• DEV - Standard deviation of the 6 input values
• ALM - Alarm output for deviations
Turns ON ALM when any input is outside the configured number of standard deviations when the
configuration parameter DEV > 0.
• If DEV configured = 0, then:
•
If DEV configured 0, then:
102
– no standard deviation is calculated;
– all inputs connected to the block are used to calculate the MIN, MAX, AVG,
AND SUM outputs.
– the standard deviation is calculated for the number of inputs connected to the
block, and
– all inputs connected to the block are used to calculate the MIN, MAX, AVG,
.
and SUM outputs
Function Block Reference Guide
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